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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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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>GLSL short-circuiting operators should be evaluated after previous operands in a sequence</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>
<canvas id="canvas" width="64" height="64"> </canvas>
<div id="description"></div>
<div id="console"></div>
<script id="fshaderSequenceSideEffectsAffectTernary" type="x-shader/x-fragment">
precision mediump float;

bool correct = true;

uniform float u_zero;

float wrong() {
    correct = false;
    return 0.0;
}

void main() {
    // ESSL 1.00 section 5.9, about sequence operator:
    // "All expressions are evaluated, in order, from left to right"
    // Also use a ternary operator where the third operand has side effects to make sure
    // only the second operand is evaluated.
    float a = u_zero - 0.5; // Result should be -0.5.
    float green = (a++, a > 0.0 ? 1.0 : wrong());
    gl_FragColor = vec4(0.0, correct ? green : 0.0, 0.0, 1.0);
}
</script>
<script id="fshaderSequenceSideEffectsAffectAnd" type="x-shader/x-fragment">
precision mediump float;

uniform bool u_false;

bool sideEffectA = false;
bool funcA() {
    sideEffectA = true;
    return true;
}

bool sideEffectB = false;
bool funcB() {
    sideEffectB = true;
    return true;
}

void main() {
    bool b = (funcA(), u_false == sideEffectA && funcB());
    gl_FragColor = (!b && sideEffectA && !sideEffectB) ? vec4(0, 1, 0, 1) : vec4(1, 0, 0, 1);
}
</script>
<script id="fshaderSequenceSideEffectsAffectOr" type="x-shader/x-fragment">
precision mediump float;

uniform bool u_false;

bool sideEffectA = false;
bool funcA() {
    sideEffectA = true;
    return false;
}

bool sideEffectB = false;
bool funcB() {
    sideEffectB = true;
    return false;
}

void main() {
    bool b = (funcA(), (u_false == !sideEffectA) || funcB());
    gl_FragColor = (b && sideEffectA && !sideEffectB) ? vec4(0, 1, 0, 1) : vec4(1, 0, 0, 1);
}
</script>
<script type="application/javascript">
"use strict";
description();
debug("");
debug("This test is targeted to stress syntax tree transformations that might need to be done in shader translation to unfold operators.");

GLSLConformanceTester.runRenderTests([
{
  fShaderId: 'fshaderSequenceSideEffectsAffectTernary',
  fShaderSuccess: true,
  linkSuccess: true,
  passMsg: 'Expression where first operand of a sequence operator has side effects which affect the second operand that is a ternary operator'
},
{
  fShaderId: 'fshaderSequenceSideEffectsAffectAnd',
  fShaderSuccess: true,
  linkSuccess: true,
  passMsg: 'Expression where first operand of a sequence operator has side effects which affect the second operand that is an and operator'
},
{
  fShaderId: 'fshaderSequenceSideEffectsAffectOr',
  fShaderSuccess: true,
  linkSuccess: true,
  passMsg: 'Expression where first operand of a sequence operator has side effects which affect the second operand that is an or operator'
}
]);
</script>
</body>
</html>

