| <!DOCTYPE html> |
| <html> |
| <style> |
| canvas { |
| width: 100px; |
| height: 100px; |
| } |
| </style> |
| <body> |
| <div> |
| <p>Frames of a 3-frame animated image with loopCount = 1:</p> |
| <canvas id="canvas-1"></canvas> |
| <canvas id="canvas-2"></canvas> |
| <canvas id="canvas-3"></canvas> |
| <canvas id="canvas-4"></canvas> |
| </div> |
| <div> |
| <p>Frames of a 3-frame animated image with loopCount = 2:</p> |
| <canvas id="canvas-a"></canvas> |
| <canvas id="canvas-b"></canvas> |
| <canvas id="canvas-c"></canvas> |
| <canvas id="canvas-d"></canvas> |
| <canvas id="canvas-e"></canvas> |
| <canvas id="canvas-f"></canvas> |
| <canvas id="canvas-g"></canvas> |
| </div> |
| <script> |
| function drawFrame(image, canvasId) { |
| return new Promise((resolve) => { |
| let canvas = document.getElementById("canvas-" + canvasId); |
| let context = canvas.getContext("2d"); |
| context.drawImage(image, 0, 0, canvas.width, canvas.height); |
| setTimeout(() => { |
| resolve(String.fromCharCode(canvasId.charCodeAt() + 1)); |
| }, 30); |
| }); |
| } |
| |
| function drawImage(image, canvasId, frameCount) { |
| let promise = drawFrame(image, canvasId); |
| for (let frame = 1; frame < frameCount; ++frame) { |
| promise = promise.then((canvasId) => { |
| return drawFrame(image, canvasId); |
| }); |
| } |
| return promise; |
| } |
| |
| function loadImage(src, canvasId, frameCount) { |
| return new Promise((resolve) => { |
| let image = new Image; |
| image.onload = (() => { |
| drawImage(image, canvasId, frameCount).then(resolve); |
| }); |
| image.src = src; |
| }); |
| } |
| |
| (function() { |
| if (window.internals) |
| internals.clearMemoryCache(); |
| |
| if (window.testRunner) |
| testRunner.waitUntilDone(); |
| |
| var images = [ |
| { src: "resources/animated-red-green-blue-repeat-1.gif", canvasId: '1', frameCount: 4 }, |
| { src: "resources/animated-red-green-blue-repeat-2.gif", canvasId: 'a', frameCount: 7 } |
| ]; |
| |
| var promises = []; |
| |
| for (let image of images) |
| promises.push(loadImage(image.src, image.canvasId, image.frameCount)); |
| |
| Promise.all(promises).then(() => { |
| if (window.testRunner) |
| testRunner.notifyDone(); |
| }); |
| })(); |
| </script> |
| </body> |
| </html> |
