// This is C9E5v_projTex from "The Cg Tutorial" (Addison-Wesley, ISBN
// 0321194969) by Randima Fernando and Mark J. Kilgard.  See page 254.

void C9E5v_projTex(float4 position : POSITION,
                   float3 normal   : NORMAL,
       
               out float4 oPosition       : POSITION,
               out float4 texCoordProj    : TEXCOORD0,
               out float4 diffuseLighting : COLOR,
       
           uniform float Kd,
           uniform float4x4 modelViewProj,
           uniform float3   lightPosition, 
           uniform float4x4 textureMatrix)
{
  oPosition = mul(modelViewProj, position);

  // Compute texture coordinates for 
  // querying the projective texture
  texCoordProj = mul(textureMatrix, position);
  
  // Compute diffuse lighting
  float3 N = normalize(normal);
  float3 L = normalize(lightPosition - position.xyz);
  diffuseLighting = Kd * max(dot(N, L), 0);
}