shadow.sha

//Cg

void vshader(float4 vtx_position : POSITION,
             float2 vtx_texcoord0: TEXCOORD0,
             float3 vtx_normal: NORMAL,

             uniform float4x4 trans_model_to_clip_of_light,
             uniform float4x4 mat_modelproj,
             uniform float4 mspos_light,
             uniform float4 k_ambient,
             uniform float4 k_scale,
             uniform float4 k_push,

             out float4 l_position : POSITION,
             out float2 l_texcoord0 : TEXCOORD0,
             out float4 l_shadowcoord : TEXCOORD1,
         out float  l_smooth : TEXCOORD2,
         out float4 l_lightclip : TEXCOORD3
             )

{
float4 position = vtx_position * k_scale;

// vertex position
l_position = mul(mat_modelproj, position);

// Pass through texture coordinate for main texture.
l_texcoord0 = vtx_texcoord0;

// Calculate the surface lighting factor.
l_smooth = saturate(dot(vtx_normal, normalize(mspos_light - position)));

// Calculate light-space clip position.
float4 pushed = position + float4(vtx_normal * k_push, 0);
l_lightclip = mul(trans_model_to_clip_of_light, pushed);

// Calculate shadow-map texture coordinates.
l_shadowcoord = l_lightclip * float4(0.5,0.5,0.5,1.0) + l_lightclip.w * float4(0.5,0.5,0.5,0.0);
}


void fshader(in float2 l_texcoord0 : TEXCOORD0,
             in float4 l_shadowcoord : TEXCOORD1,
             in float  l_smooth : TEXCOORD2,
             in float4 l_lightclip : TEXCOORD3,
             uniform float4 attr_color,
             uniform sampler2D tex_0 : TEXUNIT0,
             uniform sampler2D k_Ldepthmap : TEXUNIT1,
             uniform float4 k_ambient,
         uniform float4 k_texDisable,
             out float4 o_color:COLOR)
{
  float3 circleoffs = float3(l_lightclip.xy / l_lightclip.w, 0);
  float falloff = saturate(1.0 - dot(circleoffs, circleoffs));
  float4 baseColor = saturate(tex2D(tex_0, l_texcoord0) + k_texDisable);
  float shade=tex2D(k_Ldepthmap, l_shadowcoord.xy/l_shadowcoord.w).x;
  shade=step((l_shadowcoord.z/l_shadowcoord.w), shade);
  /* The attr_color parameter is only necessary if you use/want to use
  vertex colors in your scene */
  o_color =  attr_color * baseColor * ( falloff * shade * l_smooth + k_ambient.x );
  o_color.a = attr_color.a;
}