description("Test for supporting setTransform on canvas patterns"); function pixelValueAt(context, x, y) { var imageData = context.getImageData(x, y, 1, 1); return imageData.data; } function pixelToString(p) { return "[" + p[0] + ", " + p[1] + ", " + p[2] + ", " + p[3] + "]" } function pixelShouldBe(context, x, y, expectedPixelString) { var pixel = pixelValueAt(context, x, y); var expectedPixel = eval(expectedPixelString); var pixelString = "pixel " + x + ", " + y; if (areArraysEqual(pixel, expectedPixel)) { testPassed(pixelString + " is " + pixelToString(pixel)); } else { testFailed(pixelString + " should be " + pixelToString(expectedPixel) + " was " + pixelToString(pixel)); } } function fillWithColor(context, canvas, color1, color2) { context.save(); context.fillStyle = color1; context.fillRect(0, 0, canvas.width / 2, canvas.height); context.fillStyle = color2; context.fillRect(canvas.width / 2, 0, canvas.width / 2, canvas.height); context.restore(); } var canvas = document.createElement("canvas"); canvas.height = 100; canvas.width = 100; canvas.style.height = "100"; canvas.style.width = "100"; document.body.appendChild(canvas); var patternImage = document.createElement("canvas"); patternImage.height = 10; patternImage.width = 20; var patternImageCtx = patternImage.getContext('2d'); fillWithColor(patternImageCtx, patternImage, "red", "green"); var greenPixel = pixelValueAt(patternImageCtx, 10, 0); var ctx = canvas.getContext('2d'); var pattern = ctx.createPattern(patternImage, "repeat-x"); var svgElement = document.createElementNS("http://www.w3.org/2000/svg", "svg"); var matrix = svgElement.createSVGMatrix(); matrix = matrix.translate(10, 0); pattern.setTransform(matrix); fillWithColor(ctx, canvas, "blue", "blue"); ctx.fillStyle = pattern; ctx.translate(20, 20); ctx.fillRect(0, 0, 10, 10); pixelShouldBe(ctx, 20, 20, "greenPixel");