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

float4x4 worldmatrix;
float scale_factor;
float3 ldiffuse;
float3 lspecular;
float3 lattenuation;
float4 gambient;
float Ka;
float Kd;
float Ks;
sampler leaf: register(s0);
sampler shadowMap: register(s1);
sampler spotLight: register(s2);
sampler normalMap: register(s3);

float shadowBias = 45.57;
float backProjectionCut = 0.0;
float4 main_fp(float reg: VFACE, float3 normal: TEXCOORD0, float3 lightVec: TEXCOORD1, float3 viewVec: TEXCOORD2, float4 shadowCrd: TEXCOORD3, float4 texCoord: TEXCOORD4, float4 texCoordNormalized: TEXCOORD5) : COLOR
{
   float4 tempcolor;
   float4 ocolor;

   // The normals are not correct if we change the orientation of the impostor tree
   //----------------------------------------------------------------------------
   // Using normalmap
   //normal = tex2D(normalMap,texCoord);
   // If we have random orientations and not only 
   // the original normal_map tree orientation
   //normal = mul(worldmatrix,normal);
   // The values are from 0..255, so I should convert them from [0,255] to [0,1]
   // and convert from [0,1] to [-1,1]
   //normal = float3(1.0,1.0,1.0) - normalize(normal) * 2.0;
   //----------------------------------------------------------------------------

   // Front and Back faces lighted
   normal = (reg > 0.0) ? normal : -normal;

   // Radial distance
   float depth = length(lightVec);
   // Normalizes light vector
   lightVec /= depth;

   // Standard lighting
   float odiffuse = saturate(dot(lightVec, normal));
   float ospecular = pow(saturate(dot(reflect(-normalize(viewVec), normal), lightVec)), 16);

   // The depth of the fragment closest to the light
   float shadowMap = tex2Dproj(shadowMap, shadowCrd);
   // A spot image of the spotlight
   float spotLight = tex2Dproj(spotLight, shadowCrd);
   // If the depth is larger than the stored depth, this fragment
   // is not the closest to the light, that is we are in shadow.
   // Otherwise, we're lit. Add a bias to avoid precision issues
   float shadow;
   shadow = (depth < shadowMap + shadowBias);

   // Cut back-projection, that is, make sure we don't lit
   // anything behind the light. Theoretically, you should just
   // cut at w = 0, but in practice you'll have to cut at a
   // fairly high positive number to avoid precision issue when
   // coordinates approaches zero. 
   shadow *= (shadowCrd.w > backProjectionCut);
   // Modulate with spotlight image
   shadow *= spotLight;

   // Shadow any light contribution except ambient
   tempcolor = tex2D(leaf,texCoord);
   tempcolor = float4((Ka*(gambient.xyz)) + (Kd*(odiffuse * tempcolor.xyz * ldiffuse)) + (Ks * (ospecular * lspecular)),tempcolor.w);      
  
   // Shows each side the front and the back side...
   //tempcolor = (reg > 0.0) ? float4(1.0,0.0,0.0,tempcolor.w) : float4(0.0,1.0,0.0,tempcolor.w);
   
   // No lighting test...
   //tempcolor = tex2D(leaf,texCoord);
   ocolor = tempcolor;
   return  ocolor;
}