canvas_shadows_001.htm

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This WPT test may be referenced by the following Test IDs:
- /html/canvas/element/manual/shadows/canvas_shadows_001.htm - WPT Dashboard Interop Dashboard

<!doctype HTML>

<html>

    <head>

        <title>HTML5 Canvas Test: Shadows for linear gradients</title>

        <script src="/resources/testharness.js"></script>

        <script src="/resources/testharnessreport.js"></script>

        <link rel="author" title="Microsoft" href="http://www.microsoft.com" />

        <link rel="help" href="http://www.w3.org/TR/2dcontext/#shadows" />

        <meta name="assert" content="Shadows must be drawn for linear gradients." />

        <script type="text/javascript">

            async_test(function(t) {

              window.addEventListener("load", t.step_func_done(function runTest() {

                var canvas = document.getElementById("canvas1");

                var ctx = canvas.getContext("2d");

                // Draw a red rectangle.

                ctx.fillStyle = "rgba(255, 0, 0, 1.0)";

                ctx.fillRect(150, 0, 100, 50);

                // Set shadow styles to draw a black shadow to overlap the red rectangle.

                ctx.shadowOffsetX = 150;

                ctx.shadowColor = "rgba(0, 0, 0, 1.0)";

                // Draw a left to right, green-to-blue linear gradient.

                var lingrad = ctx.createLinearGradient(0, 50, 100, 50);

                lingrad.addColorStop(0, "rgba(0, 255, 0, 1.0)");

                lingrad.addColorStop(1, "rgba(0, 0, 255, 1.0)");

                ctx.fillStyle = lingrad;

                ctx.fillRect(0, 0, 100, 50);

                // Check the red is gone

                var data = ctx.getImageData(150, 0, 100, 50);

                for (var i = 0; i < data.data.length; i += 4) {

                  var r = data.data[i];

                  var g = data.data[i+1];

                  var b = data.data[i+2];

                  var a = data.data[i+3];

                  assert_equals(r, 0, "r channel");

                  assert_equals(g, 0, "g channel");

                  assert_equals(b, 0, "b channel");

                  assert_equals(a, 0xFF, "a channel");

                for (var j = 0; j < data.data.length; j += 4) {

                  var r2 = data.data[j];

                  var g2 = data.data[j+1];

                  var b2 = data.data[j+2];

                  var a2 = data.data[j+3];

                  assert_false(r2 == 0xFF && g2 == 0 && b2 == 0 && a2 == 0xFF, "no red");

              }));

            }, "linear gradient fillRect draws shadow (black rectange)");

        </script>

    </head>

    <body>

        <p>Description: Shadows must be drawn for linear gradients.</p>

        <p>Test passes if there is one gradient filled rectangle and one black rectangle, and no red seen on the page.</p>

        <canvas id="canvas1" width="300" height="150">Browser does not support HTML5 Canvas.</canvas>

    </body>

</html>