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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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<head>
<meta charset="utf-8">
<title>GLSL 3.00 forward declaration 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>
<script src="../../js/glsl-conformance-test.js"></script>
</head>
<body>
<div id="description"></div>
<div id="console"></div>
<script id="vertexShaderForwardDecl" type="x-shader/x-vertex">#version 300 es
precision mediump float;

// Forward declaration. Breaks on Pixel C due to flattening of
// precision qualifiers. It seems the GLSL compiler can't handle the
// precision qualifier on the return value.
float identity(float val);

float identity(float val) {
  return val;
}

void main(void) {
    gl_Position = vec4(identity(1.0), 0.0, 0.0, 1.0);
}
</script>
<script id="vertexShader" type="x-shader/x-vertex">#version 300 es
void main(void) {
    gl_Position = vec4(1.0, 0.0, 0.0, 1.0);
}
</script>
<script id="fragmentShader" type="x-shader/x-fragment">#version 300 es
precision mediump float;

out vec4 my_FragColor;
void main(void) {
  my_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
}
</script>
<script id="fragmentShaderForwardDecl" type="x-shader/x-fragment">#version 300 es
precision mediump float;

// Forward declaration. Breaks on Pixel C due to flattening of
// precision qualifiers. It seems the GLSL compiler can't handle the
// precision qualifier on the return value.
float identity(float val);

float identity(float val) {
  return val;
}

out vec4 my_FragColor;
void main(void) {
  my_FragColor = vec4(0.0, identity(1.0), 0.0, 1.0);
}
</script>
<script type="application/javascript">
"use strict";
description("Forward declarations of functions should succeed.");

GLSLConformanceTester.runTests([
  {
    vShaderId: "vertexShaderForwardDecl",
    vShaderSuccess: true,
    fShaderId: "fragmentShader",
    fShaderSuccess: true,
    linkSuccess: true,
    passMsg: "vertex shader with forward declaration must pass",
  },
  {
    vShaderId: "vertexShader",
    vShaderSuccess: true,
    fShaderId: "fragmentShaderForwardDecl",
    fShaderSuccess: true,
    linkSuccess: true,
    passMsg: "fragment shader with forward declaration must pass",
  },
], 2);
</script>
</body>
</html>
