
/*
** Copyright (c) 2012 The Khronos Group Inc.
**
** Permission is hereby granted, free of charge, to any person obtaining a
** copy of this software and/or associated documentation files (the
** "Materials"), to deal in the Materials without restriction, including
** without limitation the rights to use, copy, modify, merge, publish,
** distribute, sublicense, and/or sell copies of the Materials, and to
** permit persons to whom the Materials are furnished to do so, subject to
** the following conditions:
**
** The above copyright notice and this permission notice shall be included
** in all copies or substantial portions of the Materials.
**
** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
*/


attribute vec4 gtf_Vertex;
uniform mat4 gtf_ModelViewProjectionMatrix;
varying vec4 color;

// Function declarations.
ivec4 function(ivec4 par[3]);
bool is_all(const in ivec4 par, const in int value);
bool is_all(const in ivec4 array[3], const in ivec4 value);
void set_all(out ivec4 array[3], const in ivec4 value);

void main (void)
{
    ivec4 par[3];
    ivec4 ret = ivec4(0, 0, 0, 0);

    float gray = 0.0;

    // Initialize the entire array to 1.
    set_all(par, ivec4(1, 1, 1, 1));

    ret = function(par);

    // The parameter should remain unchanged by the function and the function should return 1.
    if(is_all(par, ivec4(1, 1, 1, 1)) && is_all(ret, 1))
    {
        gray = 1.0;
    }

    color = vec4(gray, gray, gray, 1.0);
    gl_Position = gtf_ModelViewProjectionMatrix * gtf_Vertex;
}

// Function definitions.
ivec4 function(ivec4 par[3])
{
    // Return the value of the array.
    if(is_all(par, ivec4(1, 1, 1, 1)))
    {
        // Test parameter qualifier (default is "in").
        set_all(par, ivec4(0, 0, 0, 0));

        return ivec4(1, 1, 1, 1);
    }
    else
        return ivec4(0, 0, 0, 0);
}

bool is_all(const in ivec4 par, const in int value)
{
    bool ret = true;

    if(par[0] != value)
        ret = false;
    if(par[1] != value)
        ret = false;
    if(par[2] != value)
        ret = false;
    if(par[3] != value)
        ret = false;

    return ret;
}

bool is_all(const in ivec4 array[3], const in ivec4 value)
{
    bool ret = true;

    if(array[0] != value)
        ret = false;
    if(array[1] != value)
        ret = false;
    if(array[2] != value)
        ret = false;

    return ret;
}

void set_all(out ivec4 array[3], const in ivec4 value)
{
    array[0] = value;
    array[1] = value;
    array[2] = value;
}
