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https://github.com/web-platform-tests/wpt
26 December 2018, 22:31:15 UTC
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Tip revision: a619744eead89c5105c98040bf77f11c40eaa311 authored by Geoffrey Sneddon on 09 October 2018, 17:34:30 UTC
Only run Windows CI for tools/ changes
Tip revision: a619744
canvas-createImageBitmap-resize.html 
<!DOCTYPE HTML>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
function checkNoCrop(imageBitmap)
{
    var canvas = document.createElement("canvas");
    canvas.width = 50;
    canvas.height = 50;
    var ctx = canvas.getContext("2d");
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    ctx.drawImage(imageBitmap, 0, 0);
    var d = ctx.getImageData(0, 0, 1, 1).data;
    assert_array_equals(d, [255, 0, 0, 255], "This pixel should be red.");
    d = ctx.getImageData(39, 0, 1, 1).data;
    assert_array_equals(d, [0, 255, 0, 255], "This pixel should be green.");
    d = ctx.getImageData(0, 39, 1, 1).data;
    assert_array_equals(d, [0, 0, 255, 255], "This pixel should be blue.");
    d = ctx.getImageData(39, 39, 1, 1).data;
    assert_array_equals(d, [0, 0, 0, 255], "This pixel should be black.");
    d = ctx.getImageData(41, 41, 1, 1).data;
    assert_array_equals(d, [0, 0, 0, 0], "This pixel should be transparent black.");
}

function checkCrop(imageBitmap)
{
    var canvas = document.createElement("canvas");
    canvas.width = 50;
    canvas.height = 50;
    var ctx = canvas.getContext("2d");
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    ctx.drawImage(imageBitmap, 0, 0);
    var d = ctx.getImageData(0, 0, 1, 1).data;
    assert_array_equals(d, [255, 0, 0, 255], "This pixel should be red.");
    d = ctx.getImageData(19, 0, 1, 1).data;
    assert_array_equals(d, [0, 255, 0, 255], "This pixel should be green.");
    d = ctx.getImageData(0, 19, 1, 1).data;
    assert_array_equals(d, [0, 0, 255, 255], "This pixel should be blue.");
    d = ctx.getImageData(19, 19, 1, 1).data;
    assert_array_equals(d, [0, 0, 0, 255], "This pixel should be black.");
    d = ctx.getImageData(21, 21, 1, 1).data;
    assert_array_equals(d, [0, 0, 0, 0], "This pixel should be transparent black.");
}

function compareBitmaps(bitmap1, bitmap2)
{
    var canvas1 = document.createElement("canvas");
    var canvas2 = document.createElement("canvas");
    canvas1.width = 50;
    canvas1.height = 50;
    canvas2.width = 50;
    canvas2.height = 50;
    var ctx1 = canvas1.getContext("2d");
    var ctx2 = canvas2.getContext("2d");
    ctx1.clearRect(0, 0, canvas1.width, canvas1.height);
    ctx2.clearRect(0, 0, canvas2.width, canvas2.height);
    ctx1.drawImage(bitmap1, 0, 0);
    ctx2.drawImage(bitmap2, 0, 0);
    var data1 = ctx1.getImageData(0, 0, 50, 50).data;
    var data2 = ctx2.getImageData(0, 0, 50, 50).data;
    var dataMatched = true;
    for (var i = 0; i < data1.length; i++) {
        if (data1[i] != data2[i]) {
            dataMatched = false;
            break;
        }
    }
    assert_false(dataMatched);
}

function testImageBitmap(source)
{
    return Promise.all([
        createImageBitmap(source, {resizeWidth: 40, resizeHeight: 40, resizeQuality: "high"}),
        createImageBitmap(source, {resizeWidth: 40, resizeHeight: 40, resizeQuality: "medium"}),
        createImageBitmap(source, {resizeWidth: 40, resizeHeight: 40, resizeQuality: "low"}),
        createImageBitmap(source, {resizeWidth: 40, resizeHeight: 40, resizeQuality: "pixelated"}),
        createImageBitmap(source, 5, 5, 10, 10, {resizeWidth: 20, resizeHeight: 20, resizeQuality: "high"}),
        createImageBitmap(source, 5, 5, 10, 10, {resizeWidth: 20, resizeHeight: 20, resizeQuality: "medium"}),
        createImageBitmap(source, 5, 5, 10, 10, {resizeWidth: 20, resizeHeight: 20, resizeQuality: "low"}),
        createImageBitmap(source, 5, 5, 10, 10, {resizeWidth: 20, resizeHeight: 20, resizeQuality: "pixelated"}),
    ]).then(([noCropHigh, noCropMedium, noCropLow, noCropPixelated, cropHigh, cropMedium, cropLow, cropPixelated]) => {
        checkNoCrop(noCropHigh);
        checkNoCrop(noCropMedium);
        checkNoCrop(noCropLow);
        checkNoCrop(noCropPixelated);
        checkCrop(cropHigh);
        checkCrop(cropMedium);
        checkCrop(cropLow);
        checkCrop(cropPixelated);
        // Brute-force comparison among all bitmaps is too expensive
        compareBitmaps(noCropHigh, noCropMedium);
        compareBitmaps(noCropLow, noCropPixelated);
        compareBitmaps(cropHigh, cropMedium);
        compareBitmaps(cropLow, cropPixelated);
    });
}

function initializeTestCanvas()
{
    var testCanvas = document.createElement("canvas");
    testCanvas.width = 20;
    testCanvas.height = 20;
    var testCtx = testCanvas.getContext("2d");
    testCtx.fillStyle = "rgb(255, 0, 0)";
    testCtx.fillRect(0, 0, 10, 10);
    testCtx.fillStyle = "rgb(0, 255, 0)";
    testCtx.fillRect(10, 0, 10, 10);
    testCtx.fillStyle = "rgb(0, 0, 255)";
    testCtx.fillRect(0, 10, 10, 10);
    testCtx.fillStyle = "rgb(0, 0, 0)";
    testCtx.fillRect(10, 10, 10, 10);
    return testCanvas;
}

// Blob
promise_test(function() {
    return new Promise((resolve, reject) => {
        var xhr = new XMLHttpRequest();
        xhr.open("GET", '/images/pattern.png');
        xhr.responseType = 'blob';
        xhr.send();
        xhr.onload = function() {
            resolve(xhr.response);
        };
    }).then(testImageBitmap);
}, 'createImageBitmap from a Blob with resize option.');

// HTMLCanvasElement
promise_test(function() {
    var testCanvas = initializeTestCanvas();
    return testImageBitmap(testCanvas);
}, 'createImageBitmap from a HTMLCanvasElement with resize option.');

// HTMLImageElement
promise_test(function() {
    return new Promise((resolve, reject) => {
        var image = new Image();
        image.onload = function() {
            resolve(image);
        }
        image.src = '/images/pattern.png'
    }).then(testImageBitmap);
}, 'createImageBitmap from a HTMLImageElement with resize option.');

// ImageBitmap
promise_test(function() {
    var testCanvas = initializeTestCanvas();
    return createImageBitmap(testCanvas).then(testImageBitmap);
}, 'createImageBitmap from an ImageBitmap with resize option.');

// ImageData
promise_test(function() {
    var canvas = initializeTestCanvas();
    var ctx = canvas.getContext("2d");
    var data = ctx.getImageData(0, 0, 20, 20);
    return testImageBitmap(data);
}, 'createImageBitmap from an ImageData with resize option.');
</script>
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