source: code/trunk/Tutorial/Media/DeferredShadingMedia/DeferredShading/post/glsl/vs.glsl @ 44

/******************************************************************************
Copyright (c) W.J. van der Laan

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******************************************************************************/
/** Deferred shading framework
        // W.J. :wumpus: van der Laan 2005 //
        
        Post shader: Generic fullscreen quad
*/
varying vec2 texCoord;
varying vec3 projCoord;

uniform mat4 invProj;

void main()                    
{
        vec2 inPos = sign(gl_Vertex.xy);
        gl_Position = vec4(inPos.xy, 0.0, 1.0);
        
        texCoord  = (vec2(inPos.x, -inPos.y) + 1.0)/2.0;
   
        // Projection coordinates
        // Inverted projection matrix
        // These interpolate over the frustrum plane for w=1
    projCoord = vec3(invProj*vec4(inPos.x, inPos.y, 0, 1));
}