load twemoji dynamically as colr or sbix; fix monospace

2019-05-22 02:31:24 +01:00 · 2019-05-22 02:31:24 +01:00 · 4ae652e5c3
commit 4ae652e5c3
parent 8b9017891b
7 changed files with 117 additions and 14 deletions
--- a/src/utils/FontManager.js
+++ b/src/utils/FontManager.js
@ -0,0 +1,78 @@
+/*
+Copyright 2019 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+/*
+ * Based on...
+ * ChromaCheck 1.16
+ * author Roel Nieskens, https://pixelambacht.nl
+ * MIT license
+ */
+
+let colrFontSupported = undefined;
+
+async function isColrFontSupported() {
+    if (colrFontSupported !== undefined) {
+        return colrFontSupported;
+    }
+
+    try {
+        let canvas = document.createElement('canvas');
+        let context = canvas.getContext('2d');
+        let img = new Image();
+        let fontCOLR = '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';
+        let svg = '<svg xmlns="http://www.w3.org/2000/svg" width="20" height="100" style="background:#fff;fill:#000;">' +
+                      '<style type="text/css">'+
+                          '@font-face{font-family:"chromacheck-colr";src:url(data:application/x-font-woff;base64,'+fontCOLR+') format("woff");}'+
+                      '</style>'+
+                      '<text x="0" y="0" font-size="20">' +
+                          '<tspan font-family="chromacheck-colr" x="0" dy="20">&#xe900;</tspan>' + // COLR
+                      '</text>' +
+                  '</svg>';
+        canvas.width  = 20;
+        canvas.height = 100;
+
+        img.src = 'data:image/svg+xml;charset=utf-8,' + encodeURIComponent(svg);
+
+        // FIXME wait for safari load our colr font
+        const wait = ms => new Promise((r, j)=>setTimeout(r, ms))
+        await wait(500);
+
+        context.drawImage(img, 0, 0);
+        colrFontSupported = (context.getImageData(10, 10, 1, 1).data[0] === 200);
+    }
+    catch (e) {
+        console.error("Couldn't load colr font", e);
+        colrFontSupported = false;
+    }
+    return colrFontSupported;
+}
+
+export async function fixupColorFonts() {
+    if (colrFontSupported !== undefined) {
+        return;
+    }
+
+    // we programatically add the right fontface.
+    let font;
+    if (await isColrFontSupported()) {
+        font = new FontFace("Twemoji", "url('../../fonts/Twemoji_Mozilla/TwemojiMozilla-colr.woff2')", {});
+    }
+    else {
+        font = new FontFace("Twemoji", "url('../../fonts/Twemoji_Mozilla/TwemojiMozilla-sbix.woff2')", {});
+    }
+    document.fonts.add(font);
+}
+