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"use strict";
description('Test that client data is always copied during bufferData and bufferSubData calls, because otherwise the data the GL uses to draw may differ from that checked by the index validation code.')

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

context.useProgram(program);
var vertexObject = context.createBuffer();
context.enableVertexAttribArray(0);
context.bindBuffer(context.ARRAY_BUFFER, vertexObject);
// 4 vertices -> 2 triangles
context.bufferData(context.ARRAY_BUFFER, new Float32Array([ 0,0,0, 0,1,0, 1,0,0, 1,1,0 ]), context.STATIC_DRAW);
context.vertexAttribPointer(0, 3, context.FLOAT, false, 0, 0);

var indexObject = context.createBuffer();

context.bindBuffer(context.ELEMENT_ARRAY_BUFFER, indexObject);
var indices = new Uint16Array([ 10000, 0, 1, 2, 3, 10000 ]);
context.bufferData(context.ELEMENT_ARRAY_BUFFER, indices, context.STATIC_DRAW);
wtu.shouldGenerateGLError(context, context.NO_ERROR, "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 2)");
var indexValidationError = wtu.shouldGenerateGLError(context,
                                                     [context.INVALID_OPERATION, context.NO_ERROR],
                                                     "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 0)");
wtu.shouldGenerateGLError(context, indexValidationError, "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 4)");
indices[0] = 2;
indices[5] = 1;
wtu.shouldGenerateGLError(context, context.NO_ERROR, "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 2)");
wtu.shouldGenerateGLError(context, indexValidationError, "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 0)");
wtu.shouldGenerateGLError(context, indexValidationError, "context.drawElements(context.TRIANGLE_STRIP, 4, context.UNSIGNED_SHORT, 4)");

debug("")
var successfullyParsed = true;
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