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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.
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Driver Bug - Uniforms should no lose values</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" width="512" height="256"> </canvas>
<div id="description"></div>
<div id="console"></div>
<script id="vshader" type="x-shader/x-vertex">
uniform float k,u;
uniform mat4 l;
attribute vec3 a;
void main(){
  gl_Position=l*vec4(a,1.+u+k);
}
</script>
<script id="fshader" type="x-shader/x-fragment">
precision mediump float;
uniform float w,x,y,z;
void main() {
 gl_FragColor=vec4(1.-y,y,w+x+z,1);
}
</script>
<script>
"use strict";
// Certain drivers fail this test. Specifically Mac NVidia GT 330 on OSX 10.8.2
description();
debug("");
var wtu = WebGLTestUtils;
function test() {
  var gl = wtu.create3DContext("canvas");
  if (!gl) {
    testFailed("context does not exist");
    return;
  }

  wtu.setupUnitQuad(gl);
  var program = wtu.setupProgram(gl, ["vshader", "fshader"], ["a"], undefined, true);

  var setUniformf = function(name, val) {
    var loc = gl.getUniformLocation(program, name);
    var func = 'uniform' + val.length + 'fv';
    gl[func](loc, val);
  };

  var setUniformMat = function(name, val) {
    var loc = gl.getUniformLocation(program, name);
    var func = 'uniformMatrix' + Math.sqrt(val.length) + 'fv';
    gl[func](loc, false, val);
  };

  setUniformMat('l', [1, 0 ,0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1]);
  gl.viewport(0, 0, 256, 256);
  setUniformf('y', [0]);
  wtu.drawUnitQuad(gl);
  gl.viewport(256, 0, 256, 256);
  setUniformf('y', [1]);
  wtu.drawUnitQuad(gl);
  wtu.checkCanvasRect(gl, 0, 0, 256, 256, [255, 0, 0, 255]);
  wtu.checkCanvasRect(gl, 256, 0, 256, 256, [0, 255, 0, 255]);

  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "there should be no errors");
}
test();
var successfullyParsed = true;
</script>
<script src="../../../js/js-test-post.js"></script>
</body>
</html>

