source: downloads/Samples/Media/DeferredShadingMedia/DeferredShading/material/glsl/nm_ps.glsl @ 1

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Copyright (c) W.J. van der Laan

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/** Deferred shading framework
        // W.J. :wumpus: van der Laan 2005 //
        
        Material shader: Textured normal mapped
*/

#extension GL_ARB_draw_buffers : enable

varying vec3 normal;
varying vec3 tangent_;
varying vec3 binormal;

varying vec2 texCoord0;
varying float depth;
uniform sampler2D tex0;
uniform sampler2D normTex;

uniform float specularity;

void main()                    
{
        // Frame for normal mapping
        mat3 rotation = mat3(tangent_, binormal, normal);
        vec3 texnormal = (vec3(texture2D(normTex, texCoord0))-0.5)*2.0;
        
        gl_FragData[0].rgb = vec3(texture2D(tex0, texCoord0));
        gl_FragData[0].a = specularity;
        // rotation*texnormal is reversed for GL because matrices are stored transposed internally
        // compared to HLSL
        gl_FragData[1].xyz = normalize(rotation*texnormal); // Do normalisation here, saves an operation per light
        gl_FragData[1].w = depth;
}