| <!DOCTYPE html> |
| <title>Canvas.drawImage with narrow destination.</title> |
| <script src="../resources/js-test.js"></script> |
| <script> |
| function verifyCovered(imgData, offset, stride, length) { |
| while (length) { |
| if (imgData[offset + 3] === 0) |
| return false; |
| offset += stride * 4; |
| length--; |
| } |
| return true; |
| } |
| |
| ImageData.prototype.pixelOffset = function(x, y) { |
| return (x + y * this.width) * 4; |
| } |
| |
| var sourceImage = document.createElement("canvas"); |
| sourceImage.height = sourceImage.width = 1; |
| sourceImage.getContext("2d").fillRect(0, 0, 1, 1); |
| |
| var c = document.createElement("canvas"); |
| c.width = c.height = 100; |
| var ctx = c.getContext("2d"); |
| |
| // Thin horizontal image. |
| ctx.drawImage(sourceImage, 10, 5.5, 10, 0.95); |
| |
| // Thin vertical image. |
| ctx.drawImage(sourceImage, 5.5, 5, 0.95, 10); |
| |
| // Rotated 90 degrees |
| ctx.save(); |
| ctx.translate(20, 15); |
| ctx.rotate(Math.PI / 2); |
| ctx.drawImage(sourceImage, 0, -.5, 10, 0.95); |
| ctx.restore(); |
| |
| // Rotated -90 degrees |
| ctx.save(); |
| ctx.translate(25, 15); |
| ctx.rotate(-Math.PI / 2); |
| ctx.drawImage(sourceImage, -.5, 0, 0.95, 10); |
| ctx.restore(); |
| |
| imgData = ctx.getImageData(0, 0, c.width, c.height); |
| shouldBeTrue("verifyCovered(imgData.data, imgData.pixelOffset(10, 5), 1, 10)"); |
| shouldBeTrue("verifyCovered(imgData.data, imgData.pixelOffset(5, 5), imgData.width, 10)"); |
| shouldBeTrue("verifyCovered(imgData.data, imgData.pixelOffset(25, 15), 1, 10)"); |
| shouldBeTrue("verifyCovered(imgData.data, imgData.pixelOffset(20, 15), imgData.width, 10)"); |
| |
| successfullyParsed = true; |
| </script> |