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C-/C++-Quelltext

uniform mat4 matView;
uniform mat3 matViewProjection;

uniform float fHeightScale;
uniform float fPerspectiveBias;
uniform vec4 vLightOffset;

varying vec2 TexCoord;
varying vec3 Normal;
varying vec3 Binormal;
varying vec3 Tangent;
varying vec3 EyeVector;
varying vec3 LightVector;
varying vec2 vParallaxXY;

attribute vec3 rm_Binormal;
attribute vec3 rm_Tangent;


void main(void)
{
    // Transform the position

    gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;

    // Set the texture coordinate

    TexCoord = gl_MultiTexCoord0.xy;

    // Compute the view vector in view space

    vec3 vView = -(matView * gl_Vertex);

    // Compute tangent space basis vector in view space

    vec3 vTangent = mat3(matView) * rm_Tangent;
    vec3 vBinormal = mat3(matView) * rm_Binormal;
    vec3 vNormal = mat3(matView) * Normal;

    // Normalize the view vector in tangent space

    vec3 vViewTS = mat3(vTangent, vBinormal, vNormal) * normalize(vView);

    // Compute initial parallax displacement direction

    vec2 vParallaxDirection = normalize(vViewTS.xy);

    // Compute the length of the parallax displacement vector

    float fParallaxLength = -sqrt(1.0 - vViewTS.z * vViewTS.z) / vViewTS.z;

    // Compute the parallax bias parameter

    float fParallaxBias = fPerspectiveBias + (1.0 - fPerspectiveBias) * (2.0 * vViewTS.z - 1.0);

    // Compute the actual reverse parallax displacement vector

    vParallaxXY = -vParallaxDirection * fParallaxLength * fParallaxBias * fHeightScale;

    // Compute light vector (view space):

    vec3 vLight = vView + vLightOffset;

    // Propagate the view and the light vectors (in tangent space):

    EyeVector = mat3(vTangent, vBinormal, vNormal) * vView;
    LightVector = mat3(vTangent, vBinormal, vNormal) * vLight;
}