OpenGL ES2.0 菲尼尔着色器

电玩女神 2022-06-01 06:28 224阅读 0赞

顶点着色器：

uniform mat4 uMVPMatrix; 		
    uniform mat4 uMMatrix; 			
    uniform vec3 uCamera;			
    attribute vec3 aPosition;  		
    attribute vec3 aNormal;    		
    varying vec3 eyeVary;			
    varying vec3 newNormalVary;		
    void main()  { 
      gl_Position = uMVPMatrix * vec4(aPosition,1); 
        vec3 normalTarget=aPosition+aNormal;
      vec3 newNormal=(uMMatrix*vec4(normalTarget,1)).xyz-(uMMatrix*vec4(aPosition,1)).xyz;
      newNormal=normalize(newNormal);  
      newNormalVary=newNormal;
        vec3 eye = normalize(uCamera-(uMMatrix*vec4(aPosition,1)).xyz);
      eyeVary=eye;
    }

片元着色器：

precision mediump float;
    uniform samplerCube sTexture;
    varying vec3 eyeVary;		
    varying vec3 newNormalVary;	
    vec4 zfs( 
      in float zsl
    ){  
      vec3 vTextureCoord;	
      vec4 finalColorZS;		
      vec4 finalColorFS;		
      vec4 finalColor;  		
      const float maxH=0.7;	
      const float minH=0.2;	
      float sizeH=maxH-minH;
      float testValue=abs(dot(eyeVary,newNormalVary));	
      if(testValue>maxH)  {							
         vTextureCoord=refract(-eyeVary,newNormalVary,zsl);
         finalColor=textureCube(sTexture, vTextureCoord);  
      }  else if(testValue<=maxH&&testValue>=minH) {
         vTextureCoord=reflect(-eyeVary,newNormalVary);
         finalColorFS=textureCube(sTexture, vTextureCoord);  	
         vTextureCoord=refract(-eyeVary,newNormalVary,zsl);
         finalColorZS=textureCube(sTexture, vTextureCoord);  	
         float ratio=(testValue-minH)/sizeH;					
         finalColor=finalColorZS*ratio+(1.0-ratio)*finalColorFS;	
      }  else   {										
         vTextureCoord=reflect(-eyeVary,newNormalVary);
         finalColor=textureCube(sTexture, vTextureCoord);  
      }  
      return finalColor;									
    }
    void main(){
       vec4 finalColor=vec4(0.0,0.0,0.0,0.0);
       finalColor.r=zfs(0.97).r;  		
       finalColor.g=zfs(0.955).g;  		
       finalColor.b=zfs(0.94).b;  		
       gl_FragColor=finalColor;}