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| author | EmacsConf <emacsconf-org@gnu.org> | 2025-12-07 09:41:21 -0500 |
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| committer | EmacsConf <emacsconf-org@gnu.org> | 2025-12-07 09:41:21 -0500 |
| commit | 3e82f47de59199ef75bdc98058a46dc2b04c624e (patch) | |
| tree | 3fd1a62404ff8b94439b1a1ff11a2ee79b03bbf8 | |
| parent | c00ea139adc08f36a717e9142f3a1440f759d6b7 (diff) | |
| download | emacsconf-wiki-3e82f47de59199ef75bdc98058a46dc2b04c624e.tar.xz emacsconf-wiki-3e82f47de59199ef75bdc98058a46dc2b04c624e.zip | |
Automated commit
| -rw-r--r-- | 2025/captions/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt | 2431 | ||||
| -rw-r--r-- | 2025/info/reader-after.md | 822 | ||||
| -rw-r--r-- | 2025/info/reader-before.md | 4 |
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diff --git a/2025/captions/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt b/2025/captions/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt new file mode 100644 index 00000000..7bd58b32 --- /dev/null +++ b/2025/captions/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt @@ -0,0 +1,2431 @@ +WEBVTT captioned by jay_bird and sachac + +NOTE An introduction to the Emacs reader + +00:00:00.720 --> 00:00:02.879 +Hello EmacsConf! + +00:00:02.880 --> 00:00:06.639 +Today I'm here to introduce you to the Emacs Reader. + +00:00:06.640 --> 00:00:08.759 +It is a general-purpose document viewer + +00:00:08.760 --> 00:00:12.319 +that lives inside our beloved Emacs. + +00:00:12.320 --> 00:00:14.159 +It tries to prioritize memory + +00:00:14.160 --> 00:00:17.159 +and performance efficiency as much as possible + +00:00:17.160 --> 00:00:20.519 +even when you're using a lower-end hardware. + +00:00:20.520 --> 00:00:22.119 +And, most importantly, + +00:00:22.120 --> 00:00:25.439 +it tries to do things in an Emacs manner. + +00:00:25.440 --> 00:00:26.999 +That is, it tries to integrate + +00:00:27.000 --> 00:00:29.719 +with existing packages as much as possible + +00:00:29.720 --> 00:00:32.239 +instead of reinventing the wheel. + +00:00:32.240 --> 00:00:36.119 +And architecturally, it tries to take the advantage + +00:00:36.120 --> 00:00:38.479 +of dynamic or native modules + +00:00:38.480 --> 00:00:44.759 +which were introduced back in 2015 into Emacs. + +NOTE Yet another document viewer in Emacs? + +00:00:44.760 --> 00:00:46.759 +You would ask, why exactly do we need + +00:00:46.760 --> 00:00:49.199 +another document viewer in Emacs? + +00:00:49.200 --> 00:00:51.839 +Don't we already have the built-in DocView + +00:00:51.840 --> 00:00:55.199 +and the notorious pdf-tools? + +00:00:55.200 --> 00:00:59.439 +Well, the built-in DocView has unusable latency, + +00:00:59.440 --> 00:01:01.399 +and I'm going to show you this later + +00:01:01.400 --> 00:01:04.599 +when I compare this with Emacs Reader. + +00:01:04.600 --> 00:01:08.079 +The famous pdf-tools has actually multiple issues. + +00:01:08.080 --> 00:01:10.639 +One, it is extremely memory-hungry + +00:01:10.640 --> 00:01:14.399 +regardless of what kind of PDFs you're reading. + +00:01:14.400 --> 00:01:17.939 +And, well, it can only read PDFs. + +00:01:17.940 --> 00:01:22.199 +Poppler, the library which pdf-tools uses, + +00:01:22.200 --> 00:01:23.879 +is actually sub-optimal, + +00:01:23.880 --> 00:01:25.799 +especially relative to MuPDF, + +00:01:25.800 --> 00:01:28.559 +which is what Emacs Reader is based on. + +00:01:28.560 --> 00:01:31.919 +pdf-tools is also extremely painful to install. + +00:01:31.920 --> 00:01:34.279 +If you've ever installed pdf-tools, + +00:01:34.280 --> 00:01:38.479 +you know that it has a bunch of dependencies, + +00:01:38.480 --> 00:01:42.319 +including a server that is supposedly packaged. + +00:01:42.320 --> 00:01:45.061 +across package managers, system package managers. + +00:01:45.062 --> 00:01:47.737 +It's extremely difficult to install + +00:01:47.738 --> 00:01:50.279 +and painful to install. + +00:01:50.280 --> 00:01:52.839 +And of course, pdf-tools + +00:01:52.840 --> 00:01:54.559 +since the last couple of years + +00:01:54.560 --> 00:01:56.559 +has not been maintained as much. + +00:01:56.560 --> 00:02:05.759 +There's huge PRs that have been unnoticed and unmerged. + +NOTE Architecture of Emacs Reader + +00:02:05.760 --> 00:02:08.999 +Architecturally, Emacs Reader takes a distance + +00:02:09.000 --> 00:02:12.559 +from both DocView and pdf-tools. + +00:02:12.560 --> 00:02:15.399 +So how DocView works is that + +00:02:15.400 --> 00:02:18.679 +it basically wraps around + +00:02:18.680 --> 00:02:20.879 +a tool called mutool. + +00:02:20.880 --> 00:02:22.319 +mutool is actually + +00:02:22.320 --> 00:02:26.119 +a command line tool from MuPDF itself. + +00:02:26.120 --> 00:02:28.199 +It relies on mutool and a bunch + +00:02:28.200 --> 00:02:30.579 +of other similar command line tools, + +00:02:30.580 --> 00:02:34.199 +and basically makes process calls + +00:02:34.200 --> 00:02:36.519 +from Elisp to the CLI tools. + +00:02:36.520 --> 00:02:38.639 +That's how DocView works, + +00:02:38.640 --> 00:02:41.319 +and that's why it sort of has latency issues + +00:02:41.320 --> 00:02:42.519 +because that's the best you can do + +00:02:42.520 --> 00:02:45.019 +by literally calling CLI tools + +00:02:45.020 --> 00:02:50.679 +and outputting the images into Emacs. + +00:02:50.680 --> 00:02:55.039 +How pdf-tools works is that it tries + +00:02:55.040 --> 00:02:57.479 +to have a server-client model. + +00:02:57.480 --> 00:02:58.999 +So the client is Emacs + +00:02:59.000 --> 00:03:00.559 +and the server is basically + +00:03:00.560 --> 00:03:02.999 +something they call epdfinfo. + +00:03:03.000 --> 00:03:07.240 +It's supposed to render the images using Poppler + +00:03:07.241 --> 00:03:10.919 +and then send the images to Emacs + +00:03:10.920 --> 00:03:13.279 +which then tries to display. + +00:03:13.280 --> 00:03:16.279 +I think the server client model is terrible. + +00:03:16.280 --> 00:03:18.079 +One, for latency purposes, + +00:03:18.080 --> 00:03:19.839 +and two, it makes things + +00:03:19.840 --> 00:03:21.799 +unnecessarily more complicated. + +00:03:21.800 --> 00:03:24.199 +Here is where we come + +00:03:24.200 --> 00:03:26.679 +and introduce dynamic modules. + +00:03:26.680 --> 00:03:30.579 +So Emacs Reader is based on + +00:03:30.580 --> 00:03:32.279 +the concept of dynamic modules + +00:03:32.280 --> 00:03:34.279 +which I'm going to talk about in a bit. + +00:03:34.280 --> 00:03:37.159 +But how it works is that we have C modules. + +00:03:37.160 --> 00:03:39.039 +So we have the emacs-module.h, + +00:03:39.040 --> 00:03:40.679 +that's the dynamic module header + +00:03:40.680 --> 00:03:43.159 +which every dynamic module package must have. + +00:03:43.160 --> 00:03:45.479 +And then we have our C files. + +00:03:45.480 --> 00:03:52.579 +And these C files essentially define functions + +00:03:52.580 --> 00:03:56.439 +that are going to be used in Emacs but in C. + +00:03:56.440 --> 00:03:59.319 +We then load these C modules + +00:03:59.320 --> 00:04:03.799 +using simple (require ...) in our Elisp modules. + +00:04:03.800 --> 00:04:05.079 +And then whenever we call + +00:04:05.080 --> 00:04:07.119 +something in the Emacs runtime, + +00:04:07.120 --> 00:04:09.159 +say I'm going to open + +00:04:09.160 --> 00:04:13.559 +PDF files in (find-file) or (reader-open-doc), + +00:04:13.560 --> 00:04:15.799 +what it does is that + +00:04:15.800 --> 00:04:19.039 +it tries to use one of the functions + +00:04:19.040 --> 00:04:20.999 +that is wrapped in Elisp, + +00:04:21.000 --> 00:04:24.839 +but actually tries to call a function in C. + +00:04:24.840 --> 00:04:26.839 +And then the C module is actually + +00:04:26.840 --> 00:04:29.279 +going to make calls to the MuPDF. + +00:04:29.280 --> 00:04:31.599 +Here the MuPDF system package, + +00:04:31.600 --> 00:04:33.399 +this is actually a system package + +00:04:33.400 --> 00:04:35.839 +that is dynamically linked to the C modules. + +00:04:35.840 --> 00:04:36.919 +So we're basically + +00:04:36.920 --> 00:04:39.799 +just using it as a shared library. + +00:04:39.800 --> 00:04:43.359 +So you have the fz_load_page, for example, + +00:04:43.360 --> 00:04:44.839 +it's a MuPDF function + +00:04:44.840 --> 00:04:47.399 +that we're going to be using in the C modules. + +00:04:47.400 --> 00:04:50.079 +So it's going to make + +00:04:50.080 --> 00:04:53.279 +a shared dynamic call to MuPDF + +00:04:53.280 --> 00:04:55.119 +and then render the page + +00:04:55.120 --> 00:04:59.179 +and then show this to Emacs. + +00:04:59.180 --> 00:05:01.839 +This pipeline, I argue, + +00:05:01.840 --> 00:05:05.599 +is much better and leaner and efficient + +00:05:05.600 --> 00:05:07.639 +than a server-client model. + +00:05:07.640 --> 00:05:09.479 +One, because we don't really need + +00:05:09.480 --> 00:05:10.839 +the server-client model. + +00:05:10.840 --> 00:05:12.359 +So back when Politza + +00:05:12.360 --> 00:05:14.759 +first introduced pdf-tools, + +00:05:14.760 --> 00:05:19.759 +that was like 10 years ago in 2015, + +00:05:19.760 --> 00:05:21.240 +the concept of dynamic modules + +00:05:21.241 --> 00:05:23.279 +were not integrated into Emacs. + +00:05:23.280 --> 00:05:24.359 +I think they came around + +00:05:24.360 --> 00:05:28.079 +like one or two years late, 2017. + +00:05:28.080 --> 00:05:31.219 +So that's the best he could go with. + +00:05:31.220 --> 00:05:33.079 +We don't really have to, today, + +00:05:33.080 --> 00:05:35.719 +because, since we can use MuPDF + +00:05:35.720 --> 00:05:36.999 +as a shared library + +00:05:37.000 --> 00:05:39.479 +which can render things in real-time + +00:05:39.480 --> 00:05:41.759 +and just give us the rendered images + +00:05:41.760 --> 00:05:43.599 +which we can then display, + +00:05:43.600 --> 00:05:49.659 +there's no reason for a server to do things for us. + +00:05:49.660 --> 00:05:53.359 +So that's the main architectural difference + +00:05:53.360 --> 00:05:55.479 +that Emacs Reader introduces + +00:05:55.480 --> 00:06:00.279 +compared to pdf-tools and DocView. + +NOTE A word on dynamic modules + +00:06:00.280 --> 00:06:02.479 +What exactly are dynamic modules? + +00:06:02.480 --> 00:06:04.119 +Well, I can't really give you + +00:06:04.120 --> 00:06:06.199 +a full-fledged explanation, + +00:06:06.200 --> 00:06:08.639 +but essentially dynamic modules + +00:06:08.640 --> 00:06:10.519 +let you evaluate + +00:06:10.520 --> 00:06:12.039 +native compiled code + +00:06:12.040 --> 00:06:15.119 +in other languages like C, C++, Rust + +00:06:15.120 --> 00:06:18.519 +that behaves like regular Emacs Lisp. + +00:06:18.520 --> 00:06:23.639 +So when our Emacs C modules, + +00:06:23.640 --> 00:06:26.039 +the render-core.c or render-theme.c, + +00:06:26.040 --> 00:06:28.299 +when all of these are compiled, + +00:06:28.300 --> 00:06:30.839 +and they're called from the Elisp modules. + +00:06:30.840 --> 00:06:34.439 +They behave like Elisp even though + +00:06:34.440 --> 00:06:37.039 +they're as fast as a C function + +00:06:37.040 --> 00:06:39.359 +because they're compiled C code. + +00:06:39.360 --> 00:06:41.399 +But you essentially call them + +00:06:41.400 --> 00:06:42.759 +just like Elisp functions. + +00:06:42.760 --> 00:06:47.819 +You can find them using C-h f and so on. + +00:06:47.820 --> 00:06:49.679 +So you can call any function + +00:06:49.680 --> 00:06:51.719 +from any language that supports + +00:06:51.720 --> 00:06:53.519 +the C ABI, which is virtually everything, + +00:06:53.520 --> 00:06:54.919 +without leaving Emacs + +00:06:54.920 --> 00:06:56.759 +and without losing any performance. + +00:06:56.760 --> 00:06:58.479 +This is extremely helpful + +00:06:58.480 --> 00:06:59.919 +when you want to use + +00:06:59.920 --> 00:07:02.119 +existing libraries like MuPDF + +00:07:02.120 --> 00:07:04.079 +or any other cryptographic library + +00:07:04.080 --> 00:07:06.039 +that is written in C + +00:07:06.040 --> 00:07:07.037 +and you don't want to rewrite + +00:07:07.038 --> 00:07:08.537 +the entire thing in Elisp, + +00:07:08.538 --> 00:07:11.739 +but you can just use it as a native library. + +00:07:11.740 --> 00:07:13.039 +You can read more + +00:07:13.040 --> 00:07:14.679 +on how dynamic modules work + +00:07:14.680 --> 00:07:17.759 +and how you can write one in this blog. + +00:07:17.760 --> 00:07:19.479 +This is something that I wrote myself + +00:07:19.480 --> 00:07:22.239 +just after starting this package + +00:07:22.240 --> 00:07:25.439 +and it will give you a bit more guidance + +00:07:25.440 --> 00:07:27.519 +on how to use dynamic modules more efficiently. + +00:07:27.520 --> 00:07:28.679 +I think dynamic modules + +00:07:28.680 --> 00:07:32.299 +should be used more and more in Emacs + +00:07:32.300 --> 00:07:34.519 +and I think their advantages + +00:07:34.520 --> 00:07:36.079 +have not been exploited + +00:07:36.080 --> 00:07:39.559 +as much as they should. + +NOTE Features of Emacs Reader + +00:07:39.560 --> 00:07:42.319 +Now we're going to talk a bit about + +00:07:42.320 --> 00:07:46.719 +the core features of Emacs Reader. + +00:07:46.720 --> 00:07:48.879 +And these are the following features + +00:07:48.880 --> 00:07:50.399 +that we're going to talk about. + +00:07:50.400 --> 00:07:51.959 +And finally, to talk about + +00:07:51.960 --> 00:07:56.759 +some challenges that we faced. + +NOTE Memory efficiency + +00:07:56.760 --> 00:07:58.519 +First is memory efficiency. + +00:07:58.520 --> 00:08:00.819 +I already told you that + +00:08:00.820 --> 00:08:03.239 +Emacs Reader's first priority + +00:08:03.240 --> 00:08:06.439 +is to make sure that we are not slow + +00:08:06.440 --> 00:08:07.959 +and we are not taking + +00:08:07.960 --> 00:08:10.319 +a bunch of memory unnecessarily. + +00:08:10.320 --> 00:08:14.439 +So here's a graph of the heap memory size + +00:08:14.440 --> 00:08:17.919 +as it grows for DocView. + +00:08:17.920 --> 00:08:20.637 +So this is again in emacs -Q. + +00:08:20.638 --> 00:08:22.399 +So this is a fresh Emacs session + +00:08:22.400 --> 00:08:25.279 +with just DocView. + +00:08:25.280 --> 00:08:27.819 +It grows up to 900MB + +00:08:27.820 --> 00:08:31.559 +for a very small PDF that is a LaTeX PDF. + +00:08:31.560 --> 00:08:36.779 +No scanned huge PDF. It's a 2MB PDF. + +00:08:36.780 --> 00:08:39.679 +But when I scrolled from the beginning + +00:08:39.680 --> 00:08:41.619 +of the PDF to the end, + +00:08:41.620 --> 00:08:43.639 +it went up to 900MB. + +00:08:43.640 --> 00:08:46.819 +That's the memory heap size. + +00:08:46.820 --> 00:08:49.699 +Does pdf-tools make this any better? + +00:08:49.700 --> 00:08:51.919 +It actually doesn't. + +00:08:51.920 --> 00:08:55.039 +So, pdf-tools pretty much + +00:08:55.040 --> 00:08:57.219 +does the same thing. + +00:08:57.220 --> 00:08:58.439 +if you look at it here + +00:08:58.440 --> 00:09:01.359 +just so if you're going to ask me + +00:09:01.360 --> 00:09:02.939 +are they two different graphs, + +00:09:02.940 --> 00:09:04.839 +or are you just showing me the same graph, + +00:09:04.840 --> 00:09:06.119 +they're actually two different graphs, + +00:09:06.120 --> 00:09:08.779 +because if you look at the DocView graph + +00:09:08.780 --> 00:09:11.559 +it uses cairo and it uses librsvg + +00:09:11.560 --> 00:09:13.439 +because docview by default + +00:09:13.440 --> 00:09:16.119 +converts the images into SVG. + +00:09:16.120 --> 00:09:17.999 +The rendered images are SVGs. + +00:09:18.000 --> 00:09:20.559 +pdf-tools doesn't, so you don't see + +00:09:20.560 --> 00:09:24.039 +any librsvg calls here or anything + +00:09:24.040 --> 00:09:25.439 +So this is pdf-tools + +00:09:25.440 --> 00:09:27.079 +and it basically takes up + +00:09:27.080 --> 00:09:29.079 +the same amount of memory, 900MB, + +00:09:29.080 --> 00:09:30.919 +and exactly the same operation, + +00:09:30.920 --> 00:09:32.479 +exactly the same PDF, + +00:09:32.480 --> 00:09:36.139 +exactly scrolling from first to the last. + +00:09:36.140 --> 00:09:37.719 +Where do we stand? + +00:09:37.720 --> 00:09:40.559 +Well, we actually do much better. + +00:09:40.560 --> 00:09:42.599 +So let me zoom in this. + +00:09:42.600 --> 00:09:46.319 +So if you see, we stand within + +00:09:46.320 --> 00:09:49.259 +at a peak of 72MB. + +00:09:49.260 --> 00:09:51.279 +Exactly the same PDF, + +00:09:51.280 --> 00:09:53.039 +exactly the same operation + +00:09:53.040 --> 00:09:54.559 +from the beginning to the end, + +00:09:54.560 --> 00:09:57.599 +around 285 pages scrolled. + +00:09:57.600 --> 00:10:03.239 +We take much less than 80 MB. + +00:10:03.240 --> 00:10:05.071 +And actually, to be very frank, + +00:10:05.072 --> 00:10:09.204 +the only memory that we're storing in Emacs, + +00:10:09.205 --> 00:10:12.439 +oh, sorry, not in Emacs, + +00:10:12.440 --> 00:10:16.599 +in the MuPDF heap is just about 30 MB. + +00:10:16.600 --> 00:10:19.119 +It's this dark red one. + +00:10:19.120 --> 00:10:22.559 +That's the cache that we're storing. + +00:10:22.560 --> 00:10:24.759 +That's the memory that we're interacting with + +00:10:24.760 --> 00:10:25.479 +in real time. + +00:10:25.480 --> 00:10:29.199 +This is stuff that Emacs adds on top of it + +00:10:29.200 --> 00:10:32.919 +and a bit of libmupdf. + +00:10:32.920 --> 00:10:35.199 +So you can see, in terms of memory, + +00:10:35.200 --> 00:10:37.239 +we're saving... + +00:10:37.240 --> 00:10:41.119 +we're literally down, + +00:10:41.120 --> 00:10:45.359 +what, a fraction of 10! + +00:10:45.360 --> 00:10:48.519 +This was a priority for us + +00:10:48.520 --> 00:10:49.279 +since the beginning, + +00:10:49.280 --> 00:10:51.999 +because when I was starting to use pdf-tools, + +00:10:52.000 --> 00:10:53.359 +it was unusable for me + +00:10:53.360 --> 00:10:55.159 +because I was on a lower-end hardware + +00:10:55.160 --> 00:10:57.599 +and I thought it should not be + +00:10:57.600 --> 00:10:58.959 +really that difficult + +00:10:58.960 --> 00:11:00.879 +for a document reader + +00:11:00.880 --> 00:11:04.099 +to not take a gigabyte of memory. + +00:11:04.100 --> 00:11:05.919 +It really shouldn't because + +00:11:05.920 --> 00:11:07.359 +you're not really doing that much, + +00:11:07.360 --> 00:11:10.919 +you're just displaying images. + +00:11:10.920 --> 00:11:12.239 +So that's how efficient + +00:11:12.240 --> 00:11:13.639 +we are in terms of memory. + +00:11:13.640 --> 00:11:15.371 +Let's see how efficient + +00:11:15.372 --> 00:11:18.719 +we are in terms of speed. + +NOTE Performance and speed + +00:11:18.720 --> 00:11:21.099 +So Emacs Reader is actually + +00:11:21.100 --> 00:11:23.119 +as fast as pdf-tools, + +00:11:23.120 --> 00:11:24.079 +and it is actually + +00:11:24.080 --> 00:11:27.239 +way more faster than DocView. + +00:11:27.240 --> 00:11:28.559 +In some cases, + +00:11:28.560 --> 00:11:31.679 +it actually beats existing + +00:11:31.680 --> 00:11:34.859 +standalone document readers and browsers. + +00:11:34.860 --> 00:11:41.119 +So let's actually see this in action. + +00:11:41.120 --> 00:11:42.319 +So here we are with + +00:11:42.320 --> 00:11:46.039 +a few emacs -Q sessions. + +00:11:46.040 --> 00:11:50.719 +I'm using emacs -Q so as to give you... + +00:11:50.720 --> 00:11:52.159 +that this is actually + +00:11:52.160 --> 00:11:55.139 +as less overhead possible. + +00:11:55.140 --> 00:11:57.359 +So we have first DocView. + +00:11:57.360 --> 00:12:01.137 +All of these tests + +00:12:01.138 --> 00:12:03.039 +are going to be done on the same PDF. + +00:12:03.040 --> 00:12:07.199 +It's the documentation manual from MuPDF. + +00:12:07.200 --> 00:12:10.559 +So if I scroll, this is fine. + +00:12:10.560 --> 00:12:12.859 +I'm just pressing n + +00:12:12.860 --> 00:12:15.159 +and it seems to work fine. + +00:12:15.160 --> 00:12:19.519 +If I press and hold n, + +00:12:19.520 --> 00:12:21.799 +I have pressed n and I'm holding. + +00:12:21.800 --> 00:12:26.419 +And Emacs is stuck. + +00:12:26.420 --> 00:12:27.559 +And it's going to stay stuck + +00:12:27.560 --> 00:12:28.799 +because it's making calls + +00:12:28.800 --> 00:12:31.279 +to the CLI tool that I said, mutool. + +00:12:31.280 --> 00:12:35.519 +And after it's done getting stuck, + +00:12:35.520 --> 00:12:40.179 +it is going to get back. + +00:12:40.180 --> 00:12:43.039 +As you can see, if you go back, + +00:12:43.040 --> 00:12:45.079 +you're able to go back fine. + +00:12:45.080 --> 00:12:46.199 +It does not get stuck + +00:12:46.200 --> 00:12:48.439 +because what Emacs does + +00:12:48.440 --> 00:12:51.519 +is it basically calls mutool, + +00:12:51.520 --> 00:12:53.239 +like fetches a bunch of pages, + +00:12:53.240 --> 00:12:54.919 +essentially all the pages + +00:12:54.920 --> 00:12:56.199 +that you asked for it, + +00:12:56.200 --> 00:12:59.159 +and it puts them into the memory. + +00:12:59.160 --> 00:12:59.879 +And that's it. + +00:12:59.880 --> 00:13:01.199 +It puts them into the memory + +00:13:01.200 --> 00:13:03.139 +and then scrolls through it. + +00:13:03.140 --> 00:13:05.839 +So going back, you will most likely + +00:13:05.840 --> 00:13:07.239 +not have any stuck issues. + +00:13:07.240 --> 00:13:07.839 +Sometimes you do + +00:13:07.840 --> 00:13:10.919 +because some images do get GC'd. + +00:13:10.920 --> 00:13:13.599 +But that's the idea. + +00:13:13.600 --> 00:13:16.639 +Whenever there's no image in memory, + +00:13:16.640 --> 00:13:18.739 +it gets stuck. + +00:13:18.740 --> 00:13:21.239 +And it gets stuck good. + +00:13:21.240 --> 00:13:23.579 +That's DocView. + +00:13:23.580 --> 00:13:25.199 +pdf-tools is actually + +00:13:25.200 --> 00:13:27.359 +not problematic here. + +00:13:27.360 --> 00:13:29.039 +pdf-tools is extremely efficient + +00:13:29.040 --> 00:13:30.199 +and extremely fast. + +00:13:30.200 --> 00:13:32.839 +So we can go through the pages + +00:13:32.840 --> 00:13:34.479 +without any issues. + +00:13:34.480 --> 00:13:37.159 +We can zoom. + +00:13:37.160 --> 00:13:39.879 +The zoom did get stuck a bit, + +00:13:39.880 --> 00:13:44.039 +but that's relatively fine. + +00:13:44.040 --> 00:13:46.959 +Emacs Reader is exactly as fast + +00:13:46.960 --> 00:13:49.199 +as pdf-tools here. + +00:13:49.200 --> 00:13:50.279 +So this is pdf-view, + +00:13:50.280 --> 00:13:51.279 +this is Emacs Reader. + +00:13:51.860 --> 00:13:55.759 +Let's scroll through the pages. + +00:13:55.760 --> 00:13:59.159 +As you can see, nothing is getting stuck + +00:13:59.160 --> 00:14:00.919 +because we're not really waiting + +00:14:00.920 --> 00:14:06.359 +for any tool to send us any images. + +00:14:06.360 --> 00:14:08.299 +We just have a little cache + +00:14:08.300 --> 00:14:09.399 +and we're scrolling through them + +00:14:09.400 --> 00:14:13.959 +and rendering images in real time. + +00:14:13.960 --> 00:14:17.279 +Zooming also works fine. + +00:14:17.280 --> 00:14:19.519 +So, with regards to this, + +00:14:19.520 --> 00:14:23.679 +we're in parity with pdf-tools. + +NOTE Scanned PDFs + +00:14:23.680 --> 00:14:26.319 +Now, where pdf-tools and actually + +00:14:26.320 --> 00:14:28.079 +a lot of readers have issues + +00:14:28.080 --> 00:14:32.499 +is when they're dealing with scanned PDF. + +00:14:32.500 --> 00:14:36.839 +So, we have this PDF which is notorious + +00:14:36.840 --> 00:14:40.599 +for being really difficult to render + +00:14:40.600 --> 00:14:42.599 +because this is entirely built + +00:14:42.600 --> 00:14:43.479 +with scanned images. + +00:14:43.480 --> 00:14:44.619 +This is the kind of PDF + +00:14:44.620 --> 00:14:46.519 +that you get from Internet Archive. + +00:14:46.520 --> 00:14:47.839 +This is essentially someone + +00:14:47.840 --> 00:14:50.919 +took photos of the book in a camera + +00:14:50.920 --> 00:14:56.659 +and literally turned them into a PDF. + +00:14:56.660 --> 00:14:58.719 +Emacs Reader actually does not have + +00:14:58.720 --> 00:15:01.079 +any issues rendering this. + +00:15:01.080 --> 00:15:05.119 +As you can see, it renders it smoothly + +00:15:05.120 --> 00:15:09.679 +and fine without any halts. + +00:15:09.680 --> 00:15:13.959 +I can change Emacs even while it's doing so, + +00:15:13.960 --> 00:15:17.139 +and it does not have any issues. + +00:15:17.140 --> 00:15:20.071 +pdf-tools are the same. + +00:15:20.072 --> 00:15:21.759 +PDF also does not have any issues. + +00:15:21.760 --> 00:15:26.579 +Sorry. Click pdf-view-mode. + +00:15:26.580 --> 00:15:29.859 +pdf-view (pdf-tools) is a bit slower + +00:15:29.860 --> 00:15:35.619 +but does not have any issues. It works. + +00:15:35.620 --> 00:15:40.700 +Here, actually, pdf-tools and Emacs Reader + +00:15:40.701 --> 00:15:46.099 +are more efficient than even browsers. + +00:15:46.100 --> 00:15:47.199 +So, if I try to open + +00:15:47.200 --> 00:15:50.839 +the same page in a browser, + +00:15:50.840 --> 00:15:52.919 +I'm trying to scroll. + +00:15:52.920 --> 00:15:54.919 +And after I've scrolled and I leave, + +00:15:54.920 --> 00:15:58.119 +scrolling is going to load + +00:15:58.120 --> 00:15:59.839 +for a bunch of seconds + +00:15:59.840 --> 00:16:03.139 +to give me the page. + +00:16:03.140 --> 00:16:04.679 +It's more than five seconds, + +00:16:04.680 --> 00:16:05.479 +as you can see, + +00:16:05.480 --> 00:16:08.639 +and this is actually totally not usable. + +00:16:08.640 --> 00:16:10.199 +If you're going to read this book, + +00:16:10.200 --> 00:16:11.999 +an electromagnetics book, + +00:16:12.000 --> 00:16:13.599 +you're going to have a terrible time + +00:16:13.600 --> 00:16:14.759 +reading this in a browser, + +00:16:14.760 --> 00:16:15.479 +which is supposed to be + +00:16:15.480 --> 00:16:17.159 +the fastest thing alive. + +00:16:17.160 --> 00:16:19.119 +You sort of have the same experience + +00:16:19.120 --> 00:16:20.559 +in Okular. So this is Okular. + +00:16:20.560 --> 00:16:22.439 +If I try to scroll through this, + +00:16:22.440 --> 00:16:25.419 +it will do the same thing. + +00:16:25.420 --> 00:16:28.519 +And while it is better than the browser, + +00:16:28.520 --> 00:16:31.119 +it still takes a while + +00:16:31.120 --> 00:16:34.119 +and it still has, like, if you zoom, + +00:16:34.120 --> 00:16:36.799 +you're going to have a bit of a delay. + +00:16:36.800 --> 00:16:41.579 +You don't really face that in Emacs Reader. + +00:16:41.580 --> 00:16:45.259 +We zoom in and out just fine. + +00:16:45.260 --> 00:16:47.239 +And even with using mouse, + +00:16:47.240 --> 00:16:51.839 +you can zoom in and out just fine. + +00:16:51.840 --> 00:16:54.799 +So this is how Emacs Reader performs + +00:16:54.800 --> 00:17:01.119 +in terms of speed with these other tools. + +00:17:01.120 --> 00:17:08.959 +Now we will go back to the original presentation. + +NOTE System-level multi-threading + +00:17:08.960 --> 00:17:11.919 +Now, how exactly is Emacs Reader + +00:17:11.920 --> 00:17:14.079 +able to do a lot of this? + +00:17:14.080 --> 00:17:17.839 +I wish I could sort of spend + +00:17:17.840 --> 00:17:18.999 +an entire session + +00:17:19.000 --> 00:17:21.239 +just talking about this, but I can't. + +00:17:21.240 --> 00:17:22.919 +So I'm just going to make this short. + +00:17:22.920 --> 00:17:24.799 +When you load Emacs Reader, + +00:17:24.800 --> 00:17:26.319 +in the standard output, + +00:17:26.320 --> 00:17:27.439 +it's going to say this: + +00:17:27.440 --> 00:17:29.279 +that eight threads have been initialized. + +00:17:29.280 --> 00:17:32.679 +Now, what we did with Emacs here + +00:17:32.680 --> 00:17:33.799 +is that we enabled + +00:17:33.800 --> 00:17:35.039 +system-level multithreading. + +00:17:35.040 --> 00:17:36.639 +Now, Emacs is not multithreaded. + +00:17:36.640 --> 00:17:38.199 +We all know that notoriously. + +00:17:38.200 --> 00:17:39.519 +It is single-threaded. + +00:17:39.520 --> 00:17:41.479 +But we don't really + +00:17:41.480 --> 00:17:43.819 +need Emacs to be multithreaded, though. + +00:17:43.820 --> 00:17:45.759 +Emacs does not need to be multithreaded. + +00:17:45.760 --> 00:17:47.199 +What needs to be multithreaded + +00:17:47.200 --> 00:17:48.519 +is the rendering part + +00:17:48.520 --> 00:17:50.759 +because that's the most expensive part. + +00:17:50.760 --> 00:17:53.519 +In Emacs, we're only just displaying images. + +00:17:53.520 --> 00:17:56.479 +Emacs itself does not have a PDF engine + +00:17:56.480 --> 00:17:57.919 +that is rendering stuff. + +00:17:57.920 --> 00:18:00.559 +MuPDF is supposed to take care of that. + +00:18:00.560 --> 00:18:03.199 +So if I can do multithreading + +00:18:03.200 --> 00:18:05.079 +in the rendering pipeline, + +00:18:05.080 --> 00:18:07.119 +that is when I'm rendering pages + +00:18:07.120 --> 00:18:08.719 +instead of displaying them, + +00:18:08.720 --> 00:18:10.279 +that's fine for me because + +00:18:10.280 --> 00:18:11.679 +the rendering part most of the time, + +00:18:11.680 --> 00:18:12.959 +especially in scanned PDFs, + +00:18:12.960 --> 00:18:14.679 +is the most expensive part. + +00:18:14.680 --> 00:18:16.439 +So if you look at this graph, + +00:18:16.440 --> 00:18:17.959 +we have two parts here. + +00:18:17.960 --> 00:18:19.679 +We have the display pipeline + +00:18:19.680 --> 00:18:22.279 +and we have the rendering pipeline. + +00:18:22.280 --> 00:18:23.639 +In the display pipeline, + +00:18:23.640 --> 00:18:26.519 +we have just the Emacs session + +00:18:26.520 --> 00:18:29.359 +which has the reader loaded + +00:18:29.360 --> 00:18:31.579 +and that's the main thread. + +00:18:31.580 --> 00:18:33.319 +Then we have the rendering pipeline + +00:18:33.320 --> 00:18:35.559 +which has the MuPDF system package + +00:18:35.560 --> 00:18:38.459 +dynamically linked. + +00:18:38.460 --> 00:18:40.399 +So when you load Emacs Reader, + +00:18:40.400 --> 00:18:45.159 +we initialize a thread pool with eight threads. + +00:18:45.160 --> 00:18:48.759 +Now what you do is let's say we are at page 50. + +00:18:48.760 --> 00:18:51.759 +At page 50, the Emacs Reader + +00:18:51.760 --> 00:18:53.999 +maintains a cache. + +00:18:54.000 --> 00:18:56.519 +It's like a stack of pages + +00:18:56.520 --> 00:18:58.479 +that we keep in memory all the time. + +00:18:58.480 --> 00:19:02.519 +This cache is entirely outside of Emacs. + +00:19:02.520 --> 00:19:04.559 +It is not inside Emacs environment. + +00:19:04.560 --> 00:19:07.570 +It is in the C memory heap, + +00:19:07.571 --> 00:19:09.119 +in the MuPDF memory heap + +00:19:09.120 --> 00:19:11.119 +that is outside of Emacs environment. + +00:19:11.120 --> 00:19:13.839 +It does not make any calls to Emacs anything. + +00:19:13.840 --> 00:19:15.799 +It does not have a single Elisp line. + +00:19:15.800 --> 00:19:20.119 +So this cache is stored outside. + +00:19:20.120 --> 00:19:22.079 +Now when I want to retrieve + +00:19:22.080 --> 00:19:23.439 +anything from this cache, + +00:19:23.440 --> 00:19:26.199 +let's say, so I have cached + +00:19:26.200 --> 00:19:29.359 +up until 55, from 45 to 55. + +00:19:29.360 --> 00:19:31.079 +So what happens is that + +00:19:31.080 --> 00:19:32.759 +when you're at page 50, + +00:19:32.760 --> 00:19:34.359 +you always have a cache + +00:19:34.360 --> 00:19:36.719 +that's n + 5 and n - 5. + +00:19:36.720 --> 00:19:39.719 +So you have cache of 5 pages forward + +00:19:39.720 --> 00:19:41.959 +and 5 pages backward. + +00:19:41.960 --> 00:19:44.399 +But let's say I want to go to page 56. + +00:19:45.140 --> 00:19:50.079 +So I will ask an Emacs render page 56. + +00:19:50.080 --> 00:19:51.399 +And I'm not going to ask it + +00:19:51.400 --> 00:19:53.079 +to MuPDF directly. + +00:19:53.080 --> 00:19:54.399 +I'm going to ask it + +00:19:54.400 --> 00:19:56.719 +to the thread pool that do this job. + +00:19:56.720 --> 00:19:58.119 +And thread pool is going to + +00:19:58.120 --> 00:19:59.719 +assign one thread to it. + +00:19:59.720 --> 00:20:00.959 +Let's say the thread 1 + +00:20:00.960 --> 00:20:03.239 +which is going to render page 56. + +00:20:03.240 --> 00:20:06.559 +So this thread is going to make calls to MuPDF + +00:20:06.560 --> 00:20:08.919 +through our code dynamic module. + +00:20:08.920 --> 00:20:11.839 +And MuPDF after rendering it + +00:20:11.840 --> 00:20:13.439 +is going to store it in the cache. + +00:20:13.440 --> 00:20:18.059 +So we're going to add another 56 page to this. + +00:20:18.060 --> 00:20:21.759 +Now, while this is happening, + +00:20:21.760 --> 00:20:24.679 +Emacs Reader does not, like Emacs itself, + +00:20:24.680 --> 00:20:27.379 +the session is not going to be stuck + +00:20:27.380 --> 00:20:30.239 +because we just made a call to the thread. + +00:20:30.240 --> 00:20:32.279 +We just asked the thread. + +00:20:32.280 --> 00:20:35.359 +So like this, this call, like it's done. + +00:20:35.360 --> 00:20:38.159 +So you just assign something to a thread + +00:20:38.160 --> 00:20:40.959 +and then this is fine. + +00:20:40.960 --> 00:20:42.479 +Like, you're not waiting for the thread + +00:20:42.480 --> 00:20:43.719 +to complete or anything. + +00:20:43.720 --> 00:20:46.519 +Emacs is not waiting for the thread to complete. + +00:20:46.520 --> 00:20:48.519 +The dynamic module or the C side + +00:20:48.520 --> 00:20:49.479 +might wait to complete + +00:20:49.480 --> 00:20:51.279 +but that is entirely different from + +00:20:51.280 --> 00:20:52.159 +the Emacs session. + +00:20:52.160 --> 00:20:54.839 +So Emacs viewer can continue to + +00:20:54.840 --> 00:20:56.279 +display the page 50 + +00:20:56.280 --> 00:20:58.599 +while the rendering pipeline + +00:20:58.600 --> 00:21:01.979 +is still rendering the 56th page. + +00:21:01.980 --> 00:21:05.759 +And when Emacs asks to display page 56, + +00:21:05.760 --> 00:21:09.619 +it's going to ask it to a thread pool. + +00:21:09.620 --> 00:21:11.536 +Then thread pool is going to assign + +00:21:11.537 --> 00:21:13.319 +another thread, let's say this one, + +00:21:13.320 --> 00:21:16.999 +to retrieve page 56 from the memory cache. + +00:21:17.000 --> 00:21:20.039 +And then the 56 page is going to be sent + +00:21:20.040 --> 00:21:24.559 +to the Emacs to be displayed. + +00:21:24.560 --> 00:21:26.039 +Again, the retrieval part + +00:21:26.040 --> 00:21:28.519 +is entirely independent of Emacs. + +00:21:28.520 --> 00:21:30.159 +Emacs does not have to wait for it. + +00:21:30.160 --> 00:21:34.719 +Emacs only needs to wait to display it. + +00:21:34.720 --> 00:21:36.619 +So, the displaying part + +00:21:36.620 --> 00:21:37.919 +and the rendering pipeline + +00:21:37.920 --> 00:21:41.559 +are entirely asynchronous, so to speak. + +00:21:41.560 --> 00:21:43.639 +And in the diagram, if you see, + +00:21:43.640 --> 00:21:46.399 +all the arrows that are + +00:21:46.400 --> 00:21:48.839 +magenta in color, + +00:21:48.840 --> 00:21:51.639 +they are native to the Emacs runtime. + +00:21:51.640 --> 00:21:53.959 +That is, they are single-threaded. + +00:21:53.960 --> 00:21:55.679 +They are connected to Emacs. + +00:21:55.680 --> 00:21:58.759 +And all the arrows that are red in color, + +00:21:58.760 --> 00:22:01.859 +they are totally asynchronous. + +00:22:01.860 --> 00:22:03.519 +They can be multi-threaded if you want. + +00:22:03.520 --> 00:22:05.759 +They are multi-threaded by default + +00:22:05.760 --> 00:22:07.679 +because they interact + +00:22:07.680 --> 00:22:09.519 +only with the MuPDF shared library + +00:22:09.520 --> 00:22:11.399 +and the C heap. + +00:22:11.400 --> 00:22:12.719 +They do not touch anything + +00:22:12.720 --> 00:22:14.639 +in the Emacs runtime. + +00:22:14.640 --> 00:22:18.959 +This is how we're able to switch quickly + +00:22:18.960 --> 00:22:22.519 +between these huge scanned PDFs + +00:22:22.520 --> 00:22:23.959 +that have huge images + +00:22:23.960 --> 00:22:25.359 +in each of their pages + +00:22:25.360 --> 00:22:28.079 +because we don't really wait for + +00:22:28.080 --> 00:22:31.379 +each page to be rendered. + +00:22:31.380 --> 00:22:35.359 +And Emacs does not wait for that. + +00:22:35.360 --> 00:22:39.239 +So that's another architectural feature + +00:22:39.240 --> 00:22:40.319 +of Emacs Reader + +00:22:40.320 --> 00:22:43.199 +that we are system-level multithreaded. + +00:22:43.200 --> 00:22:47.399 +Now Emacs viewer also supports + +00:22:47.400 --> 00:22:49.319 +almost all document formats. + +00:22:49.320 --> 00:22:54.759 +It supports PDF, EPUB, MOBI, XPS, CPZ comics, + +00:22:54.760 --> 00:22:56.439 +and it even supports + +00:22:56.440 --> 00:22:59.970 +other non-ebook formats + +00:22:59.971 --> 00:23:00.839 +like document format, + +00:23:00.840 --> 00:23:01.839 +so you can open + +00:23:01.840 --> 00:23:04.799 +LibreOffice documents in it, + +00:23:04.800 --> 00:23:07.079 +and even stuff like PPT and Excel in it, + +00:23:07.080 --> 00:23:08.759 +even though they're not going to be + +00:23:08.760 --> 00:23:13.859 +supported in a as nice manner. + +00:23:13.860 --> 00:23:16.239 +And we can do that because MuPDF does this. + +00:23:16.240 --> 00:23:18.079 +MuPDF has support for all of this + +00:23:18.080 --> 00:23:22.679 +and it treats them just as it treats PDF. + +00:23:22.680 --> 00:23:24.539 +Nothing special. + +00:23:24.540 --> 00:23:26.519 +The only thing that we don't support right now + +00:23:26.520 --> 00:23:30.159 +is DejaVu, so that is not supported right now. + +00:23:30.160 --> 00:23:33.319 +I'm going to work on making it supported + +00:23:33.320 --> 00:23:35.079 +at the upstream MuPDF. + +00:23:36.020 --> 00:23:38.439 +That's going to take a long time, + +00:23:38.440 --> 00:23:44.239 +but it's in the plans. + +NOTE Native Emacs integrations + +00:23:44.240 --> 00:23:45.439 +Now with Emacs Reader, + +00:23:45.440 --> 00:23:46.679 +we also integrate + +00:23:46.680 --> 00:23:48.619 +with existing Emacs packages + +00:23:48.620 --> 00:23:50.039 +as much as possible. + +00:23:50.040 --> 00:23:52.999 +So bookmarks, C-x r b, + +00:23:53.000 --> 00:23:54.359 +you can do it natively. + +00:23:54.360 --> 00:23:57.559 +So you can save a page as a bookmark + +00:23:57.560 --> 00:23:59.639 +just as you save anything else in Emacs + +00:23:59.640 --> 00:24:00.519 +as a bookmark. + +00:24:00.520 --> 00:24:02.599 +There's also saveplace integration. + +00:24:02.600 --> 00:24:06.159 +So you can scroll a PDF, close it, + +00:24:06.160 --> 00:24:07.599 +and then come back to it + +00:24:07.600 --> 00:24:10.159 +at the same page that you saved it at. + +00:24:10.160 --> 00:24:12.879 +Sorry, that you closed it at. + +00:24:12.880 --> 00:24:14.919 +And it's going to work just out of the box + +00:24:14.920 --> 00:24:16.399 +because of the saveplace + +00:24:16.400 --> 00:24:18.999 +package in Emacs that is built in. + +00:24:19.000 --> 00:24:20.919 +We also have imenu integration + +00:24:20.920 --> 00:24:22.479 +for table of contents. + +00:24:22.480 --> 00:24:26.719 +So if you see this, this is imenu + +00:24:26.720 --> 00:24:28.679 +and you can scroll through the contents + +00:24:28.680 --> 00:24:30.559 +just like you scroll through any imenu. + +00:24:30.560 --> 00:24:39.499 +You can also do it in the menu bar by clicking. + +00:24:39.500 --> 00:24:40.679 +It works just as nice. + +00:24:40.680 --> 00:24:42.739 +We also have something like + +00:24:42.740 --> 00:24:44.799 +the outline mode that pdf-tools has. + +00:24:44.800 --> 00:24:48.039 +So if you press O in a document, + +00:24:48.040 --> 00:24:49.959 +it's going to give you this outline. + +00:24:49.960 --> 00:24:53.399 +And these are buttons that are clickable. + +00:24:53.400 --> 00:24:54.439 +You can click them. + +00:24:54.440 --> 00:24:56.519 +You can press Enter at them. + +00:24:56.520 --> 00:25:00.359 +And this is the menu bar item that I was looking at. + +00:25:00.360 --> 00:25:01.999 +If you click here, index, + +00:25:02.000 --> 00:25:03.279 +it's going to show you + +00:25:03.280 --> 00:25:05.339 +the exact same thing + +00:25:05.340 --> 00:25:10.339 +but in a different interface. + +NOTE (Naive) dark mode + +00:25:10.340 --> 00:25:15.259 +We also have a naive dark mode, + +00:25:15.260 --> 00:25:17.799 +which is not really as nice as + +00:25:17.800 --> 00:25:18.599 +we would like it to be, + +00:25:18.600 --> 00:25:20.799 +and dark mode fanatics + +00:25:20.800 --> 00:25:22.199 +I'm sure will have issues with it, + +00:25:22.200 --> 00:25:24.199 +but we're going to improve it in time. + +00:25:24.200 --> 00:25:27.379 +For now, this is what we have. + +00:25:27.380 --> 00:25:30.359 +And it can be enabled per document, + +00:25:30.360 --> 00:25:33.099 +so you can have one, like, + +00:25:33.100 --> 00:25:34.879 +one document that is in dark mode, + +00:25:34.880 --> 00:25:36.439 +but another one that is not. + +00:25:36.440 --> 00:25:39.279 +That is nice to have. + +00:25:39.280 --> 00:25:42.679 +Eventually we're going to work on more themes. + +00:25:42.680 --> 00:25:46.479 +You should be able to actually integrate it + +00:25:46.480 --> 00:25:49.439 +with Emacs themes as much as possible. + +00:25:49.440 --> 00:25:52.679 +You can make it default so that + +00:25:52.680 --> 00:25:54.839 +it inherits colors from the Emacs theme. + +00:25:54.840 --> 00:25:56.359 +That is one of the things + +00:25:56.360 --> 00:26:01.139 +that we also have planned. + +NOTE Challenges and further improvements + +00:26:01.140 --> 00:26:03.439 +We did face a bunch of challenges + +00:26:03.440 --> 00:26:05.519 +while trying to implement these features. + +00:26:05.520 --> 00:26:07.519 +One of the initial challenges was that + +00:26:07.520 --> 00:26:09.319 +SVGs were actually a bad idea. + +00:26:09.320 --> 00:26:12.159 +They're huge, especially in scanned PDFs, + +00:26:12.160 --> 00:26:14.679 +and they make things much slower. + +00:26:14.680 --> 00:26:18.119 +So we chose to actually have PPMs, + +00:26:18.120 --> 00:26:24.099 +which is the simplest image format ever possible. + +00:26:24.100 --> 00:26:26.439 +Now, it was also very difficult + +00:26:26.440 --> 00:26:29.559 +to make reader-mode be window-specific. + +00:26:29.560 --> 00:26:31.559 +So, you know, while you're scrolling + +00:26:31.560 --> 00:26:34.279 +the same document in one window, + +00:26:34.280 --> 00:26:36.199 +the other window with the same document + +00:26:36.200 --> 00:26:37.039 +should not change. + +00:26:37.040 --> 00:26:39.079 +We should be able to have multiple pages + +00:26:39.080 --> 00:26:42.319 +in different windows of the same document. + +00:26:42.320 --> 00:26:44.679 +That was very difficult + +00:26:44.680 --> 00:26:46.679 +because as I told you about the cache, + +00:26:46.680 --> 00:26:50.599 +the cache works in an idiosyncratic manner + +00:26:50.600 --> 00:26:54.079 +and we needed to make it so that each window + +00:26:54.080 --> 00:26:56.559 +will have its own cache + +00:26:56.560 --> 00:27:01.199 +instead of having a global cache for each file. + +00:27:01.200 --> 00:27:03.799 +That took some rewrite. + +00:27:03.800 --> 00:27:06.879 +And now, because we needed to do + +00:27:06.880 --> 00:27:07.799 +this sort of multithreading, + +00:27:07.800 --> 00:27:08.999 +system-level multithreading, + +00:27:09.000 --> 00:27:10.919 +we needed to use + +00:27:10.920 --> 00:27:13.039 +a specific package of MuPDF + +00:27:13.040 --> 00:27:16.439 +that had a bug for this which got fixed. + +00:27:16.440 --> 00:27:20.719 +And that's 1.26.0. + +00:27:20.720 --> 00:27:23.336 +Because we did that, + +00:27:23.337 --> 00:27:26.462 +a lot of the GNU/Linux distributions did not + +00:27:26.463 --> 00:27:28.871 +really have this latest package. + +00:27:28.872 --> 00:27:30.771 +So we had to actually + +00:27:30.772 --> 00:27:33.804 +package it in-tree. + +00:27:33.805 --> 00:27:36.971 +as a git sub-module. + +00:27:36.972 --> 00:27:40.737 +That was a horror! But eventually... now + +00:27:40.738 --> 00:27:43.604 +I think most GNU/Linux distributions + +00:27:43.605 --> 00:27:46.340 +already have this [version]. + +00:27:46.341 --> 00:27:48.639 +The upcoming features that we have planned + +00:27:48.640 --> 00:27:52.799 +are the first one is that we need to rewrite + +00:27:52.800 --> 00:27:55.359 +the display mechanism entirely from scratch + +00:27:55.360 --> 00:27:57.559 +to use a tiled rendering approach. + +00:27:57.560 --> 00:27:59.999 +So right now we just take an image + +00:28:00.000 --> 00:28:02.959 +and display it inside an Emacs buffer + +00:28:02.960 --> 00:28:03.959 +just like that. + +00:28:03.960 --> 00:28:08.759 +But it will be changed so that the image + +00:28:08.760 --> 00:28:10.759 +will be displayed in the tiled manner + +00:28:10.760 --> 00:28:12.479 +so there will be multiple tiles + +00:28:12.480 --> 00:28:14.719 +but it'll be pixel perfect + +00:28:14.720 --> 00:28:16.399 +so you won't really see a difference. + +00:28:16.400 --> 00:28:19.839 +The reason to do this is to implement features + +00:28:19.840 --> 00:28:20.999 +for text selection, actually. + +00:28:21.000 --> 00:28:24.239 +So we can't really do text selection + +00:28:24.240 --> 00:28:27.079 +without running into a bunch of memory + +00:28:27.080 --> 00:28:29.999 +and other issues latency issues + +00:28:30.000 --> 00:28:33.019 +if we don't do tiling. + +00:28:33.020 --> 00:28:35.679 +So we need to do those two things, + +00:28:35.680 --> 00:28:38.879 +they are at the highest priority right now. + +00:28:38.880 --> 00:28:40.279 +And then, once we're done with that, + +00:28:40.280 --> 00:28:42.279 +we're going to support annotations, + +00:28:42.280 --> 00:28:45.439 +highlighting, everything that you're used to + +00:28:45.440 --> 00:28:47.319 +in pdf-tools and org-noter. + +00:28:47.320 --> 00:28:50.119 +And once we're done with that, + +00:28:50.120 --> 00:28:55.019 +we're going to also integrate with AucTeX and SyncTeX. + +00:28:55.020 --> 00:28:58.519 +Because right now, when a PDF gets updated, + +00:28:58.520 --> 00:29:00.239 +especially a LaTeX PDF, + +00:29:00.240 --> 00:29:03.437 +since there is no SyncTeX integration, + +00:29:03.438 --> 00:29:05.771 +it can't really do it nicely + +00:29:05.772 --> 00:29:08.660 +and it sometimes even crashes Emacs. + +00:29:08.661 --> 00:29:11.537 +So that's something that + +00:29:11.538 --> 00:29:14.271 +we will be planning to implement. + +NOTE What Emacs can learn? + +00:29:14.272 --> 00:29:16.159 +Now, from this experiment, + +00:29:16.160 --> 00:29:17.919 +what exactly can Emacs, + +00:29:17.920 --> 00:29:20.519 +the Emacs core devs and others + +00:29:20.520 --> 00:29:22.399 +who are building packages can learn? + +00:29:22.400 --> 00:29:24.919 +Well, the first thing is that all of this + +00:29:24.920 --> 00:29:27.159 +should not be really this difficult + +00:29:27.160 --> 00:29:30.359 +because all we're asking from Emacs + +00:29:30.360 --> 00:29:32.439 +is to display images in real-time + +00:29:32.440 --> 00:29:36.279 +and update them in real-time. + +00:29:36.280 --> 00:29:37.759 +That should not be that difficult + +00:29:37.760 --> 00:29:40.279 +of a thing to do, but apparently it is. + +00:29:40.280 --> 00:29:43.279 +And that's why Emacs's graphical interface + +00:29:43.280 --> 00:29:47.959 +needs to be more modular, more composable, + +00:29:47.960 --> 00:29:50.999 +and flexible for real-time graphics. + +00:29:51.000 --> 00:29:54.219 +If it is supposed to have things like, + +00:29:54.220 --> 00:29:56.179 +again, a document reader, + +00:29:56.180 --> 00:29:57.279 +something like a video editor, + +00:29:57.280 --> 00:29:58.239 +and something like that, + +00:29:58.980 --> 00:30:00.479 +Emacs's graphical interface + +00:30:00.480 --> 00:30:05.239 +needs to grow and be more mature. + +00:30:05.240 --> 00:30:06.239 +One of the things + +00:30:06.240 --> 00:30:08.079 +that's stopping it from doing that + +00:30:08.080 --> 00:30:10.319 +is actually Emacs's overlay functionality. + +00:30:10.320 --> 00:30:13.939 +So right now, the way we display + +00:30:13.940 --> 00:30:16.519 +an image in a buffer + +00:30:16.520 --> 00:30:18.900 +is using an overlay, + +00:30:18.901 --> 00:30:22.019 +actually multiple overlays. + +00:30:22.020 --> 00:30:25.839 +Overlays are static in the sense that + +00:30:25.840 --> 00:30:29.739 +if I attach to one image to one overlay, + +00:30:29.740 --> 00:30:34.039 +I need to have an entirely different image + +00:30:34.040 --> 00:30:37.199 +updated for that overlay. + +00:30:37.200 --> 00:30:39.639 +So I need to create another different image, + +00:30:39.640 --> 00:30:41.179 +change it in the memory, + +00:30:41.180 --> 00:30:43.639 +and then display it to update it. + +00:30:43.640 --> 00:30:46.639 +I can't change the image data + +00:30:46.640 --> 00:30:49.239 +in real time of the overlay. + +00:30:49.240 --> 00:30:53.999 +And that is a big issue. + +00:30:54.000 --> 00:30:56.259 +I've actually made an emacs-devel + +00:30:56.260 --> 00:30:58.279 +mailing list thread about it. + +00:30:58.280 --> 00:31:01.119 +I talked to Eli about it as well. + +00:31:01.120 --> 00:31:04.639 +And he said there's a possibility + +00:31:04.640 --> 00:31:05.359 +that this can be changed, + +00:31:05.360 --> 00:31:06.959 +but it's going to take + +00:31:06.960 --> 00:31:09.919 +a certain amount of rewrite. + +00:31:09.920 --> 00:31:12.319 +There's also issues with Emacs GC. + +00:31:12.320 --> 00:31:14.639 +Emacs GC sometimes leaks memory + +00:31:14.640 --> 00:31:16.439 +when you update images too quickly. + +00:31:16.440 --> 00:31:18.599 +That is, when you have a bunch of images + +00:31:18.600 --> 00:31:21.359 +that are getting churned out too quickly, + +00:31:21.360 --> 00:31:23.039 +Emacs GC starts leaking + +00:31:23.040 --> 00:31:25.159 +and it just goes up to + +00:31:25.160 --> 00:31:29.679 +a huge number of gigabytes in RAM. + +00:31:29.680 --> 00:31:32.399 +That's also a huge problem. + +00:31:32.400 --> 00:31:33.759 +The dynamic module API, + +00:31:33.760 --> 00:31:37.139 +the emacs-module.h header, + +00:31:37.140 --> 00:31:38.799 +needs to have more helpers. + +00:31:38.800 --> 00:31:41.719 +It's really bare bones, + +00:31:41.720 --> 00:31:43.439 +and I like that it is bare bones + +00:31:43.440 --> 00:31:44.999 +so that other languages can use it, + +00:31:45.000 --> 00:31:46.959 +but at the same time, I think + +00:31:46.960 --> 00:31:47.879 +it'll be really good + +00:31:47.880 --> 00:31:49.839 +if we can have some helpers + +00:31:49.840 --> 00:31:53.879 +that can do better memory interaction, + +00:31:53.880 --> 00:31:57.259 +like strings and so on, + +00:31:57.260 --> 00:32:00.379 +which we also faced some issues with. + +00:32:00.380 --> 00:32:02.319 +Emacs's fractional scaling system + +00:32:02.320 --> 00:32:05.359 +seems to be broken across different toolkits. + +00:32:05.360 --> 00:32:10.999 +We have bug reports that say in pgtk in Wayland, + +00:32:11.000 --> 00:32:13.559 +something seems to render differently + +00:32:13.560 --> 00:32:17.259 +because they have fractional scaling enabled. + +00:32:17.260 --> 00:32:18.439 +So that's something + +00:32:18.440 --> 00:32:21.239 +that I think Emacs, overall, + +00:32:21.240 --> 00:32:24.359 +I think Emacs needs to focus on improving + +00:32:24.360 --> 00:32:28.239 +the graphical interface pipeline + +00:32:28.240 --> 00:32:32.299 +to be a much more mature one. + +NOTE Contributing to the development + +00:32:32.300 --> 00:32:34.239 +And finally, how can you contribute + +00:32:34.240 --> 00:32:35.799 +to the development of Emacs Reader? + +00:32:35.800 --> 00:32:37.359 +Well, we are on Codeberg. + +00:32:37.360 --> 00:32:40.279 +We are not on GitHub, sorry. + +00:32:40.280 --> 00:32:41.639 +You can go there, + +00:32:41.640 --> 00:32:43.079 +you can look through the issues + +00:32:43.080 --> 00:32:45.279 +and send us a PR if you're interested. + +00:32:45.280 --> 00:32:46.879 +The next major release + +00:32:46.880 --> 00:32:49.839 +is going to go to GNU ELPA. + +00:32:49.840 --> 00:32:52.259 +Finally, we are not yet at GNU ELPA, + +00:32:52.260 --> 00:32:54.439 +so you can't really do M-x package-install + +00:32:54.440 --> 00:32:56.119 +and install our package. + +00:32:56.120 --> 00:32:58.199 +you would need to install it + +00:32:58.200 --> 00:33:04.939 +through use-package-:vc. + +00:33:04.940 --> 00:33:07.499 +And since we're going to go to GNU ELPA, + +00:33:07.500 --> 00:33:09.119 +we request you to assign + +00:33:09.120 --> 00:33:10.519 +your copyright to Emacs + +00:33:10.520 --> 00:33:13.959 +because GNU ELPA is essentially part of GNU Emacs. + +00:33:13.960 --> 00:33:16.719 +So you would need to do copyright assignment + +00:33:16.720 --> 00:33:20.579 +if you make non-trivial contribution. + +00:33:20.580 --> 00:33:22.479 +You can join us at IRC + +00:33:22.480 --> 00:33:24.359 +at #phi-mu-lambda. + +00:33:24.360 --> 00:33:27.199 +And I also stream the development + +00:33:27.200 --> 00:33:28.039 +of this package + +00:33:28.040 --> 00:33:29.839 +bi-weekly on Sundays + +00:33:29.840 --> 00:33:31.639 +at PeerTube at the following channel. + +00:33:31.640 --> 00:33:35.519 +Feel free to join us. + +NOTE Acknowledgements + +00:33:35.520 --> 00:33:38.499 +Finally, I want to thank Tushar, + +00:33:38.500 --> 00:33:40.639 +who has been persistently contributing + +00:33:40.640 --> 00:33:42.839 +to the project since 0.1.0, + +00:33:42.840 --> 00:33:46.519 +and I'm very, very thankful for him, + +00:33:46.520 --> 00:33:47.759 +for his suggestions, + +00:33:47.760 --> 00:33:50.879 +and for his code contributions as well. + +00:33:50.880 --> 00:33:53.319 +I would also like to thank Prom, + +00:33:53.320 --> 00:33:55.799 +who fixed a major bug + +00:33:55.800 --> 00:33:56.859 +in the Windows build, + +00:33:56.860 --> 00:33:58.839 +since I don't really use Windows anymore, + +00:33:58.840 --> 00:33:59.919 +so that was really nice, + +00:33:59.920 --> 00:34:05.459 +and for Teeoius, for fixing a pthread bug. + +00:34:05.460 --> 00:34:06.919 +I would also like to thank others + +00:34:06.920 --> 00:34:09.559 +who helped fix little things, + +00:34:09.560 --> 00:34:13.179 +who come to the stream to chat, + +00:34:13.180 --> 00:34:16.599 +who sort of see me bang my head + +00:34:16.600 --> 00:34:19.239 +across these C memory bugs. + +00:34:19.240 --> 00:34:21.599 +So thank you to all of those. + +00:34:21.600 --> 00:34:24.399 +And thank you finally to the viewers + +00:34:24.400 --> 00:34:28.079 +and to EmacsConf organizers as well. + +00:34:28.080 --> 00:34:31.939 +This is a splendid opportunity. + +00:34:31.940 --> 00:34:37.280 +Thank you. diff --git a/2025/info/reader-after.md b/2025/info/reader-after.md index b0f4bf51..37def9ea 100644 --- a/2025/info/reader-after.md +++ b/2025/info/reader-after.md @@ -1,6 +1,828 @@ <!-- Automatically generated by emacsconf-publish-after-page --> +<div class="transcript transcript-mainVideo"><a name="reader-mainVideo-transcript"></a><h1>Transcript</h1> + + +<div class="transcript-heading">[[!template new="1" text="""An introduction to the Emacs reader""" start="00:00:00.720" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Hello EmacsConf!""" start="00:00:00.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Today I'm here to introduce you to the Emacs Reader.""" start="00:00:02.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It is a general-purpose document viewer""" start="00:00:06.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that lives inside our beloved Emacs.""" start="00:00:08.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It tries to prioritize memory""" start="00:00:12.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and performance efficiency as much as possible""" start="00:00:14.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""even when you're using a lower-end hardware.""" start="00:00:17.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And, most importantly,""" start="00:00:20.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it tries to do things in an Emacs manner.""" start="00:00:22.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That is, it tries to integrate""" start="00:00:25.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""with existing packages as much as possible""" start="00:00:27.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""instead of reinventing the wheel.""" start="00:00:29.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And architecturally, it tries to take the advantage""" start="00:00:32.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of dynamic or native modules""" start="00:00:36.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which were introduced back in 2015 into Emacs.""" start="00:00:38.480" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Yet another document viewer in Emacs?""" start="00:00:44.760" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""You would ask, why exactly do we need""" start="00:00:44.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""another document viewer in Emacs?""" start="00:00:46.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Don't we already have the built-in DocView""" start="00:00:49.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and the notorious pdf-tools?""" start="00:00:51.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Well, the built-in DocView has unusable latency,""" start="00:00:55.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and I'm going to show you this later""" start="00:00:59.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""when I compare this with Emacs Reader.""" start="00:01:01.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The famous pdf-tools has actually multiple issues.""" start="00:01:04.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""One, it is extremely memory-hungry""" start="00:01:08.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""regardless of what kind of PDFs you're reading.""" start="00:01:10.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And, well, it can only read PDFs.""" start="00:01:14.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Poppler, the library which pdf-tools uses,""" start="00:01:17.940" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is actually sub-optimal,""" start="00:01:22.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""especially relative to MuPDF,""" start="00:01:23.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which is what Emacs Reader is based on.""" start="00:01:25.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-tools is also extremely painful to install.""" start="00:01:28.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If you've ever installed pdf-tools,""" start="00:01:31.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you know that it has a bunch of dependencies,""" start="00:01:34.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""including a server that is supposedly packaged.""" start="00:01:38.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""across package managers, system package managers.""" start="00:01:42.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's extremely difficult to install""" start="00:01:45.062" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and painful to install.""" start="00:01:47.738" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And of course, pdf-tools""" start="00:01:50.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""since the last couple of years""" start="00:01:52.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""has not been maintained as much.""" start="00:01:54.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""There's huge PRs that have been unnoticed and unmerged.""" start="00:01:56.560" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Architecture of Emacs Reader""" start="00:02:05.760" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Architecturally, Emacs Reader takes a distance""" start="00:02:05.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""from both DocView and pdf-tools.""" start="00:02:09.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So how DocView works is that""" start="00:02:12.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it basically wraps around""" start="00:02:15.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a tool called mutool.""" start="00:02:18.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""mutool is actually""" start="00:02:20.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a command line tool from MuPDF itself.""" start="00:02:22.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It relies on mutool and a bunch""" start="00:02:26.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of other similar command line tools,""" start="00:02:28.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and basically makes process calls""" start="00:02:30.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""from Elisp to the CLI tools.""" start="00:02:34.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's how DocView works,""" start="00:02:36.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and that's why it sort of has latency issues""" start="00:02:38.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because that's the best you can do""" start="00:02:41.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""by literally calling CLI tools""" start="00:02:42.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and outputting the images into Emacs.""" start="00:02:45.020" video="mainVideo-reader" id="subtitle"]] +[[!template text="""How pdf-tools works is that it tries""" start="00:02:50.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to have a server-client model.""" start="00:02:55.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So the client is Emacs""" start="00:02:57.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and the server is basically""" start="00:02:59.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""something they call epdfinfo.""" start="00:03:00.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's supposed to render the images using Poppler""" start="00:03:03.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then send the images to Emacs""" start="00:03:07.241" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which then tries to display.""" start="00:03:10.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I think the server client model is terrible.""" start="00:03:13.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""One, for latency purposes,""" start="00:03:16.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and two, it makes things""" start="00:03:18.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""unnecessarily more complicated.""" start="00:03:19.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Here is where we come""" start="00:03:21.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and introduce dynamic modules.""" start="00:03:24.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So Emacs Reader is based on""" start="00:03:26.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the concept of dynamic modules""" start="00:03:30.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which I'm going to talk about in a bit.""" start="00:03:32.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But how it works is that we have C modules.""" start="00:03:34.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we have the emacs-module.h,""" start="00:03:37.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that's the dynamic module header""" start="00:03:39.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which every dynamic module package must have.""" start="00:03:40.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And then we have our C files.""" start="00:03:43.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And these C files essentially define functions""" start="00:03:45.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that are going to be used in Emacs but in C.""" start="00:03:52.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We then load these C modules""" start="00:03:56.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""using simple (require ...) in our Elisp modules.""" start="00:03:59.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And then whenever we call""" start="00:04:03.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""something in the Emacs runtime,""" start="00:04:05.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""say I'm going to open""" start="00:04:07.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""PDF files in (find-file) or (reader-open-doc),""" start="00:04:09.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""what it does is that""" start="00:04:13.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it tries to use one of the functions""" start="00:04:15.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is wrapped in Elisp,""" start="00:04:19.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but actually tries to call a function in C.""" start="00:04:21.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And then the C module is actually""" start="00:04:24.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""going to make calls to the MuPDF.""" start="00:04:26.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Here the MuPDF system package,""" start="00:04:29.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""this is actually a system package""" start="00:04:31.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is dynamically linked to the C modules.""" start="00:04:33.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we're basically""" start="00:04:35.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just using it as a shared library.""" start="00:04:36.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you have the fz_load_page, for example,""" start="00:04:39.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it's a MuPDF function""" start="00:04:43.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that we're going to be using in the C modules.""" start="00:04:44.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So it's going to make""" start="00:04:47.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a shared dynamic call to MuPDF""" start="00:04:50.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then render the page""" start="00:04:53.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then show this to Emacs.""" start="00:04:55.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This pipeline, I argue,""" start="00:04:59.180" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is much better and leaner and efficient""" start="00:05:01.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""than a server-client model.""" start="00:05:05.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""One, because we don't really need""" start="00:05:07.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the server-client model.""" start="00:05:09.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So back when Politza""" start="00:05:10.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""first introduced pdf-tools,""" start="00:05:12.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that was like 10 years ago in 2015,""" start="00:05:14.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the concept of dynamic modules""" start="00:05:19.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""were not integrated into Emacs.""" start="00:05:21.241" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I think they came around""" start="00:05:23.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""like one or two years late, 2017.""" start="00:05:24.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's the best he could go with.""" start="00:05:28.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We don't really have to, today,""" start="00:05:31.220" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because, since we can use MuPDF""" start="00:05:33.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as a shared library""" start="00:05:35.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which can render things in real-time""" start="00:05:37.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and just give us the rendered images""" start="00:05:39.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which we can then display,""" start="00:05:41.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""there's no reason for a server to do things for us.""" start="00:05:43.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's the main architectural difference""" start="00:05:49.660" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that Emacs Reader introduces""" start="00:05:53.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""compared to pdf-tools and DocView.""" start="00:05:55.480" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""A word on dynamic modules""" start="00:06:00.280" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""What exactly are dynamic modules?""" start="00:06:00.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Well, I can't really give you""" start="00:06:02.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a full-fledged explanation,""" start="00:06:04.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but essentially dynamic modules""" start="00:06:06.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""let you evaluate""" start="00:06:08.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""native compiled code""" start="00:06:10.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in other languages like C, C++, Rust""" start="00:06:12.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that behaves like regular Emacs Lisp.""" start="00:06:15.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So when our Emacs C modules,""" start="00:06:18.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the render-core.c or render-theme.c,""" start="00:06:23.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""when all of these are compiled,""" start="00:06:26.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and they're called from the Elisp modules.""" start="00:06:28.300" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They behave like Elisp even though""" start="00:06:30.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""they're as fast as a C function""" start="00:06:34.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because they're compiled C code.""" start="00:06:37.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But you essentially call them""" start="00:06:39.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just like Elisp functions.""" start="00:06:41.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can find them using C-h f and so on.""" start="00:06:42.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you can call any function""" start="00:06:47.820" video="mainVideo-reader" id="subtitle"]] +[[!template text="""from any language that supports""" start="00:06:49.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the C ABI, which is virtually everything,""" start="00:06:51.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""without leaving Emacs""" start="00:06:53.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and without losing any performance.""" start="00:06:54.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is extremely helpful""" start="00:06:56.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""when you want to use""" start="00:06:58.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""existing libraries like MuPDF""" start="00:06:59.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""or any other cryptographic library""" start="00:07:02.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is written in C""" start="00:07:04.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and you don't want to rewrite""" start="00:07:06.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the entire thing in Elisp,""" start="00:07:07.038" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but you can just use it as a native library.""" start="00:07:08.538" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can read more""" start="00:07:11.740" video="mainVideo-reader" id="subtitle"]] +[[!template text="""on how dynamic modules work""" start="00:07:13.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and how you can write one in this blog.""" start="00:07:14.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is something that I wrote myself""" start="00:07:17.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just after starting this package""" start="00:07:19.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it will give you a bit more guidance""" start="00:07:22.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""on how to use dynamic modules more efficiently.""" start="00:07:25.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I think dynamic modules""" start="00:07:27.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""should be used more and more in Emacs""" start="00:07:28.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and I think their advantages""" start="00:07:32.300" video="mainVideo-reader" id="subtitle"]] +[[!template text="""have not been exploited""" start="00:07:34.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as much as they should.""" start="00:07:36.080" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Features of Emacs Reader""" start="00:07:39.560" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Now we're going to talk a bit about""" start="00:07:39.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the core features of Emacs Reader.""" start="00:07:42.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And these are the following features""" start="00:07:46.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that we're going to talk about.""" start="00:07:48.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And finally, to talk about""" start="00:07:50.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""some challenges that we faced.""" start="00:07:51.960" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Memory efficiency""" start="00:07:56.760" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""First is memory efficiency.""" start="00:07:56.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I already told you that""" start="00:07:58.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs Reader's first priority""" start="00:08:00.820" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is to make sure that we are not slow""" start="00:08:03.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and we are not taking""" start="00:08:06.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a bunch of memory unnecessarily.""" start="00:08:07.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So here's a graph of the heap memory size""" start="00:08:10.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as it grows for DocView.""" start="00:08:14.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this is again in emacs -Q.""" start="00:08:17.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this is a fresh Emacs session""" start="00:08:20.638" video="mainVideo-reader" id="subtitle"]] +[[!template text="""with just DocView.""" start="00:08:22.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It grows up to 900MB""" start="00:08:25.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for a very small PDF that is a LaTeX PDF.""" start="00:08:27.820" video="mainVideo-reader" id="subtitle"]] +[[!template text="""No scanned huge PDF. It's a 2MB PDF.""" start="00:08:31.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But when I scrolled from the beginning""" start="00:08:36.780" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of the PDF to the end,""" start="00:08:39.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it went up to 900MB.""" start="00:08:41.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's the memory heap size.""" start="00:08:43.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Does pdf-tools make this any better?""" start="00:08:46.820" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It actually doesn't.""" start="00:08:49.700" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, pdf-tools pretty much""" start="00:08:51.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""does the same thing.""" start="00:08:55.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""if you look at it here""" start="00:08:57.220" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just so if you're going to ask me""" start="00:08:58.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""are they two different graphs,""" start="00:09:01.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""or are you just showing me the same graph,""" start="00:09:02.940" video="mainVideo-reader" id="subtitle"]] +[[!template text="""they're actually two different graphs,""" start="00:09:04.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because if you look at the DocView graph""" start="00:09:06.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it uses cairo and it uses librsvg""" start="00:09:08.780" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because docview by default""" start="00:09:11.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""converts the images into SVG.""" start="00:09:13.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The rendered images are SVGs.""" start="00:09:16.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-tools doesn't, so you don't see""" start="00:09:18.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""any librsvg calls here or anything""" start="00:09:20.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this is pdf-tools""" start="00:09:24.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it basically takes up""" start="00:09:25.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the same amount of memory, 900MB,""" start="00:09:27.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and exactly the same operation,""" start="00:09:29.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""exactly the same PDF,""" start="00:09:30.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""exactly scrolling from first to the last.""" start="00:09:32.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Where do we stand?""" start="00:09:36.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Well, we actually do much better.""" start="00:09:37.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So let me zoom in this.""" start="00:09:40.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if you see, we stand within""" start="00:09:42.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""at a peak of 72MB.""" start="00:09:46.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Exactly the same PDF,""" start="00:09:49.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""exactly the same operation""" start="00:09:51.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""from the beginning to the end,""" start="00:09:53.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""around 285 pages scrolled.""" start="00:09:54.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We take much less than 80 MB.""" start="00:09:57.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And actually, to be very frank,""" start="00:10:03.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the only memory that we're storing in Emacs,""" start="00:10:05.072" video="mainVideo-reader" id="subtitle"]] +[[!template text="""oh, sorry, not in Emacs,""" start="00:10:09.205" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the MuPDF heap is just about 30 MB.""" start="00:10:12.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's this dark red one.""" start="00:10:16.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's the cache that we're storing.""" start="00:10:19.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's the memory that we're interacting with""" start="00:10:22.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in real time.""" start="00:10:24.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is stuff that Emacs adds on top of it""" start="00:10:25.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and a bit of libmupdf.""" start="00:10:29.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you can see, in terms of memory,""" start="00:10:32.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we're saving...""" start="00:10:35.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we're literally down,""" start="00:10:37.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""what, a fraction of 10!""" start="00:10:41.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This was a priority for us""" start="00:10:45.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""since the beginning,""" start="00:10:48.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because when I was starting to use pdf-tools,""" start="00:10:49.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it was unusable for me""" start="00:10:52.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because I was on a lower-end hardware""" start="00:10:53.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and I thought it should not be""" start="00:10:55.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""really that difficult""" start="00:10:57.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for a document reader""" start="00:10:58.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to not take a gigabyte of memory.""" start="00:11:00.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It really shouldn't because""" start="00:11:04.100" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you're not really doing that much,""" start="00:11:05.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you're just displaying images.""" start="00:11:07.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's how efficient""" start="00:11:10.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we are in terms of memory.""" start="00:11:12.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Let's see how efficient""" start="00:11:13.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we are in terms of speed.""" start="00:11:15.372" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Performance and speed""" start="00:11:18.720" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""So Emacs Reader is actually""" start="00:11:18.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as fast as pdf-tools,""" start="00:11:21.100" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it is actually""" start="00:11:23.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""way more faster than DocView.""" start="00:11:24.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""In some cases,""" start="00:11:27.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it actually beats existing""" start="00:11:28.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""standalone document readers and browsers.""" start="00:11:31.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So let's actually see this in action.""" start="00:11:34.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So here we are with""" start="00:11:41.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a few emacs -Q sessions.""" start="00:11:42.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm using emacs -Q so as to give you...""" start="00:11:46.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that this is actually""" start="00:11:50.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as less overhead possible.""" start="00:11:52.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we have first DocView.""" start="00:11:55.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""All of these tests""" start="00:11:57.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""are going to be done on the same PDF.""" start="00:12:01.138" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's the documentation manual from MuPDF.""" start="00:12:03.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if I scroll, this is fine.""" start="00:12:07.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm just pressing n""" start="00:12:10.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it seems to work fine.""" start="00:12:12.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If I press and hold n,""" start="00:12:15.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I have pressed n and I'm holding.""" start="00:12:19.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And Emacs is stuck.""" start="00:12:21.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And it's going to stay stuck""" start="00:12:26.420" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because it's making calls""" start="00:12:27.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to the CLI tool that I said, mutool.""" start="00:12:28.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And after it's done getting stuck,""" start="00:12:31.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it is going to get back.""" start="00:12:35.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""As you can see, if you go back,""" start="00:12:40.180" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you're able to go back fine.""" start="00:12:43.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It does not get stuck""" start="00:12:45.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because what Emacs does""" start="00:12:46.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is it basically calls mutool,""" start="00:12:48.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""like fetches a bunch of pages,""" start="00:12:51.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""essentially all the pages""" start="00:12:53.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that you asked for it,""" start="00:12:54.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it puts them into the memory.""" start="00:12:56.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And that's it.""" start="00:12:59.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It puts them into the memory""" start="00:12:59.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then scrolls through it.""" start="00:13:01.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So going back, you will most likely""" start="00:13:03.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""not have any stuck issues.""" start="00:13:05.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Sometimes you do""" start="00:13:07.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because some images do get GC'd.""" start="00:13:07.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But that's the idea.""" start="00:13:10.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Whenever there's no image in memory,""" start="00:13:13.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it gets stuck.""" start="00:13:16.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And it gets stuck good.""" start="00:13:18.740" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's DocView.""" start="00:13:21.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-tools is actually""" start="00:13:23.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""not problematic here.""" start="00:13:25.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-tools is extremely efficient""" start="00:13:27.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and extremely fast.""" start="00:13:29.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we can go through the pages""" start="00:13:30.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""without any issues.""" start="00:13:32.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We can zoom.""" start="00:13:34.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The zoom did get stuck a bit,""" start="00:13:37.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but that's relatively fine.""" start="00:13:39.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs Reader is exactly as fast""" start="00:13:44.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as pdf-tools here.""" start="00:13:46.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this is pdf-view,""" start="00:13:49.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""this is Emacs Reader.""" start="00:13:50.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Let's scroll through the pages.""" start="00:13:51.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""As you can see, nothing is getting stuck""" start="00:13:55.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because we're not really waiting""" start="00:13:59.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for any tool to send us any images.""" start="00:14:00.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We just have a little cache""" start="00:14:06.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and we're scrolling through them""" start="00:14:08.300" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and rendering images in real time.""" start="00:14:09.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Zooming also works fine.""" start="00:14:13.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, with regards to this,""" start="00:14:17.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we're in parity with pdf-tools.""" start="00:14:19.520" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Scanned PDFs""" start="00:14:23.680" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Now, where pdf-tools and actually""" start="00:14:23.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a lot of readers have issues""" start="00:14:26.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is when they're dealing with scanned PDF.""" start="00:14:28.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, we have this PDF which is notorious""" start="00:14:32.500" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for being really difficult to render""" start="00:14:36.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because this is entirely built""" start="00:14:40.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""with scanned images.""" start="00:14:42.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is the kind of PDF""" start="00:14:43.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that you get from Internet Archive.""" start="00:14:44.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is essentially someone""" start="00:14:46.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""took photos of the book in a camera""" start="00:14:47.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and literally turned them into a PDF.""" start="00:14:50.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs Reader actually does not have""" start="00:14:56.660" video="mainVideo-reader" id="subtitle"]] +[[!template text="""any issues rendering this.""" start="00:14:58.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""As you can see, it renders it smoothly""" start="00:15:01.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and fine without any halts.""" start="00:15:05.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I can change Emacs even while it's doing so,""" start="00:15:09.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it does not have any issues.""" start="00:15:13.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-tools are the same.""" start="00:15:17.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""PDF also does not have any issues.""" start="00:15:20.072" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Sorry. Click pdf-view-mode.""" start="00:15:21.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""pdf-view (pdf-tools) is a bit slower""" start="00:15:26.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but does not have any issues. It works.""" start="00:15:29.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Here, actually, pdf-tools and Emacs Reader""" start="00:15:35.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""are more efficient than even browsers.""" start="00:15:40.701" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, if I try to open""" start="00:15:46.100" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the same page in a browser,""" start="00:15:47.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm trying to scroll.""" start="00:15:50.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And after I've scrolled and I leave,""" start="00:15:52.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""scrolling is going to load""" start="00:15:54.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for a bunch of seconds""" start="00:15:58.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to give me the page.""" start="00:15:59.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's more than five seconds,""" start="00:16:03.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as you can see,""" start="00:16:04.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and this is actually totally not usable.""" start="00:16:05.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If you're going to read this book,""" start="00:16:08.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""an electromagnetics book,""" start="00:16:10.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you're going to have a terrible time""" start="00:16:12.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""reading this in a browser,""" start="00:16:13.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which is supposed to be""" start="00:16:14.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the fastest thing alive.""" start="00:16:15.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You sort of have the same experience""" start="00:16:17.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in Okular. So this is Okular.""" start="00:16:19.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If I try to scroll through this,""" start="00:16:20.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it will do the same thing.""" start="00:16:22.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And while it is better than the browser,""" start="00:16:25.420" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it still takes a while""" start="00:16:28.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it still has, like, if you zoom,""" start="00:16:31.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you're going to have a bit of a delay.""" start="00:16:34.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You don't really face that in Emacs Reader.""" start="00:16:36.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We zoom in and out just fine.""" start="00:16:41.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And even with using mouse,""" start="00:16:45.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you can zoom in and out just fine.""" start="00:16:47.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this is how Emacs Reader performs""" start="00:16:51.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in terms of speed with these other tools.""" start="00:16:54.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now we will go back to the original presentation.""" start="00:17:01.120" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""System-level multi-threading""" start="00:17:08.960" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Now, how exactly is Emacs Reader""" start="00:17:08.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""able to do a lot of this?""" start="00:17:11.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I wish I could sort of spend""" start="00:17:14.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""an entire session""" start="00:17:17.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just talking about this, but I can't.""" start="00:17:19.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So I'm just going to make this short.""" start="00:17:21.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""When you load Emacs Reader,""" start="00:17:22.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the standard output,""" start="00:17:24.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it's going to say this:""" start="00:17:26.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that eight threads have been initialized.""" start="00:17:27.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now, what we did with Emacs here""" start="00:17:29.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is that we enabled""" start="00:17:32.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""system-level multithreading.""" start="00:17:33.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now, Emacs is not multithreaded.""" start="00:17:35.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We all know that notoriously.""" start="00:17:36.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It is single-threaded.""" start="00:17:38.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But we don't really""" start="00:17:39.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""need Emacs to be multithreaded, though.""" start="00:17:41.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs does not need to be multithreaded.""" start="00:17:43.820" video="mainVideo-reader" id="subtitle"]] +[[!template text="""What needs to be multithreaded""" start="00:17:45.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is the rendering part""" start="00:17:47.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because that's the most expensive part.""" start="00:17:48.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""In Emacs, we're only just displaying images.""" start="00:17:50.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs itself does not have a PDF engine""" start="00:17:53.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is rendering stuff.""" start="00:17:56.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""MuPDF is supposed to take care of that.""" start="00:17:57.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if I can do multithreading""" start="00:18:00.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the rendering pipeline,""" start="00:18:03.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is when I'm rendering pages""" start="00:18:05.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""instead of displaying them,""" start="00:18:07.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that's fine for me because""" start="00:18:08.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the rendering part most of the time,""" start="00:18:10.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""especially in scanned PDFs,""" start="00:18:11.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is the most expensive part.""" start="00:18:12.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if you look at this graph,""" start="00:18:14.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we have two parts here.""" start="00:18:16.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We have the display pipeline""" start="00:18:17.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and we have the rendering pipeline.""" start="00:18:19.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""In the display pipeline,""" start="00:18:22.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we have just the Emacs session""" start="00:18:23.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which has the reader loaded""" start="00:18:26.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and that's the main thread.""" start="00:18:29.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Then we have the rendering pipeline""" start="00:18:31.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which has the MuPDF system package""" start="00:18:33.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""dynamically linked.""" start="00:18:35.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So when you load Emacs Reader,""" start="00:18:38.460" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we initialize a thread pool with eight threads.""" start="00:18:40.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now what you do is let's say we are at page 50.""" start="00:18:45.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""At page 50, the Emacs Reader""" start="00:18:48.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""maintains a cache.""" start="00:18:51.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's like a stack of pages""" start="00:18:54.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that we keep in memory all the time.""" start="00:18:56.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This cache is entirely outside of Emacs.""" start="00:18:58.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It is not inside Emacs environment.""" start="00:19:02.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It is in the C memory heap,""" start="00:19:04.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the MuPDF memory heap""" start="00:19:07.571" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that is outside of Emacs environment.""" start="00:19:09.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It does not make any calls to Emacs anything.""" start="00:19:11.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It does not have a single Elisp line.""" start="00:19:13.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this cache is stored outside.""" start="00:19:15.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now when I want to retrieve""" start="00:19:20.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""anything from this cache,""" start="00:19:22.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""let's say, so I have cached""" start="00:19:23.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""up until 55, from 45 to 55.""" start="00:19:26.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So what happens is that""" start="00:19:29.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""when you're at page 50,""" start="00:19:31.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you always have a cache""" start="00:19:32.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that's n + 5 and n - 5.""" start="00:19:34.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you have cache of 5 pages forward""" start="00:19:36.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and 5 pages backward.""" start="00:19:39.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But let's say I want to go to page 56.""" start="00:19:41.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So I will ask an Emacs render page 56.""" start="00:19:45.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And I'm not going to ask it""" start="00:19:50.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to MuPDF directly.""" start="00:19:51.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm going to ask it""" start="00:19:53.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to the thread pool that do this job.""" start="00:19:54.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And thread pool is going to""" start="00:19:56.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""assign one thread to it.""" start="00:19:58.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Let's say the thread 1""" start="00:19:59.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which is going to render page 56.""" start="00:20:00.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So this thread is going to make calls to MuPDF""" start="00:20:03.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""through our code dynamic module.""" start="00:20:06.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And MuPDF after rendering it""" start="00:20:08.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is going to store it in the cache.""" start="00:20:11.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we're going to add another 56 page to this.""" start="00:20:13.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now, while this is happening,""" start="00:20:18.060" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs Reader does not, like Emacs itself,""" start="00:20:21.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the session is not going to be stuck""" start="00:20:24.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because we just made a call to the thread.""" start="00:20:27.380" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We just asked the thread.""" start="00:20:30.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So like this, this call, like it's done.""" start="00:20:32.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you just assign something to a thread""" start="00:20:35.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then this is fine.""" start="00:20:38.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Like, you're not waiting for the thread""" start="00:20:40.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to complete or anything.""" start="00:20:42.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs is not waiting for the thread to complete.""" start="00:20:43.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The dynamic module or the C side""" start="00:20:46.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""might wait to complete""" start="00:20:48.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but that is entirely different from""" start="00:20:49.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the Emacs session.""" start="00:20:51.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So Emacs viewer can continue to""" start="00:20:52.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""display the page 50""" start="00:20:54.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""while the rendering pipeline""" start="00:20:56.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is still rendering the 56th page.""" start="00:20:58.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And when Emacs asks to display page 56,""" start="00:21:01.980" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it's going to ask it to a thread pool.""" start="00:21:05.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Then thread pool is going to assign""" start="00:21:09.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""another thread, let's say this one,""" start="00:21:11.537" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to retrieve page 56 from the memory cache.""" start="00:21:13.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And then the 56 page is going to be sent""" start="00:21:17.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to the Emacs to be displayed.""" start="00:21:20.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Again, the retrieval part""" start="00:21:24.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is entirely independent of Emacs.""" start="00:21:26.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs does not have to wait for it.""" start="00:21:28.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs only needs to wait to display it.""" start="00:21:30.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, the displaying part""" start="00:21:34.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and the rendering pipeline""" start="00:21:36.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""are entirely asynchronous, so to speak.""" start="00:21:37.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And in the diagram, if you see,""" start="00:21:41.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""all the arrows that are""" start="00:21:43.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""magenta in color,""" start="00:21:46.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""they are native to the Emacs runtime.""" start="00:21:48.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That is, they are single-threaded.""" start="00:21:51.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They are connected to Emacs.""" start="00:21:53.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And all the arrows that are red in color,""" start="00:21:55.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""they are totally asynchronous.""" start="00:21:58.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They can be multi-threaded if you want.""" start="00:22:01.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They are multi-threaded by default""" start="00:22:03.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because they interact""" start="00:22:05.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""only with the MuPDF shared library""" start="00:22:07.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and the C heap.""" start="00:22:09.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They do not touch anything""" start="00:22:11.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the Emacs runtime.""" start="00:22:12.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is how we're able to switch quickly""" start="00:22:14.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""between these huge scanned PDFs""" start="00:22:18.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that have huge images""" start="00:22:22.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in each of their pages""" start="00:22:23.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because we don't really wait for""" start="00:22:25.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""each page to be rendered.""" start="00:22:28.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And Emacs does not wait for that.""" start="00:22:31.380" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's another architectural feature""" start="00:22:35.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of Emacs Reader""" start="00:22:39.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that we are system-level multithreaded.""" start="00:22:40.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now Emacs viewer also supports""" start="00:22:43.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""almost all document formats.""" start="00:22:47.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It supports PDF, EPUB, MOBI, XPS, CPZ comics,""" start="00:22:49.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it even supports""" start="00:22:54.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""other non-ebook formats""" start="00:22:56.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""like document format,""" start="00:22:59.971" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so you can open""" start="00:23:00.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""LibreOffice documents in it,""" start="00:23:01.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and even stuff like PPT and Excel in it,""" start="00:23:04.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""even though they're not going to be""" start="00:23:07.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""supported in a as nice manner.""" start="00:23:08.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And we can do that because MuPDF does this.""" start="00:23:13.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""MuPDF has support for all of this""" start="00:23:16.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it treats them just as it treats PDF.""" start="00:23:18.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Nothing special.""" start="00:23:22.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The only thing that we don't support right now""" start="00:23:24.540" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is DejaVu, so that is not supported right now.""" start="00:23:26.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm going to work on making it supported""" start="00:23:30.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""at the upstream MuPDF.""" start="00:23:33.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's going to take a long time,""" start="00:23:36.020" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but it's in the plans.""" start="00:23:38.440" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Native Emacs integrations""" start="00:23:44.240" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Now with Emacs Reader,""" start="00:23:44.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we also integrate""" start="00:23:45.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""with existing Emacs packages""" start="00:23:46.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as much as possible.""" start="00:23:48.620" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So bookmarks, C-x r b,""" start="00:23:50.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you can do it natively.""" start="00:23:53.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you can save a page as a bookmark""" start="00:23:54.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just as you save anything else in Emacs""" start="00:23:57.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as a bookmark.""" start="00:23:59.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""There's also saveplace integration.""" start="00:24:00.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you can scroll a PDF, close it,""" start="00:24:02.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then come back to it""" start="00:24:06.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""at the same page that you saved it at.""" start="00:24:07.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Sorry, that you closed it at.""" start="00:24:10.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And it's going to work just out of the box""" start="00:24:12.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because of the saveplace""" start="00:24:14.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""package in Emacs that is built in.""" start="00:24:16.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We also have imenu integration""" start="00:24:19.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for table of contents.""" start="00:24:20.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if you see this, this is imenu""" start="00:24:22.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and you can scroll through the contents""" start="00:24:26.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just like you scroll through any imenu.""" start="00:24:28.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can also do it in the menu bar by clicking.""" start="00:24:30.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It works just as nice.""" start="00:24:39.500" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We also have something like""" start="00:24:40.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the outline mode that pdf-tools has.""" start="00:24:42.740" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So if you press O in a document,""" start="00:24:44.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it's going to give you this outline.""" start="00:24:48.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And these are buttons that are clickable.""" start="00:24:49.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can click them.""" start="00:24:53.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can press Enter at them.""" start="00:24:54.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And this is the menu bar item that I was looking at.""" start="00:24:56.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If you click here, index,""" start="00:25:00.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it's going to show you""" start="00:25:02.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the exact same thing""" start="00:25:03.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but in a different interface.""" start="00:25:05.340" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""(Naive) dark mode""" start="00:25:10.340" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""We also have a naive dark mode,""" start="00:25:10.340" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which is not really as nice as""" start="00:25:15.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we would like it to be,""" start="00:25:17.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and dark mode fanatics""" start="00:25:18.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I'm sure will have issues with it,""" start="00:25:20.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but we're going to improve it in time.""" start="00:25:22.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""For now, this is what we have.""" start="00:25:24.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And it can be enabled per document,""" start="00:25:27.380" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so you can have one, like,""" start="00:25:30.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""one document that is in dark mode,""" start="00:25:33.100" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but another one that is not.""" start="00:25:34.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That is nice to have.""" start="00:25:36.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Eventually we're going to work on more themes.""" start="00:25:39.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You should be able to actually integrate it""" start="00:25:42.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""with Emacs themes as much as possible.""" start="00:25:46.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can make it default so that""" start="00:25:49.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it inherits colors from the Emacs theme.""" start="00:25:52.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That is one of the things""" start="00:25:54.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that we also have planned.""" start="00:25:56.360" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Challenges and further improvements""" start="00:26:01.140" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""We did face a bunch of challenges""" start="00:26:01.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""while trying to implement these features.""" start="00:26:03.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""One of the initial challenges was that""" start="00:26:05.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""SVGs were actually a bad idea.""" start="00:26:07.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""They're huge, especially in scanned PDFs,""" start="00:26:09.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and they make things much slower.""" start="00:26:12.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we chose to actually have PPMs,""" start="00:26:14.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which is the simplest image format ever possible.""" start="00:26:18.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Now, it was also very difficult""" start="00:26:24.100" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to make reader-mode be window-specific.""" start="00:26:26.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So, you know, while you're scrolling""" start="00:26:29.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the same document in one window,""" start="00:26:31.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the other window with the same document""" start="00:26:34.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""should not change.""" start="00:26:36.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We should be able to have multiple pages""" start="00:26:37.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in different windows of the same document.""" start="00:26:39.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That was very difficult""" start="00:26:42.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because as I told you about the cache,""" start="00:26:44.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the cache works in an idiosyncratic manner""" start="00:26:46.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and we needed to make it so that each window""" start="00:26:50.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""will have its own cache""" start="00:26:54.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""instead of having a global cache for each file.""" start="00:26:56.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That took some rewrite.""" start="00:27:01.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And now, because we needed to do""" start="00:27:03.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""this sort of multithreading,""" start="00:27:06.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""system-level multithreading,""" start="00:27:07.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we needed to use""" start="00:27:09.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a specific package of MuPDF""" start="00:27:10.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that had a bug for this which got fixed.""" start="00:27:13.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And that's 1.26.0.""" start="00:27:16.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Because we did that,""" start="00:27:20.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a lot of the GNU/Linux distributions did not""" start="00:27:23.337" video="mainVideo-reader" id="subtitle"]] +[[!template text="""really have this latest package.""" start="00:27:26.463" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we had to actually""" start="00:27:28.872" video="mainVideo-reader" id="subtitle"]] +[[!template text="""package it in-tree.""" start="00:27:30.772" video="mainVideo-reader" id="subtitle"]] +[[!template text="""as a git sub-module.""" start="00:27:33.805" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That was a horror! But eventually... now""" start="00:27:36.972" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I think most GNU/Linux distributions""" start="00:27:40.738" video="mainVideo-reader" id="subtitle"]] +[[!template text="""already have this [version].""" start="00:27:43.605" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The upcoming features that we have planned""" start="00:27:46.341" video="mainVideo-reader" id="subtitle"]] +[[!template text="""are the first one is that we need to rewrite""" start="00:27:48.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the display mechanism entirely from scratch""" start="00:27:52.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to use a tiled rendering approach.""" start="00:27:55.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So right now we just take an image""" start="00:27:57.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and display it inside an Emacs buffer""" start="00:28:00.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""just like that.""" start="00:28:02.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""But it will be changed so that the image""" start="00:28:03.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""will be displayed in the tiled manner""" start="00:28:08.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so there will be multiple tiles""" start="00:28:10.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but it'll be pixel perfect""" start="00:28:12.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so you won't really see a difference.""" start="00:28:14.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The reason to do this is to implement features""" start="00:28:16.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for text selection, actually.""" start="00:28:19.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we can't really do text selection""" start="00:28:21.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""without running into a bunch of memory""" start="00:28:24.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and other issues latency issues""" start="00:28:27.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""if we don't do tiling.""" start="00:28:30.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So we need to do those two things,""" start="00:28:33.020" video="mainVideo-reader" id="subtitle"]] +[[!template text="""they are at the highest priority right now.""" start="00:28:35.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And then, once we're done with that,""" start="00:28:38.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we're going to support annotations,""" start="00:28:40.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""highlighting, everything that you're used to""" start="00:28:42.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in pdf-tools and org-noter.""" start="00:28:45.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And once we're done with that,""" start="00:28:47.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we're going to also integrate with AucTeX and SyncTeX.""" start="00:28:50.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Because right now, when a PDF gets updated,""" start="00:28:55.020" video="mainVideo-reader" id="subtitle"]] +[[!template text="""especially a LaTeX PDF,""" start="00:28:58.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""since there is no SyncTeX integration,""" start="00:29:00.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it can't really do it nicely""" start="00:29:03.438" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it sometimes even crashes Emacs.""" start="00:29:05.772" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's something that""" start="00:29:08.661" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we will be planning to implement.""" start="00:29:11.538" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""What Emacs can learn?""" start="00:29:14.272" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Now, from this experiment,""" start="00:29:14.272" video="mainVideo-reader" id="subtitle"]] +[[!template text="""what exactly can Emacs,""" start="00:29:16.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the Emacs core devs and others""" start="00:29:17.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who are building packages can learn?""" start="00:29:20.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Well, the first thing is that all of this""" start="00:29:22.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""should not be really this difficult""" start="00:29:24.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because all we're asking from Emacs""" start="00:29:27.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is to display images in real-time""" start="00:29:30.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and update them in real-time.""" start="00:29:32.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That should not be that difficult""" start="00:29:36.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of a thing to do, but apparently it is.""" start="00:29:37.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And that's why Emacs's graphical interface""" start="00:29:40.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""needs to be more modular, more composable,""" start="00:29:43.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and flexible for real-time graphics.""" start="00:29:47.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""If it is supposed to have things like,""" start="00:29:51.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""again, a document reader,""" start="00:29:54.220" video="mainVideo-reader" id="subtitle"]] +[[!template text="""something like a video editor,""" start="00:29:56.180" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and something like that,""" start="00:29:57.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs's graphical interface""" start="00:29:58.980" video="mainVideo-reader" id="subtitle"]] +[[!template text="""needs to grow and be more mature.""" start="00:30:00.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""One of the things""" start="00:30:05.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that's stopping it from doing that""" start="00:30:06.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is actually Emacs's overlay functionality.""" start="00:30:08.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So right now, the way we display""" start="00:30:10.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""an image in a buffer""" start="00:30:13.940" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is using an overlay,""" start="00:30:16.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""actually multiple overlays.""" start="00:30:18.901" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Overlays are static in the sense that""" start="00:30:22.020" video="mainVideo-reader" id="subtitle"]] +[[!template text="""if I attach to one image to one overlay,""" start="00:30:25.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I need to have an entirely different image""" start="00:30:29.740" video="mainVideo-reader" id="subtitle"]] +[[!template text="""updated for that overlay.""" start="00:30:34.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So I need to create another different image,""" start="00:30:37.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""change it in the memory,""" start="00:30:39.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and then display it to update it.""" start="00:30:41.180" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I can't change the image data""" start="00:30:43.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in real time of the overlay.""" start="00:30:46.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And that is a big issue.""" start="00:30:49.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I've actually made an emacs-devel""" start="00:30:54.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""mailing list thread about it.""" start="00:30:56.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I talked to Eli about it as well.""" start="00:30:58.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And he said there's a possibility""" start="00:31:01.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that this can be changed,""" start="00:31:04.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but it's going to take""" start="00:31:05.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a certain amount of rewrite.""" start="00:31:06.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""There's also issues with Emacs GC.""" start="00:31:09.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs GC sometimes leaks memory""" start="00:31:12.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""when you update images too quickly.""" start="00:31:14.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That is, when you have a bunch of images""" start="00:31:16.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that are getting churned out too quickly,""" start="00:31:18.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs GC starts leaking""" start="00:31:21.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and it just goes up to""" start="00:31:23.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""a huge number of gigabytes in RAM.""" start="00:31:25.160" video="mainVideo-reader" id="subtitle"]] +[[!template text="""That's also a huge problem.""" start="00:31:29.680" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The dynamic module API,""" start="00:31:32.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the emacs-module.h header,""" start="00:31:33.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""needs to have more helpers.""" start="00:31:37.140" video="mainVideo-reader" id="subtitle"]] +[[!template text="""It's really bare bones,""" start="00:31:38.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and I like that it is bare bones""" start="00:31:41.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so that other languages can use it,""" start="00:31:43.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""but at the same time, I think""" start="00:31:45.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""it'll be really good""" start="00:31:46.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""if we can have some helpers""" start="00:31:47.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that can do better memory interaction,""" start="00:31:49.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""like strings and so on,""" start="00:31:53.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""which we also faced some issues with.""" start="00:31:57.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Emacs's fractional scaling system""" start="00:32:00.380" video="mainVideo-reader" id="subtitle"]] +[[!template text="""seems to be broken across different toolkits.""" start="00:32:02.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We have bug reports that say in pgtk in Wayland,""" start="00:32:05.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""something seems to render differently""" start="00:32:11.000" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because they have fractional scaling enabled.""" start="00:32:13.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So that's something""" start="00:32:17.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""that I think Emacs, overall,""" start="00:32:18.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I think Emacs needs to focus on improving""" start="00:32:21.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""the graphical interface pipeline""" start="00:32:24.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to be a much more mature one.""" start="00:32:28.240" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Contributing to the development""" start="00:32:32.300" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""And finally, how can you contribute""" start="00:32:32.300" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to the development of Emacs Reader?""" start="00:32:34.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Well, we are on Codeberg.""" start="00:32:35.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""We are not on GitHub, sorry.""" start="00:32:37.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can go there,""" start="00:32:40.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you can look through the issues""" start="00:32:41.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and send us a PR if you're interested.""" start="00:32:43.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""The next major release""" start="00:32:45.280" video="mainVideo-reader" id="subtitle"]] +[[!template text="""is going to go to GNU ELPA.""" start="00:32:46.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Finally, we are not yet at GNU ELPA,""" start="00:32:49.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so you can't really do M-x package-install""" start="00:32:52.260" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and install our package.""" start="00:32:54.440" video="mainVideo-reader" id="subtitle"]] +[[!template text="""you would need to install it""" start="00:32:56.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""through use-package-:vc.""" start="00:32:58.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And since we're going to go to GNU ELPA,""" start="00:33:04.940" video="mainVideo-reader" id="subtitle"]] +[[!template text="""we request you to assign""" start="00:33:07.500" video="mainVideo-reader" id="subtitle"]] +[[!template text="""your copyright to Emacs""" start="00:33:09.120" video="mainVideo-reader" id="subtitle"]] +[[!template text="""because GNU ELPA is essentially part of GNU Emacs.""" start="00:33:10.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So you would need to do copyright assignment""" start="00:33:13.960" video="mainVideo-reader" id="subtitle"]] +[[!template text="""if you make non-trivial contribution.""" start="00:33:16.720" video="mainVideo-reader" id="subtitle"]] +[[!template text="""You can join us at IRC""" start="00:33:20.580" video="mainVideo-reader" id="subtitle"]] +[[!template text="""at #phi-mu-lambda.""" start="00:33:22.480" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And I also stream the development""" start="00:33:24.360" video="mainVideo-reader" id="subtitle"]] +[[!template text="""of this package""" start="00:33:27.200" video="mainVideo-reader" id="subtitle"]] +[[!template text="""bi-weekly on Sundays""" start="00:33:28.040" video="mainVideo-reader" id="subtitle"]] +[[!template text="""at PeerTube at the following channel.""" start="00:33:29.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Feel free to join us.""" start="00:33:31.640" video="mainVideo-reader" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Acknowledgements""" start="00:33:35.520" video="mainVideo-reader" id="subtitle"]]</div>[[!template text="""Finally, I want to thank Tushar,""" start="00:33:35.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who has been persistently contributing""" start="00:33:38.500" video="mainVideo-reader" id="subtitle"]] +[[!template text="""to the project since 0.1.0,""" start="00:33:40.640" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and I'm very, very thankful for him,""" start="00:33:42.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""for his suggestions,""" start="00:33:46.520" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and for his code contributions as well.""" start="00:33:47.760" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I would also like to thank Prom,""" start="00:33:50.880" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who fixed a major bug""" start="00:33:53.320" video="mainVideo-reader" id="subtitle"]] +[[!template text="""in the Windows build,""" start="00:33:55.800" video="mainVideo-reader" id="subtitle"]] +[[!template text="""since I don't really use Windows anymore,""" start="00:33:56.860" video="mainVideo-reader" id="subtitle"]] +[[!template text="""so that was really nice,""" start="00:33:58.840" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and for Teeoius, for fixing a pthread bug.""" start="00:33:59.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""I would also like to thank others""" start="00:34:05.460" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who helped fix little things,""" start="00:34:06.920" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who come to the stream to chat,""" start="00:34:09.560" video="mainVideo-reader" id="subtitle"]] +[[!template text="""who sort of see me bang my head""" start="00:34:13.180" video="mainVideo-reader" id="subtitle"]] +[[!template text="""across these C memory bugs.""" start="00:34:16.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""So thank you to all of those.""" start="00:34:19.240" video="mainVideo-reader" id="subtitle"]] +[[!template text="""And thank you finally to the viewers""" start="00:34:21.600" video="mainVideo-reader" id="subtitle"]] +[[!template text="""and to EmacsConf organizers as well.""" start="00:34:24.400" video="mainVideo-reader" id="subtitle"]] +[[!template text="""This is a splendid opportunity.""" start="00:34:28.080" video="mainVideo-reader" id="subtitle"]] +[[!template text="""Thank you.""" start="00:34:31.940" video="mainVideo-reader" id="subtitle"]] + +</div> + +Captioner: jay_bird + Questions or comments? Please e-mail [divya@subvertising.org](mailto:divya@subvertising.org?subject=Comment%20for%20EmacsConf%202023%20reader%3A%20An%20introduction%20to%20the%20Emacs%20Reader) diff --git a/2025/info/reader-before.md b/2025/info/reader-before.md index e2036a3a..47837784 100644 --- a/2025/info/reader-before.md +++ b/2025/info/reader-before.md @@ -8,12 +8,12 @@ The following image shows where the talk is in the schedule for Sun 2025-12-07. Format: 35-min talk ; Q&A: BigBlueButton conference room <https://media.emacsconf.org/2025/current/bbb-reader.html> Etherpad: <https://pad.emacsconf.org/2025-reader> Etherpad: <https://pad.emacsconf.org/2025-reader> Discuss on IRC: [#emacsconf-gen](https://chat.emacsconf.org/?join=emacsconf,emacsconf-gen) -Status: Processing uploaded video +Status: Now playing on the conference livestream <div>Times in different time zones:</div><div class="times" start="2025-12-07T14:40:00Z" end="2025-12-07T15:15:00Z"><div class="conf-time">Sunday, Dec 7 2025, ~9:40 AM - 10:15 AM EST (US/Eastern)</div><div class="others"><div>which is the same as:</div>Sunday, Dec 7 2025, ~8:40 AM - 9:15 AM CST (US/Central)<br />Sunday, Dec 7 2025, ~7:40 AM - 8:15 AM MST (US/Mountain)<br />Sunday, Dec 7 2025, ~6:40 AM - 7:15 AM PST (US/Pacific)<br />Sunday, Dec 7 2025, ~2:40 PM - 3:15 PM UTC <br />Sunday, Dec 7 2025, ~3:40 PM - 4:15 PM CET (Europe/Paris)<br />Sunday, Dec 7 2025, ~4:40 PM - 5:15 PM EET (Europe/Athens)<br />Sunday, Dec 7 2025, ~8:10 PM - 8:45 PM IST (Asia/Kolkata)<br />Sunday, Dec 7 2025, ~10:40 PM - 11:15 PM +08 (Asia/Singapore)<br />Sunday, Dec 7 2025, ~11:40 PM - 12:15 AM JST (Asia/Tokyo)</div></div><div><strong><a href="/2025/watch/gen/">Find out how to watch and participate</a></strong></div> - +<div class="vid mainVideo"><video controls preload="none" id="mainVideo-reader"><source src="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.webm" />captions="""<track label="English" kind="captions" srclang="en" src="/2025/captions/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt" default />"""<p><em>Your browser does not support the video tag. Please download the video instead.</em></p></video><div></div>Duration: 34:37 minutes<div class="files resources"><ul><li><a href="https://pad.emacsconf.org/2025-reader">Open Etherpad</a></li><li><a href="https://media.emacsconf.org/2025/current/bbb-reader.html">Open public Q&A</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--intro.vtt">Download --intro.vtt</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--intro.webm">Download --intro.webm</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.opus">Download --main.opus (30MB)</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.png">Download --main.png</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.vtt">Download --main.vtt</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-reader--an-introduction-to-the-emacs-reader--divy--main.webm">Download --main.webm (101MB)</a></li></ul></div></div> # Description <!-- End of emacsconf-publish-before-page -->
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