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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
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<script type="application/javascript" src="../unit.js"></script>
<script type="application/javascript" src="../util.js"></script>
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Tests.startUnit = function () {
  var canvas = document.getElementById('gl');
  var gl = wrapGLContext(getGLContext(canvas));
  return [gl];
}

Tests.setup = function(gl) {
  var tex = gl.createTexture();
  gl.bindTexture(gl.TEXTURE_2D, tex);
  var texCubeMap = gl.createTexture();
  gl.bindTexture(gl.TEXTURE_CUBE_MAP, texCubeMap);
  return [gl]
}

Tests.teardown = function(gl,tex, texCubeMap) {
  gl.bindTexture(gl.TEXTURE_2D, null);
  gl.bindTexture(gl.TEXTURE_CUBE_MAP, null);
  gl.deleteTexture(tex);
  gl.deleteTexture(texCubeMap);
}

Tests.testTexImage2D = function(gl) {
  gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 0,0,1,1,0);
  gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 0,0,2,1,0);
  gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 0,0,1,2,0);
  gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 0,0,16,16,0);
  gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 15,15,1,1,0);
  var valid_targets = [
    gl.TEXTURE_2D,
    gl.TEXTURE_CUBE_MAP_POSITIVE_X,
    gl.TEXTURE_CUBE_MAP_NEGATIVE_X,
    gl.TEXTURE_CUBE_MAP_POSITIVE_Y,
    gl.TEXTURE_CUBE_MAP_NEGATIVE_Y,
    gl.TEXTURE_CUBE_MAP_POSITIVE_Z,
    gl.TEXTURE_CUBE_MAP_NEGATIVE_Z
  ];
  valid_targets.forEach(function(t) {
    assertOk(function(){gl.copyTexImage2D(t, 0, gl.RGBA, 0,0,1,1,0);});
  });
}
Tests.testRoundtrip = function(gl) {
    var sh = new Filter(gl, 'identity-flip-vert', 'identity-frag');
    gl.clearColor(1.0, 0.0, 0.0, 1.0);
    gl.clear(gl.COLOR_BUFFER_BIT);
    var buf = new Uint8Array(4);
    gl.readPixels(0,0,1,1,gl.RGBA, gl.UNSIGNED_BYTE, buf);
    assertEquals([255,0,0,255], [buf[0], buf[1], buf[2], buf[3]]);
    // red texture
    gl.copyTexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 0,0,16,16,0);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
    gl.clearColor(0.0, 0.0, 1.0, 1.0);
    gl.clear(gl.COLOR_BUFFER_BIT);
    // blue framebuffer
    gl.readPixels(0,0,1,1,gl.RGBA, gl.UNSIGNED_BYTE, buf);
    assertEquals([0,0,255,255], [buf[0], buf[1], buf[2], buf[3]]);
    sh.apply(); // paint it with texture
    gl.readPixels(0,0,1,1,gl.RGBA, gl.UNSIGNED_BYTE, buf);
    assertEquals([255,0,0,255], [buf[0], buf[1], buf[2], buf[3]]);
    sh.destroy();
}

Tests.endUnit = function(gl) {
}

</script>
<script id="identity-flip-vert" type="x-shader/x-vertex">
attribute vec3 Vertex;
attribute vec2 Tex;

varying vec4 texCoord0;
void main()
{
    texCoord0 = vec4(Tex.s, 1.0-Tex.t, 0.0, 0.0);
    gl_Position = vec4(Vertex, 1.0);
}
</script>
<script id="identity-frag" type="x-shader/x-fragment">
precision mediump float;

uniform sampler2D Texture;

varying vec4 texCoord0;
void main()
{
    vec4 c = texture2D(Texture, texCoord0.st);
    gl_FragColor = c;
}
</script>
<style>canvas{ position:absolute; }</style>
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<canvas id="gl" width="16" height="16"></canvas>
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