| <!DOCTYPE html> |
| <meta charset="utf-8"> |
| <title>Canvas's ImageBitmapRenderingContext test</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <link rel="help" href="https://html.spec.whatwg.org/multipage/scripting.html#the-imagebitmap-rendering-context"> |
| <script> |
| var width = 10; |
| var height = 10; |
| |
| function testCanvas(ctx, r, g, b, a) |
| { |
| var color = ctx.getImageData(5, 5, 1, 1).data; |
| assert_array_equals(color, [r, g, b, a]); |
| } |
| |
| promise_test(function() { |
| function transferFromImageBitmapToBlobOffscreen(greenImage) { |
| var bitmapCanvas = new OffscreenCanvas(width,height); |
| var bitmapCtx = bitmapCanvas.getContext('bitmaprenderer'); |
| bitmapCtx.transferFromImageBitmap(greenImage); |
| |
| return bitmapCanvas.convertToBlob(); |
| } |
| |
| function drawBlobToCanvas(blob) { |
| // Make sure the bitmap renderer canvas is filled correctly. |
| var pngImage = new Image(); |
| var myCanvasToTest = document.createElement('canvas'); |
| myCanvasToTest.width = width; |
| myCanvasToTest.height = height; |
| |
| // Wait for the blob img to load. |
| return new Promise(function(resolve) { |
| pngImage.src = URL.createObjectURL(blob); |
| pngImage.onload = function() { |
| var myCtxToTest = myCanvasToTest.getContext('2d'); |
| myCtxToTest.drawImage(pngImage, 0, 0); |
| resolve(myCtxToTest); |
| }; |
| }); |
| } |
| |
| var greenCanvas = document.createElement('canvas'); |
| greenCanvas.width = width; |
| greenCanvas.height = height; |
| var greenCtx = greenCanvas.getContext('2d'); |
| greenCtx.fillStyle = '#0f0'; |
| greenCtx.fillRect(0, 0, width, height); |
| |
| return createImageBitmap(greenCanvas).then( |
| greenImage => transferFromImageBitmapToBlobOffscreen(greenImage) |
| ).then( |
| blob => drawBlobToCanvas(blob) |
| ).then( |
| ctx => testCanvas(ctx, 0, 255, 0, 255) |
| ); |
| },'Test that convertToBlob works and produce the expected image'); |
| |
| </script> |
