Merge pull request #50 from dmitrylyzo/WeebDataHoarder/lazy-fonts

[WeebDataHoarder] Implement lazy font loading + customizable fallback font

Makefile

@@ -155,16 +155,16 @@ all-src:
 EMCC_COMMON_ARGS = \
 	$(LDFLAGS) \
 	-s EXPORTED_FUNCTIONS="['_main', '_malloc']" \
+	-s DEFAULT_LIBRARY_FUNCS_TO_INCLUDE="['\$$Browser']" \
 	-s EXPORTED_RUNTIME_METHODS="['ccall', 'cwrap', 'getValue', 'FS_createPreloadedFile', 'FS_createPath']" \
-	--use-preload-plugins \
-	--preload-file assets/default.woff2 \
-	--preload-file assets/fonts.conf \
+	--embed-file assets/fonts.conf \
 	-s ALLOW_MEMORY_GROWTH=1 \
 	-s NO_FILESYSTEM=0 \
+	--memory-init-file=0 \
 	--no-heap-copy \
 	-o $@
 
-dist: src/subtitles-octopus-worker.bc dist/js/subtitles-octopus-worker.js dist/js/subtitles-octopus-worker-legacy.js dist/js/subtitles-octopus.js dist/js/COPYRIGHT
+dist: src/subtitles-octopus-worker.bc dist/js/subtitles-octopus-worker.js dist/js/subtitles-octopus-worker-legacy.js dist/js/subtitles-octopus.js dist/js/COPYRIGHT dist/js/default.woff2
 
 dist/js/subtitles-octopus-worker.js: src/subtitles-octopus-worker.bc src/pre-worker.js src/SubOctpInterface.js src/post-worker.js build/lib/brotli/js/decode.js
 	mkdir -p dist/js
@@ -202,6 +202,9 @@ dist/license/all:
 dist/js/COPYRIGHT: dist/license/all
 	cp "$<" "$@"
 
+dist/js/default.woff2:
+	cp assets/default.woff2 "$@"
+
 # Clean Tasks
 
 clean: clean-dist clean-libs clean-octopus

README.md

@@ -114,6 +114,8 @@ When creating an instance of SubtitleOctopus, you can set the following options:
 - `fonts`: An array of links to the fonts used in the subtitle. (Optional)
 - `availableFonts`: Object with all available fonts - Key is font name in lower
   case, value is link: `{"arial": "/font1.ttf"}` (Optional)
+- `fallbackFont`: URL to override fallback font, for example, with a CJK one. Default fallback font is Liberation Sans (Optional)
+- `lazyFileLoading`: A boolean, whether to load files in a lazy way via [FS.createLazyFile()](https://emscripten.org/docs/api_reference/Filesystem-API.html#FS.createLazyFile). [Requires](https://github.com/emscripten-core/emscripten/blob/c7b21c32fef92799da05d15ba1939b6394fe0373/src/library_fs.js#L1679-L1856) `Access-Control-Expose-Headers` for `Accept-Ranges, Content-Length, and Content-Encoding`. If encoding is compressed or length is not set, file will be fully fetched instead of just a HEAD request.
 - `timeOffset`: The amount of time the subtitles should be offset from the
   video. (Default: `0`)
 - `onReady`: Function that's called when SubtitlesOctopus is ready. (Optional)

src/SubtitleOctopus.cpp

@@ -6,6 +6,7 @@
 #include <stdlib.h>
 #include <stdarg.h>
 #include <string.h>
+#include <string>
 #include <ass/ass.h>
 
 #include "libass.cpp"
@@ -294,6 +295,8 @@ class SubtitleOctopus {
 
     int status;
 
+    std::string defaultFont;
+
     SubtitleOctopus(): ass_library(NULL), ass_renderer(NULL), track(NULL), canvas_w(0), canvas_h(0), status(0), m_is_event_animated(NULL), m_drop_animations(false) {
     }
 
@@ -311,7 +314,11 @@ class SubtitleOctopus {
         return m_drop_animations;
     }
 
-    void initLibrary(int frame_w, int frame_h) {
+    void initLibrary(int frame_w, int frame_h, char* default_font) {
+        if (default_font != NULL) {
+            defaultFont.assign(default_font);
+        }
+
         ass_library = ass_library_init();
         if (!ass_library) {
             fprintf(stderr, "jso: ass_library_init failed!\n");
@@ -390,11 +397,11 @@ class SubtitleOctopus {
     void reloadLibrary() {
         quitLibrary();
 
-        initLibrary(canvas_w, canvas_h);
+        initLibrary(canvas_w, canvas_h, NULL);
     }
 
     void reloadFonts() {
-        ass_set_fonts(ass_renderer, "/assets/default.woff2", NULL, ASS_FONTPROVIDER_FONTCONFIG, "/assets/fonts.conf", 1);
+        ass_set_fonts(ass_renderer, defaultFont.c_str(), NULL, ASS_FONTPROVIDER_FONTCONFIG, "/assets/fonts.conf", 1);
     }
 
     void setMargin(int top, int bottom, int left, int right) {

src/SubtitleOctopus.idl

@@ -186,7 +186,7 @@ interface SubtitleOctopus {
     void setLogLevel(long level);
     void setDropAnimations(long value);
     long getDropAnimations();
-    void initLibrary(long frame_w, long frame_h);
+    void initLibrary(long frame_w, long frame_h, DOMString default_font);
     void createTrack(DOMString subfile);
     void createTrackMem(DOMString buf, unsigned long bufsize);
     void removeTrack();

src/post-worker.js

@@ -33,13 +33,18 @@ self.writeFontToFS = function(font) {
     self.fontMap_[font] = true;
 
     if (!self.availableFonts.hasOwnProperty(font)) return;
-    var content = readBinary(self.availableFonts[font]);
 
-    Module["FS"].writeFile('/fonts/font' + (self.fontId++) + '-' + self.availableFonts[font].split('/').pop(), content, {
-        encoding: 'binary'
-    });
+    self.loadFontFile('font' + (self.fontId++) + '-', self.availableFonts[font]);
 };
 
+self.loadFontFile = function (fontId, path) {
+    if (self.lazyFileLoading && path.indexOf("blob:") !== 0) {
+        Module["FS"].createLazyFile("/fonts", fontId + path.split('/').pop(), path, true, false);
+    } else {
+        Module["FS"].createPreloadedFile("/fonts", fontId + path.split('/').pop(), path, true, false);
+    }
+}
+
 /**
  * Write all font's mentioned in the .ass file to the virtual FS.
  * @param {!string} content the file content.
@@ -611,6 +616,8 @@ function onMessageFromMainEmscriptenThread(message) {
             }
 
             self.availableFonts = message.data.availableFonts;
+            self.fallbackFont = message.data.fallbackFont;
+            self.lazyFileLoading = message.data.lazyFileLoading;
             self.debug = message.data.debug;
             if (!hasNativeConsole && self.debug) {
                 console = makeCustomConsole();

src/pre-worker.js

@@ -88,10 +88,12 @@ Module["preRun"].push(function () {
 
     self.subContent = null;
 
+    self.loadFontFile(".fallback-", self.fallbackFont);
+
     //Module["FS"].mount(Module["FS"].filesystems.IDBFS, {}, '/fonts');
     var fontFiles = self.fontFiles || [];
     for (var i = 0; i < fontFiles.length; i++) {
-        Module["FS_createPreloadedFile"]("/fonts", 'font' + i + '-' + fontFiles[i].split('/').pop(), fontFiles[i], true, true);
+        self.loadFontFile('font' + i + '-', fontFiles[i]);
     }
 });
 
@@ -100,7 +102,7 @@ Module['onRuntimeInitialized'] = function () {
 
     self.changed = Module._malloc(4);
 
-    self.octObj.initLibrary(screen.width, screen.height);
+    self.octObj.initLibrary(screen.width, screen.height, "/fonts/.fallback-" + self.fallbackFont.split('/').pop());
     self.octObj.setDropAnimations(!!self.dropAllAnimations);
     self.octObj.createTrack("/sub.ass");
     self.ass_track = self.octObj.track;

src/subtitles-octopus.js

@@ -35,6 +35,8 @@ var SubtitlesOctopus = function (options) {
     self.canvasParent = null; // (internal) HTML canvas parent element
     self.fonts = options.fonts || []; // Array with links to fonts used in sub (optional)
     self.availableFonts = options.availableFonts || []; // Object with all available fonts (optional). Key is font name in lower case, value is link: {"arial": "/font1.ttf"}
+    self.fallbackFont = options.fallbackFont || 'default.woff2'; // URL to override fallback font, for example, with a CJK one. Default fallback font is Liberation Sans (Optional)
+    self.lazyFileLoading = options.lazyFileLoading || false; // Load fonts in a lazy way. Requires Access-Control-Expose-Headers for Accept-Ranges, Content-Length, and Content-Encoding. If Content-Encoding is compressed, file will be fully fetched instead of just a HEAD request.
     self.onReadyEvent = options.onReady; // Function called when SubtitlesOctopus is ready (optional)
     if (supportsWebAssembly) {
         self.workerUrl = options.workerUrl || 'subtitles-octopus-worker.js'; // Link to WebAssembly worker
@@ -144,6 +146,8 @@ var SubtitlesOctopus = function (options) {
             subContent: self.subContent,
             fonts: self.fonts,
             availableFonts: self.availableFonts,
+            fallbackFont: self.fallbackFont,
+            lazyFileLoading: self.lazyFileLoading,
             debug: self.debug,
             targetFps: self.targetFps,
             libassMemoryLimit: self.libassMemoryLimit,