Canvas-based TextBubbleSkin

src/Drawable.js

@@ -329,6 +329,11 @@ class Drawable {
             scaledSize[1] = skinSize[1] * this._scale[1] / 100;
             // scaledSize[2] = 0;
 
+            if (this.skin.roundBounds) {
+                scaledSize[0] = Math.ceil(scaledSize[0]);
+                scaledSize[1] = Math.ceil(scaledSize[1]);
+            }
+
             this._skinScaleDirty = false;
         }
 

src/RenderWebGL.js

@@ -10,7 +10,7 @@ const PenSkin = require('./PenSkin');
 const RenderConstants = require('./RenderConstants');
 const ShaderManager = require('./ShaderManager');
 const SVGSkin = require('./SVGSkin');
-const SVGTextBubble = require('./util/svg-text-bubble');
+const TextBubbleSkin = require('./TextBubbleSkin');
 const EffectTransform = require('./EffectTransform');
 const log = require('./util/log');
 
@@ -184,8 +184,6 @@ class RenderWebGL extends EventEmitter {
         /** @type {Array.<snapshotCallback>} */
         this._snapshotCallbacks = [];
 
-        this._svgTextBubble = new SVGTextBubble();
-
         this._createGeometry();
 
         this.on(RenderConstants.Events.NativeSizeChanged, this.onNativeSizeChanged);
@@ -343,8 +341,11 @@ class RenderWebGL extends EventEmitter {
      * @returns {!int} the ID for the new skin.
      */
     createTextSkin (type, text, pointsLeft) {
-        const bubbleSvg = this._svgTextBubble.buildString(type, text, pointsLeft);
+        const skinId = this._nextSkinId++;
-        return this.createSVGSkin(bubbleSvg, [0, 0]);
+        const newSkin = new TextBubbleSkin(skinId, this);
+        newSkin.setTextBubble(type, text, pointsLeft);
+        this._allSkins[skinId] = newSkin;
+        return skinId;
     }
 
     /**
@@ -407,8 +408,14 @@ class RenderWebGL extends EventEmitter {
      * @param {!boolean} pointsLeft - which side the bubble is pointing.
      */
     updateTextSkin (skinId, type, text, pointsLeft) {
-        const bubbleSvg = this._svgTextBubble.buildString(type, text, pointsLeft);
+        if (this._allSkins[skinId] instanceof TextBubbleSkin) {
-        this.updateSVGSkin(skinId, bubbleSvg, [0, 0]);
+            this._allSkins[skinId].setTextBubble(type, text, pointsLeft);
+            return;
+        }
+
+        const newSkin = new TextBubbleSkin(skinId, this);
+        newSkin.setTextBubble(type, text, pointsLeft);
+        this._reskin(skinId, newSkin);
     }
 
 

src/Skin.js

@@ -76,6 +76,15 @@ class Skin extends EventEmitter {
         return false;
     }
 
+    /**
+     * @returns {boolean} whether this skin's pixel bounds should be rounded up to the nearest screen-space pixel.
+     * Useful for skins always rendered in screen-space, e.g. text bubbles.
+     */
+
+    get roundBounds () {
+        return false;
+    }
+
     /**
      * @returns {boolean} true if alpha is premultiplied, false otherwise
      */

src/TextBubbleSkin.js

@@ -0,0 +1,296 @@
+const twgl = require('twgl.js');
+
+const TextWrapper = require('./util/text-wrapper');
+const CanvasMeasurementProvider = require('./util/canvas-measurement-provider');
+const Skin = require('./Skin');
+
+const BubbleStyle = {
+    MAX_LINE_WIDTH: 170, // Maximum width, in Scratch pixels, of a single line of text
+
+    MIN_WIDTH: 50, // Minimum width, in Scratch pixels, of a text bubble
+    STROKE_WIDTH: 4, // Thickness of the stroke around the bubble. Only half's visible because it's drawn under the fill
+    PADDING: 10, // Padding around the text area
+    CORNER_RADIUS: 16, // Radius of the rounded corners
+    TAIL_HEIGHT: 12, // Height of the speech bubble's "tail". Probably should be a constant.
+
+    FONT: 'Helvetica', // Font to render the text with
+    FONT_SIZE: 14, // Font size, in Scratch pixels
+    FONT_HEIGHT_RATIO: 0.9, // Height, in Scratch pixels, of the text, as a proportion of the font's size
+    LINE_HEIGHT: 16, // Spacing between each line of text
+
+    COLORS: {
+        BUBBLE_FILL: 'white',
+        BUBBLE_STROKE: 'rgba(0, 0, 0, 0.15)',
+        TEXT_FILL: '#575E75'
+    }
+};
+
+class TextBubbleSkin extends Skin {
+    /**
+     * Create a new text bubble skin.
+     * @param {!int} id - The ID for this Skin.
+     * @param {!RenderWebGL} renderer - The renderer which will use this skin.
+     * @constructor
+     * @extends Skin
+     */
+    constructor (id, renderer) {
+        super(id);
+
+        /** @type {RenderWebGL} */
+        this._renderer = renderer;
+
+        /** @type {HTMLCanvasElement} */
+        this._canvas = document.createElement('canvas');
+
+        /** @type {WebGLTexture} */
+        this._texture = null;
+
+        /** @type {Array<number>} */
+        this._size = [0, 0];
+
+        /** @type {number} */
+        this._renderedScale = 0;
+
+        /** @type {Array<string>} */
+        this._lines = [];
+
+        this._textSize = {width: 0, height: 0};
+        this._textAreaSize = {width: 0, height: 0};
+
+        /** @type {string} */
+        this._bubbleType = '';
+
+        /** @type {boolean} */
+        this._pointsLeft = false;
+
+        /** @type {boolean} */
+        this._textDirty = true;
+
+        /** @type {boolean} */
+        this._textureDirty = true;
+
+        this.measurementProvider = new CanvasMeasurementProvider(this._canvas.getContext('2d'));
+        this.textWrapper = new TextWrapper(this.measurementProvider);
+
+        this._restyleCanvas();
+    }
+    
+    /**
+     * Dispose of this object. Do not use it after calling this method.
+     */
+    dispose () {
+        if (this._texture) {
+            this._renderer.gl.deleteTexture(this._texture);
+            this._texture = null;
+        }
+        this._canvas = null;
+        super.dispose();
+    }
+
+    /**
+     * @returns {boolean} whether this skin's pixel bounds should be rounded up to the nearest screen-space pixel.
+     * Useful for skins always rendered in screen-space, e.g. text bubbles.
+     */
+    get roundBounds () {
+        return true;
+    }
+    
+    /**
+     * @return {Array<number>} the dimensions, in Scratch units, of this skin.
+     */
+    get size () {
+        if (this._textDirty) {
+            this._reflowLines();
+        }
+        return this._size;
+    }
+
+    /**
+     * Set parameters for this text bubble.
+     * @param {!string} type - either "say" or "think".
+     * @param {!string} text - the text for the bubble.
+     * @param {!boolean} pointsLeft - which side the bubble is pointing.
+     */
+    setTextBubble (type, text, pointsLeft) {
+        this._text = text;
+        this._bubbleType = type;
+        this._pointsLeft = pointsLeft;
+
+        this._textDirty = true;
+        this._textureDirty = true;
+        this.emit(Skin.Events.WasAltered);
+    }
+
+    /**
+     * Re-style the canvas after resizing it. This is necessary to ensure proper text measurement.
+     */
+    _restyleCanvas () {
+        this._canvas.getContext('2d').font = `${BubbleStyle.FONT_SIZE}px ${BubbleStyle.FONT}, sans-serif`;
+    }
+
+    /**
+     * Update the array of wrapped lines and the text dimensions.
+     * @param {string} text - The text to wrap.
+     */
+    _reflowLines () {
+        this._lines = this.textWrapper.wrapText(BubbleStyle.MAX_LINE_WIDTH, this._text);
+
+        // Measure width of longest line to avoid extra-wide bubbles
+        let longestLine = 0;
+        for (const line of this._lines) {
+            longestLine = Math.max(longestLine, this.measurementProvider.measureText(line));
+        }
+
+        this._textSize.width = longestLine;
+        this._textSize.height = BubbleStyle.LINE_HEIGHT * this._lines.length;
+
+        // Calculate the canvas-space sizes of the padded text area and full text bubble
+        const paddedWidth = Math.max(this._textSize.width, BubbleStyle.MIN_WIDTH) + (BubbleStyle.PADDING * 2);
+        const paddedHeight = this._textSize.height + (BubbleStyle.PADDING * 2);
+
+        this._textAreaSize.width = paddedWidth;
+        this._textAreaSize.height = paddedHeight;
+
+        this._size[0] = paddedWidth + BubbleStyle.STROKE_WIDTH;
+        this._size[1] = paddedHeight + BubbleStyle.STROKE_WIDTH + BubbleStyle.TAIL_HEIGHT;
+
+        this._textDirty = false;
+    }
+
+    /**
+     * Render this text bubble at a certain scale, using the current parameters, to the canvas.
+     * @param {number} scale The scale to render the bubble at
+     */
+    _renderTextBubble (scale) {
+        const ctx = this._canvas.getContext('2d');
+
+        if (this._textDirty) {
+            this._reflowLines();
+        }
+
+        // Calculate the canvas-space sizes of the padded text area and full text bubble
+        const paddedWidth = this._textAreaSize.width;
+        const paddedHeight = this._textAreaSize.height;
+
+        // Resize the canvas to the correct screen-space size
+        this._canvas.width = Math.ceil(this._size[0] * scale);
+        this._canvas.height = Math.ceil(this._size[1] * scale);
+        this._restyleCanvas();
+
+        // Reset the transform before clearing to ensure 100% clearage
+        ctx.setTransform(1, 0, 0, 1, 0, 0);
+        ctx.clearRect(0, 0, this._canvas.width, this._canvas.height);
+
+        ctx.scale(scale, scale);
+        ctx.translate(BubbleStyle.STROKE_WIDTH * 0.5, BubbleStyle.STROKE_WIDTH * 0.5);
+
+        // If the text bubble points leftward, flip the canvas
+        ctx.save();
+        if (this._pointsLeft) {
+            ctx.scale(-1, 1);
+            ctx.translate(-paddedWidth, 0);
+        }
+
+        // Draw the bubble's rounded borders
+        ctx.moveTo(BubbleStyle.CORNER_RADIUS, paddedHeight);
+        ctx.arcTo(0, paddedHeight, 0, paddedHeight - BubbleStyle.CORNER_RADIUS, BubbleStyle.CORNER_RADIUS);
+        ctx.arcTo(0, 0, paddedWidth, 0, BubbleStyle.CORNER_RADIUS);
+        ctx.arcTo(paddedWidth, 0, paddedWidth, paddedHeight, BubbleStyle.CORNER_RADIUS);
+        ctx.arcTo(paddedWidth, paddedHeight, paddedWidth - BubbleStyle.CORNER_RADIUS, paddedHeight,
+            BubbleStyle.CORNER_RADIUS);
+
+        // Translate the canvas so we don't have to do a bunch of width/height arithmetic
+        ctx.save();
+        ctx.translate(paddedWidth - BubbleStyle.CORNER_RADIUS, paddedHeight);
+
+        // Draw the bubble's "tail"
+        if (this._bubbleType === 'say') {
+            // For a speech bubble, draw one swoopy thing
+            ctx.bezierCurveTo(0, 4, 4, 8, 4, 10);
+            ctx.arcTo(4, 12, 2, 12, 2);
+            ctx.bezierCurveTo(-1, 12, -11, 8, -16, 0);
+
+            ctx.closePath();
+        } else {
+            // For a thinking bubble, draw a partial circle attached to the bubble...
+            ctx.arc(-16, 0, 4, 0, Math.PI);
+
+            ctx.closePath();
+
+            // and two circles detached from it
+            ctx.moveTo(-7, 7.25);
+            ctx.arc(-9.25, 7.25, 2.25, 0, Math.PI * 2);
+
+            ctx.moveTo(0, 9.5);
+            ctx.arc(-1.5, 9.5, 1.5, 0, Math.PI * 2);
+        }
+
+        // Un-translate the canvas and fill + stroke the text bubble
+        ctx.restore();
+
+        ctx.fillStyle = BubbleStyle.COLORS.BUBBLE_FILL;
+        ctx.strokeStyle = BubbleStyle.COLORS.BUBBLE_STROKE;
+        ctx.lineWidth = BubbleStyle.STROKE_WIDTH;
+
+        ctx.stroke();
+        ctx.fill();
+
+        // Un-flip the canvas if it was flipped
+        ctx.restore();
+
+        // Draw each line of text
+        ctx.fillStyle = BubbleStyle.COLORS.TEXT_FILL;
+        ctx.font = `${BubbleStyle.FONT_SIZE}px ${BubbleStyle.FONT}, sans-serif`;
+        const lines = this._lines;
+        for (let lineNumber = 0; lineNumber < lines.length; lineNumber++) {
+            const line = lines[lineNumber];
+            ctx.fillText(
+                line,
+                BubbleStyle.PADDING,
+                BubbleStyle.PADDING + (BubbleStyle.LINE_HEIGHT * lineNumber) +
+                    (BubbleStyle.FONT_HEIGHT_RATIO * BubbleStyle.FONT_SIZE)
+            );
+        }
+
+        this._renderedScale = scale;
+    }
+
+    /**
+     * @param {Array<number>} scale - The scaling factors to be used, each in the [0,100] range.
+     * @return {WebGLTexture} The GL texture representation of this skin when drawing at the given scale.
+     */
+    getTexture (scale) {
+        // The texture only ever gets uniform scale. Take the larger of the two axes.
+        const scaleMax = scale ? Math.max(Math.abs(scale[0]), Math.abs(scale[1])) : 100;
+        const requestedScale = scaleMax / 100;
+
+        // If we already rendered the text bubble at this scale, we can skip re-rendering it.
+        if (this._textureDirty || this._renderedScale !== requestedScale) {
+            this._renderTextBubble(requestedScale);
+            this._textureDirty = false;
+
+            const context = this._canvas.getContext('2d');
+            const textureData = context.getImageData(0, 0, this._canvas.width, this._canvas.height);
+
+            const gl = this._renderer.gl;
+
+            if (this._texture === null) {
+                const textureOptions = {
+                    auto: true,
+                    wrap: gl.CLAMP_TO_EDGE,
+                    src: textureData
+                };
+
+                this._texture = twgl.createTexture(gl, textureOptions);
+            }
+    
+            gl.bindTexture(gl.TEXTURE_2D, this._texture);
+            gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, textureData);
+            this._silhouette.update(textureData);
+        }
+
+        return this._texture;
+    }
+}
+
+module.exports = TextBubbleSkin;

src/playground/playground.js

@@ -6,6 +6,8 @@ var fudge = 90;
 var renderer = new ScratchRender(canvas);
 renderer.setLayerGroupOrdering(['group1']);
 
+window.renderer = renderer;
+
 var drawableID = renderer.createDrawable('group1');
 renderer.updateDrawableProperties(drawableID, {
     position: [0, 0],
@@ -15,12 +17,13 @@ renderer.updateDrawableProperties(drawableID, {
 
 var drawableID2 = renderer.createDrawable('group1');
 var wantBitmapSkin = false;
+var wantTextSkin = true;
 
 // Bitmap (squirrel)
 var image = new Image();
 image.addEventListener('load', () => {
     var bitmapSkinId = renderer.createBitmapSkin(image);
-    if (wantBitmapSkin) {
+    if (wantBitmapSkin && !wantTextSkin) {
         renderer.updateDrawableProperties(drawableID2, {
             skinId: bitmapSkinId
         });
@@ -33,7 +36,7 @@ image.src = 'https://cdn.assets.scratch.mit.edu/internalapi/asset/7e24c99c1b853e
 var xhr = new XMLHttpRequest();
 xhr.addEventListener('load', function () {
     var skinId = renderer.createSVGSkin(xhr.responseText);
-    if (!wantBitmapSkin) {
+    if (!wantBitmapSkin && !wantTextSkin) {
         renderer.updateDrawableProperties(drawableID2, {
             skinId: skinId
         });
@@ -42,6 +45,11 @@ xhr.addEventListener('load', function () {
 xhr.open('GET', 'https://cdn.assets.scratch.mit.edu/internalapi/asset/f88bf1935daea28f8ca098462a31dbb0.svg/get/');
 xhr.send();
 
+var skinId = renderer.createTextSkin("think", "testing text bubble", false);
+renderer.updateDrawableProperties(drawableID2, {
+    skinId: skinId
+});
+
 var posX = 0;
 var posY = 0;
 var scaleX = 100;
@@ -81,7 +89,7 @@ const handleFudgeChanged = function (event) {
         props.direction = fudge;
         break;
     case 'scalex':
-        props.scale = [fudge, scaleY];
+        props.scale = [fudge, fudge];
         scaleX = fudge;
         break;
     case 'scaley':

src/util/canvas-measurement-provider.js

@@ -0,0 +1,41 @@
+class CanvasMeasurementProvider {
+    /**
+     * @param {CanvasRenderingContext2D} ctx - provides a canvas rendering context
+     * with 'font' set to the text style of the text to be wrapped.
+     */
+    constructor (ctx) {
+        this._ctx = ctx;
+        this._cache = {};
+    }
+
+
+    // We don't need to set up or tear down anything here. Should these be removed altogether?
+
+    /**
+     * Called by the TextWrapper before a batch of zero or more calls to measureText().
+     */
+    beginMeasurementSession () {
+        
+    }
+
+    /**
+     * Called by the TextWrapper after a batch of zero or more calls to measureText().
+     */
+    endMeasurementSession () {
+        
+    }
+
+    /**
+     * Measure a whole string as one unit.
+     * @param {string} text - the text to measure.
+     * @returns {number} - the length of the string.
+     */
+    measureText (text) {
+        if (!this._cache[text]) {
+            this._cache[text] = this._ctx.measureText(text).width;
+        }
+        return this._cache[text];
+    }
+}
+
+module.exports = CanvasMeasurementProvider;

src/util/svg-text-bubble.js

@@ -1,205 +0,0 @@
-const SVGTextWrapper = require('./svg-text-wrapper');
-const SvgRenderer = require('scratch-svg-renderer').SVGRenderer;
-
-const MAX_LINE_LENGTH = 170;
-const MIN_WIDTH = 50;
-const STROKE_WIDTH = 4;
-
-class SVGTextBubble {
-    constructor () {
-        this.svgRenderer = new SvgRenderer();
-        this.svgTextWrapper = new SVGTextWrapper(this.makeSvgTextElement);
-        this._textSizeCache = {};
-    }
-
-    /**
-     * @return {SVGElement} an SVG text node with the properties that we want for speech bubbles.
-     */
-    makeSvgTextElement () {
-        const svgText = document.createElementNS('http://www.w3.org/2000/svg', 'text');
-        svgText.setAttribute('alignment-baseline', 'text-before-edge');
-        svgText.setAttribute('font-size', '14');
-        svgText.setAttribute('fill', '#575E75');
-        // TODO Do we want to use the new default sans font instead of Helvetica?
-        svgText.setAttribute('font-family', 'Helvetica');
-        return svgText;
-    }
-
-    _speechBubble (w, h, radius, pointsLeft) {
-        let pathString = `
-            M 0 ${radius}
-            A ${radius} ${radius} 0 0 1 ${radius} 0
-            L ${w - radius} 0
-            A ${radius} ${radius} 0 0 1 ${w} ${radius}
-            L ${w} ${h - radius}
-            A ${radius} ${radius} 0 0 1 ${w - radius} ${h}`;
-
-        if (pointsLeft) {
-            pathString += `
-                L 32 ${h}
-                c -5 8 -15 12 -18 12
-                a 2 2 0 0 1 -2 -2
-                c 0 -2 4 -6 4 -10`;
-        } else {
-            pathString += `
-                L ${w - 16} ${h}
-                c 0 4 4 8 4 10
-                a 2 2 0 0 1 -2 2
-                c -3 0 -13 -4 -18 -12`;
-        }
-
-        pathString += `
-            L ${radius} ${h}
-            A ${radius} ${radius} 0 0 1 0 ${h - radius}
-            Z`;
-
-        return `
-            <g>
-                <path
-                  d="${pathString}"
-                  stroke="rgba(0, 0, 0, 0.15)"
-                  stroke-width="${STROKE_WIDTH}"
-                  fill="rgba(0, 0, 0, 0.15)"
-                  stroke-line-join="round"
-              />
-              <path
-                d="${pathString}"
-                stroke="none"
-                fill="white" />
-            </g>`;
-    }
-
-    _thinkBubble (w, h, radius, pointsLeft) {
-        const e1rx = 2.25;
-        const e1ry = 2.25;
-        const e2rx = 1.5;
-        const e2ry = 1.5;
-        const e1x = 16 + 7 + e1rx;
-        const e1y = 5 + h + e1ry;
-        const e2x = 16 + e2rx;
-        const e2y = 8 + h + e2ry;
-        const insetR = 4;
-        const pInset1 = 12 + radius;
-        const pInset2 = pInset1 + (2 * insetR);
-
-        let pathString = `
-            M 0 ${radius}
-            A ${radius} ${radius} 0 0 1 ${radius} 0
-            L ${w - radius} 0
-            A ${radius} ${radius} 0 0 1 ${w} ${radius}
-            L ${w} ${h - radius}
-            A ${radius} ${radius} 0 0 1 ${w - radius} ${h}`;
-
-        if (pointsLeft) {
-            pathString += `
-                L ${pInset2} ${h}
-                A ${insetR} ${insetR} 0 0 1 ${pInset2 - insetR} ${h + insetR}
-                A ${insetR} ${insetR} 0 0 1 ${pInset1} ${h}`;
-        } else {
-            pathString += `
-                L ${w - pInset1} ${h}
-                A ${insetR} ${insetR} 0 0 1 ${w - pInset1 - insetR} ${h + insetR}
-                A ${insetR} ${insetR} 0 0 1 ${w - pInset2} ${h}`;
-        }
-
-        pathString += `
-            L ${radius} ${h}
-            A ${radius} ${radius} 0 0 1 0 ${h - radius}
-            Z`;
-
-        const ellipseSvg = (cx, cy, rx, ry) => `
-            <g>
-                <ellipse
-                    cx="${cx}" cy="${cy}"
-                    rx="${rx}" ry="${ry}"
-                    fill="rgba(0, 0, 0, 0.15)"
-                    stroke="rgba(0, 0, 0, 0.15)"
-                    stroke-width="${STROKE_WIDTH}"
-                />
-                <ellipse
-                    cx="${cx}" cy="${cy}"
-                    rx="${rx}" ry="${ry}"
-                    fill="white"
-                    stroke="none"
-                />
-            </g>`;
-        let ellipses = [];
-        if (pointsLeft) {
-            ellipses = [
-                ellipseSvg(e1x, e1y, e1rx, e1ry),
-                ellipseSvg(e2x, e2y, e2rx, e2ry)
-            ];
-        } else {
-            ellipses = [
-                ellipseSvg(w - e1x, e1y, e1rx, e1ry),
-                ellipseSvg(w - e2x, e2y, e2rx, e2ry)
-            ];
-        }
-
-        return `
-             <g>
-                <path d="${pathString}" stroke="rgba(0, 0, 0, 0.15)" stroke-width="${STROKE_WIDTH}"
-                    fill="rgba(0, 0, 0, 0.15)" />
-                <path d="${pathString}" stroke="none" fill="white" />
-                ${ellipses.join('\n')}
-            </g>`;
-    }
-
-    _getTextSize (textFragment) {
-        const svgString = this._wrapSvgFragment(textFragment);
-        if (!this._textSizeCache[svgString]) {
-            this._textSizeCache[svgString] = this.svgRenderer.measure(svgString);
-            if (this._textSizeCache[svgString].height === 0) {
-                // The speech bubble is empty, so use the height of a single line with content (or else it renders
-                // weirdly, see issue #302).
-                const dummyFragment = this._buildTextFragment('X');
-                this._textSizeCache[svgString] = this._getTextSize(dummyFragment);
-            }
-        }
-        return this._textSizeCache[svgString];
-    }
-
-    _wrapSvgFragment (fragment, width, height) {
-        let svgString = `<svg xmlns="http://www.w3.org/2000/svg" version="1.1"`;
-        if (width && height) {
-            const fullWidth = width + STROKE_WIDTH;
-            const fullHeight = height + STROKE_WIDTH + 12;
-            svgString = `${svgString} viewBox="
-                ${-STROKE_WIDTH / 2} ${-STROKE_WIDTH / 2} ${fullWidth} ${fullHeight}"
-                width="${fullWidth}" height="${fullHeight}">`;
-        } else {
-            svgString = `${svgString}>`;
-        }
-        svgString = `${svgString} ${fragment} </svg>`;
-        return svgString;
-    }
-
-    _buildTextFragment (text) {
-        const textNode = this.svgTextWrapper.wrapText(MAX_LINE_LENGTH, text);
-        const serializer = new XMLSerializer();
-        return serializer.serializeToString(textNode);
-    }
-
-    buildString (type, text, pointsLeft) {
-        this.type = type;
-        this.pointsLeft = pointsLeft;
-        this._textFragment = this._buildTextFragment(text);
-
-        let fragment = '';
-
-        const radius = 16;
-        const {x, y, width, height} = this._getTextSize(this._textFragment);
-        const padding = 10;
-        const fullWidth = Math.max(MIN_WIDTH, width) + (2 * padding);
-        const fullHeight = height + (2 * padding);
-        if (this.type === 'say') {
-            fragment += this._speechBubble(fullWidth, fullHeight, radius, this.pointsLeft);
-        } else {
-            fragment += this._thinkBubble(fullWidth, fullHeight, radius, this.pointsLeft);
-        }
-        fragment += `<g transform="translate(${padding - x}, ${padding - y})">${this._textFragment}</g>`;
-        return this._wrapSvgFragment(fragment, fullWidth, fullHeight);
-    }
-}
-
-module.exports = SVGTextBubble;

src/util/svg-text-wrapper.js

@@ -1,127 +0,0 @@
-const TextWrapper = require('./text-wrapper');
-
-/**
- * Measure text by using a hidden SVG attached to the DOM.
- * For use with TextWrapper.
- */
-class SVGMeasurementProvider {
-    /**
-     * @param {function} makeTextElement - provides a text node of an SVGElement
-     *     with the style of the text to be wrapped.
-     */
-    constructor (makeTextElement) {
-        this._svgRoot = null;
-        this._cache = {};
-        this.makeTextElement = makeTextElement;
-    }
-
-    /**
-     * Detach the hidden SVG element from the DOM and forget all references to it and its children.
-     */
-    dispose () {
-        if (this._svgRoot) {
-            this._svgRoot.parentElement.removeChild(this._svgRoot);
-            this._svgRoot = null;
-            this._svgText = null;
-        }
-    }
-
-    /**
-     * Called by the TextWrapper before a batch of zero or more calls to measureText().
-     */
-    beginMeasurementSession () {
-        if (!this._svgRoot) {
-            this._init();
-        }
-    }
-
-    /**
-     * Called by the TextWrapper after a batch of zero or more calls to measureText().
-     */
-    endMeasurementSession () {
-        this._svgText.textContent = '';
-        this.dispose();
-    }
-
-    /**
-     * Measure a whole string as one unit.
-     * @param {string} text - the text to measure.
-     * @returns {number} - the length of the string.
-     */
-    measureText (text) {
-        if (!this._cache[text]) {
-            this._svgText.textContent = text;
-            this._cache[text] = this._svgText.getComputedTextLength();
-        }
-        return this._cache[text];
-    }
-
-    /**
-     * Create a simple SVG containing a text node, hide it, and attach it to the DOM. The text node will be used to
-     * collect text measurements. The SVG must be attached to the DOM: otherwise measurements will generally be zero.
-     * @private
-     */
-    _init () {
-        const svgNamespace = 'http://www.w3.org/2000/svg';
-
-        const svgRoot = document.createElementNS(svgNamespace, 'svg');
-        const svgGroup = document.createElementNS(svgNamespace, 'g');
-        const svgText = this.makeTextElement();
-
-        // hide from the user, including screen readers
-        svgRoot.setAttribute('style', 'position:absolute;visibility:hidden');
-
-        document.body.appendChild(svgRoot);
-        svgRoot.appendChild(svgGroup);
-        svgGroup.appendChild(svgText);
-
-        /**
-         * The root SVG element.
-         * @type {SVGSVGElement}
-         * @private
-         */
-        this._svgRoot = svgRoot;
-
-        /**
-         * The leaf SVG element used for text measurement.
-         * @type {SVGTextElement}
-         * @private
-         */
-        this._svgText = svgText;
-    }
-}
-
-/**
- * TextWrapper specialized for SVG text.
- */
-class SVGTextWrapper extends TextWrapper {
-    /**
-     * @param {function} makeTextElement - provides a text node of an SVGElement
-     *     with the style of the text to be wrapped.
-     */
-    constructor (makeTextElement) {
-        super(new SVGMeasurementProvider(makeTextElement));
-        this.makeTextElement = makeTextElement;
-    }
-
-    /**
-     * Wrap the provided text into lines restricted to a maximum width. See Unicode Standard Annex (UAX) #14.
-     * @param {number} maxWidth - the maximum allowed width of a line.
-     * @param {string} text - the text to be wrapped. Will be split on whitespace.
-     * @returns {SVGElement} wrapped text node
-     */
-    wrapText (maxWidth, text) {
-        const lines = super.wrapText(maxWidth, text);
-        const textElement = this.makeTextElement();
-        for (const line of lines) {
-            const tspanNode = document.createElementNS('http://www.w3.org/2000/svg', 'tspan');
-            tspanNode.setAttribute('x', '0');
-            tspanNode.setAttribute('dy', '1.2em');
-            tspanNode.textContent = line;
-            textElement.appendChild(tspanNode);
-        }
-        return textElement;
-    }
-}
-
-module.exports = SVGTextWrapper;

src/util/text-wrapper.js

@@ -16,7 +16,7 @@ const GraphemeBreaker = require('!ify-loader!grapheme-breaker');
  * break opportunities.
  * Reference material:
  * - Unicode Standard Annex #14: http://unicode.org/reports/tr14/
- * - Unicode Standard Annex #39: http://unicode.org/reports/tr29/
+ * - Unicode Standard Annex #29: http://unicode.org/reports/tr29/
  * - "JavaScript has a Unicode problem" by Mathias Bynens: https://mathiasbynens.be/notes/javascript-unicode
  */
 class TextWrapper {