<!--
Copyright (c) 2019 The Khronos Group Inc.
Use of this source code is governed by an MIT-style license that can be
found in the LICENSE.txt file.
-->

<!DOCTYPE html>
<html>
  <head>
<meta charset="utf-8">
    <title>WebGL Vertex Attrib Context Switch 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="one" width="50" height="50">
</canvas>
<canvas id="two" width="50" height="50">
</canvas>
<div id="description"></div>
<div id="console"></div>
<script>
"use strict";
description("tests that vertex attrib value is preserved across context switches");
var wtu = WebGLTestUtils;
var positionLocation = 0;
var colorLocation = 1;
var gridRes = 1;

var canvas1 = document.getElementById("one");
var gl1 = wtu.create3DContext(canvas1);
var program1 = wtu.setupSimpleVertexColorProgram(gl1, positionLocation, colorLocation);
gl1.vertexAttrib4f(colorLocation, 0.0, 1.0, 0.0, 1.0);
wtu.setupIndexedQuad(gl1, gridRes, positionLocation);
wtu.clearAndDrawIndexedQuad(gl1, gridRes);
wtu.checkCanvas(gl1, [0, 255, 0, 255], "should be green 1");

var canvas2 = document.getElementById("two");
var gl2 = wtu.create3DContext(canvas2);
var program2 = wtu.setupSimpleVertexColorProgram(gl2, positionLocation, colorLocation);
wtu.setupIndexedQuad(gl2, gridRes, positionLocation);
wtu.clearAndDrawIndexedQuad(gl2, gridRes);
wtu.checkCanvas(gl2, [0, 0, 0, 255], "should be black 1");

wtu.checkCanvas(gl1, [0, 255, 0, 255], "should be green 2");

wtu.clearAndDrawIndexedQuad(gl2, gridRes);
wtu.checkCanvas(gl2, [0, 0, 0, 255], "should be black 2");

wtu.clearAndDrawIndexedQuad(gl1, gridRes);
wtu.checkCanvas(gl1, [0, 255, 0, 255], "should be green 3");

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

</body>
</html>

