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<head>
<meta charset="utf-8">
<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>
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<div id="description"></div>
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<script>
"use strict";
description('Tests that index validation for drawElements works with large attribute buffers');

var wtu = WebGLTestUtils;
var context = wtu.create3DContext();
var program = wtu.loadStandardProgram(context);

context.useProgram(program);

// Create a small index buffer.
var indexObject = context.createBuffer();
context.bindBuffer(context.ELEMENT_ARRAY_BUFFER, indexObject);
var indexArray = new Uint16Array([0, 1, 2]);
context.bufferData(context.ELEMENT_ARRAY_BUFFER, indexArray, context.STATIC_DRAW);

// Create a large attribute buffer.
var vertexObject = context.createBuffer();
context.enableVertexAttribArray(0);
context.bindBuffer(context.ARRAY_BUFFER, vertexObject);
context.bufferData(context.ARRAY_BUFFER, new Float32Array(3 * 65536), context.STATIC_DRAW);
context.vertexAttribPointer(0, 3, context.FLOAT, false, 0, 0);

debug("Test large attribute buffer")
wtu.shouldGenerateGLError(context, context.NO_ERROR, "context.drawElements(context.TRIANGLES, 3, context.UNSIGNED_SHORT, 0)");

// Enlarge the attribute buffer slightly.
debug("Test even larger attribute buffer")
context.bufferData(context.ARRAY_BUFFER, new Float32Array(3 * 65536 + 3), context.STATIC_DRAW);
wtu.shouldGenerateGLError(context, context.NO_ERROR, "context.drawElements(context.TRIANGLES, 3, context.UNSIGNED_SHORT, 0)");

debug("")
var successfullyParsed = true;
</script>

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