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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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<head>
<meta charset="utf-8">
<title>WebGL GLSL Conformance Tests</title>
<link rel="stylesheet" href="../../../resources/js-test-style.css"/>
<link rel="stylesheet" href="../../../resources/glsl-feature-tests.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="fragmentShader" type="text/something-not-javascript">
// fragment shader with for loop should succeed

// TODO(gman): trim to min size to test bug.
precision mediump float;
uniform float time;
uniform vec2 resolution;

// Saw-tooth function that is synced with the demo music (128bpm)
float gBeat;

// Calculate the surface color
vec3 surfColor(vec2 p)
{
    vec2 q=vec2(sin(.08*p.x),4.*p.y);
    vec3 c=vec3(0);
    for(float i=0.;i<15.;i++)
      c+=(1.+sin(i*sin(time)+vec3(0.,1.3,2.2)))*.2/length(q-vec2(sin(i),12.*sin(.3*time+i)));
    return c+vec3(mix(mod(floor(p.x*.2)+floor(p.y*2.2),2.),.2,gBeat));
}

// Ray trace (cylinder)
vec3 trace(vec3 o,vec3 d)
{
    d.y*=.65+.1*sin(.5*time);
    float D=1./(d.y*d.y+d.z*d.z),
          a=(o.y*d.y+o.z*d.z)*D,
          b=(o.y*o.y+o.z*o.z-36.)*D,
          t=-a-sqrt(a*a-b);
    o+=t*d;
    return surfColor(vec2(o.x,atan(o.y,o.z)))*(1.+.01*t);
}

void main()
{
    gBeat=fract(time*3.2/3.);
    // Screen setup
    vec2 p=(2.*gl_FragCoord.xy-resolution)/resolution.y,
         q=2.*gl_FragCoord.xy/resolution-1.;

    // Camera setup
    vec3 cp=vec3(-time*20.+1.,1.6*sin(time*1.2),2.+2.*cos(time*.3)),
         ct=cp+vec3(1.,.3*cos(time),-.2),
         cd=normalize(ct-cp),
         cr=normalize(cross(cd,vec3(.5*cos(.3*time),0.,1.))),
         cu=cross(cr,cd),
         rd=normalize(2.*cd+cr*p.x+cu*p.y);

    // Trace! (+some funky lens/raster effects)
    vec3 c=trace(cp,rd)*
           min(1.,1.8-dot(q,q))*
           (.9+.1*sin(3.*sin(gBeat)*gl_FragCoord.y));

    gl_FragColor=vec4(c,1);
}
</script>
<script>
"use strict";
GLSLConformanceTester.runTest();
var successfullyParsed = true;
</script>
</body>
</html>
