| <!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(bitmapCanvas, r, g, b, a) |
| { |
| var myCanvas = document.createElement('canvas'); |
| myCanvas.width = width; |
| myCanvas.height = height; |
| var myCtx = myCanvas.getContext('2d'); |
| myCtx.drawImage(bitmapCanvas, 0, 0); |
| var color = myCtx.getImageData(5, 5, 1, 1).data; |
| assert_array_equals(color, [r, g, b, a]); |
| } |
| |
| promise_test(function() { |
| function testTransferFromImageBitmapNullability(greenImage, redImage) { |
| var bitmapCanvas = new OffscreenCanvas(width,height); |
| var bitmapCtx = bitmapCanvas.getContext('bitmaprenderer'); |
| bitmapCtx.transferFromImageBitmap(greenImage); |
| |
| // Make sure the bitmap renderer canvas is filled correctly. |
| testCanvas(bitmapCanvas, 0, 255, 0, 255); |
| |
| // Test if passing null resets the bitmap renderer canvas. |
| // Drawing the resetted canvas cannot change the destination canvas. |
| bitmapCtx.transferFromImageBitmap(null); |
| testCanvas(bitmapCanvas, 0, 0, 0, 0); |
| |
| // Test if we can redraw the bitmap canvas correctly after reset. |
| bitmapCtx.transferFromImageBitmap(redImage); |
| testCanvas(bitmapCanvas, 255, 0, 0, 255); |
| } |
| |
| 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); |
| |
| var redCanvas = document.createElement('canvas'); |
| redCanvas.width = width; |
| redCanvas.height = height; |
| var redCtx = redCanvas.getContext('2d'); |
| redCtx.fillStyle = '#f00'; |
| redCtx.fillRect(0, 0, width, height); |
| |
| return Promise.all([ |
| createImageBitmap(greenCanvas), |
| createImageBitmap(redCanvas), |
| ]).then(([greenImage, redImage]) => { |
| testTransferFromImageBitmapNullability(greenImage, redImage); |
| }); |
| },'Test that transferFromImageBitmap(null) discards the previously transferred image'); |
| |
| </script> |
