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Copyright (c) 2019 The Khronos Group Inc.
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<html>
<head>
<meta charset="utf-8">
<title>WebGL Multi-Context Sampler Test</title>
<link rel="stylesheet" href="../../resources/js-test-style.css"/>
<script src="../../js/js-test-pre.js"></script>
<script src="../../js/webgl-test-utils.js"></script>
</head>
<body>
<canvas id="canvas_drawing" width="12" height="12"></canvas>
<div id="description"></div>
<div id="console"></div>
<script>
"use strict";
description("Tests that samplers' state doesn't leak across contexts");
debug("");
debug('Regression test for <a href="http://crbug.com/713127">http://crbug.com/713127</a>');

function runTest() {
    var wtu = WebGLTestUtils;
    var gl = wtu.create3DContext("canvas_drawing", undefined, 2);
    var texture = null;
    var color = [0, 255, 0, 255];

    if (!gl) {
        testFailed("WebGL context does not exist");
        return;
    }

    testPassed("WebGL context exists");

    wtu.setupTexturedQuad(gl);
    texture = gl.createTexture();
    // Create a texture bigger than 1x1 so that it would need mipmaps in
    // order to be complete.
    wtu.fillTexture(gl, texture, 2, 2, color, 0,
                    gl.RGBA, gl.UNSIGNED_BYTE, gl.RGBA8);
    // Set texture parameters so that this texture is complete.
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);

    // Set up a secondary context with a sampler bound to texture unit
    // 0. This should not interfere with the primary context.
    var altGL = wtu.create3DContext(undefined, undefined, 2);
    if (!altGL) {
        testFailed("Error creating secondary WebGL context");
        return;
    }

    var sampler = altGL.createSampler();
    // Note that the sampler's default TEXTURE_MIN_FILTER is
    // NEAREST_MIPMAP_LINEAR.
    altGL.bindSampler(0, sampler);
    altGL.clearColor(1, 0, 0, 1);
    altGL.clear(altGL.COLOR_BUFFER_BIT);
    wtu.checkCanvasRect(altGL, 0, 0, 1, 1, [ 255, 0, 0, 255 ],
                        "should be red");

    // Now switch back to the main context and draw the texture.
    gl.clearColor(1, 1, 1, 1);
    gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
    wtu.drawUnitQuad(gl);
    // The presence of the sampler on the other context should not
    // have interfered with the completeness of the texture.
    wtu.checkCanvasRect(gl, 0, 0, 1, 1, color,
                        "should be green");

    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "there should be no errors");
}

runTest();
var successfullyParsed = true;
</script>
<script src="../../js/js-test-post.js"></script>

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