学步园

struct output
{
      float4 position  : POSITION;    
      float3 objectPos : TEXCOORD0;   
      float3 normal     : TEXCOORD1;
};
 
output vs_main( float4 position : POSITION,
                  float3 normal   : NORMAL,
                  uniform float4x4 MV,
                  uniform float4x4 MVP
                    )
{
      output OUT;
      OUT.position = mul(MVP, position);
      OUT.objectPos = mul(MV, position).xyz;
      OUT.normal = mul(MV, float4(normal,0.0)).xyz;
 
      return OUT;
}

uniform float3 LightPosition;
uniform float3 eyePosition;
uniform float3 I;
uniform float3 Ka;
uniform float3 Kd;
uniform float3 Ks;
uniform float shininess;
 
struct input{
      float3 objectPos: TEXCOORD0;   
      float3 normal   : TEXCOORD1;
};
 
struct output{
      float4 color     : COLOR;
};
 
output fs_main( in input IN )
{
      output OUT;
 
      float3 N = normalize(IN.normal);
      float3 P = IN.objectPos;
 
      float3 L = normalize(LightPosition - P);
      float NdotL = max(dot(N,L),0);
 
      float3 ambient = Ka * I;
      float3 diffuse = Kd * I * NdotL;
 
      float3 V = normalize(eyePosition - P);
      float3 H = normalize(L+V);
      float NdotH = pow(max(dot(N,H), 0), shininess);
 
      if(NdotL<=0)
           NdotH = 0.0;
      float3 specular = Ks*I*NdotH;
 
      float3 color = ambient + diffuse + specular;
      OUT.color.xyz= color;
      OUT.color.w = 1.0;
 
      return OUT;
}