www.pudn.com > 3dwind2.0.rar > LightMaterial_ps.glsl

/******************************************************************************  
Copyright (c) W.J. van der Laan  
  
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******************************************************************************/  
/** Deferred shading framework  
	// W.J. :wumpus: van der Laan 2005 //  
	  
	Post shader: Light geometry material  
*/  
uniform sampler2D tex0;  
uniform sampler2D tex1;  
  
varying vec2 texCoord;  
varying vec3 projCoord;  
  
// World view matrix to get object position in view space  
uniform mat4 worldView;  
  
// Attributes of light  
uniform vec3 lightDiffuseColor;  
uniform vec3 lightSpecularColor;  
uniform vec3 lightFalloff;  
  
void main()  
{  
	vec4 a0 = texture2D(tex0, texCoord); // Attribute 0: Diffuse color+shininess  
    vec4 a1 = texture2D(tex1, texCoord); // Attribute 1: Normal+depth  
  
    // Attributes  
    vec3 colour = a0.rgb;  
    float alpha = a0.a;		// Specularity  
    float distance = a1.w;  // Distance from viewer (w)  
    vec3 normal = a1.xyz;  
  
	// Calculate position of texel in view space  
    vec3 position = projCoord*distance;  
	  
	// Extract position in view space from worldView matrix  
	//vec3 lightPos = vec3(worldView[0][3],worldView[1][3],worldView[2][3]);  
	vec3 lightPos = vec3(worldView[3][0],worldView[3][1],worldView[3][2]);  
	  
    // Calculate light direction and distance  
    vec3 lightVec = lightPos - position;  
    float len_sq = dot(lightVec, lightVec);  
    float len = sqrt(len_sq);  
    vec3 lightDir = lightVec/len;  
      
    /// Calculate attenuation      
    float attenuation = dot(lightFalloff, vec3(1, len, len_sq));  
      
    /// Calculate diffuse colour  
    vec3 light_diffuse = max(0.0,dot(lightDir, normal)) * lightDiffuseColor;  
      
    /// Calculate specular component  
    vec3 viewDir = -normalize(position);  
    vec3 h = normalize(viewDir + lightDir);  
    vec3 light_specular = pow(dot(normal, h),32.0) * lightSpecularColor;  
      
    // Calcalate total lighting for this fragment  
    vec3 total_light_contrib;  
    total_light_contrib = light_diffuse;  
	// Uncomment next line if specular desired  
	//total_light_contrib += alpha * light_specular;  
	  
    gl_FragColor = vec4(total_light_contrib*colour/attenuation, 0);  
    //gl_FragColor = vec4(1.0/attenuation, 0.0,0.0,0.0);  
    //gl_FragColor = vec4(a1.xyz,  0.0);  
}