simple.frag

java 3d编程的一些例子源代码

/*
 * $RCSfile: simple.frag,v $
 *
 * Copyright (c) 2006 Sun Microsystems, Inc. All rights reserved.
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 *
 * This software is provided "AS IS," without a warranty of any
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 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
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 * $Revision: 1.1 $
 * $Date: 2006/02/01 01:32:40 $
 * $State: Exp $
 */

// Simple GLSL fragment program to attenuate the input fragment color as a
// function of the distance of the fragment position from the center
// of the window

const float windowSize = 700.0; // TODO: this should be a built-in parameter!

void main()
{
    // Compute distance from center in range [0.0, 1.0]
    vec2 dist = min(abs((gl_FragCoord.xy - (windowSize)/2.0) / windowSize), 1.0);
    vec2 invDist = 1.0 - dist;

    // Compute attenuation
    float atten = invDist.x * invDist.y;
    vec4 outcolor = (gl_Color + gl_SecondaryColor) * atten;

    gl_FragColor = outcolor;
}