source: GTP/trunk/App/Demos/Illum/IBRBillboardCloudTrees/OGRE/IBRTreesOGRE/media/oldgeneral/depth_shadow_mapping_indirect_texturing_fp.shd @ 1493

float4 gambient;        
sampler textureAlpha: register(s0);
sampler leaf: register(s5);

float4 main(float3 normal:    TEXCOORD0,  float3 lightVec : TEXCOORD1,   float4 texCoord:  TEXCOORD2,  float4 texCoordNormalized: TEXCOORD3) : COLOR
{
   float depth = length(lightVec.xyz);

   if (tex2D(textureAlpha,texCoord).w > 0.0) 
   {
                
        return float4(gambient.xyz,depth);              
   }
   else
   {
        discard;
   }
}