Title:           [OpenGL Shading] lighting1.fsh
Author:          dajfarrell
Pastebin link:   http://pastebin.com/T8EFiX52
First Edit:      Saturday 9th of June 2012 07:14:56 AM CDT
Last Edit:       Saturday 9th of June 2012 07:14:56 AM CDT

#version 330
 
const int MAX_POINT_LIGHTS = 8;
 
struct PointLight {
    vec4 vLightPosition;
   
    vec3 vDiffuse;
    vec3 vAmbient;
    vec3 vSpecular;
   
    float fConstantAttenuation;
    float fLinearAttenuation;
    float fQuadraticAttenuation;
    float fCubicAttenuation;
    float fQuarticAttenuation;
};
 
uniform vec3 u_vGlobalAmbient;
uniform PointLight u_PointLights[MAX_POINT_LIGHTS];
 
in vec3 v_vNormal;
in vec4 v_vEyeCameraPosition;
 
out vec4 o_vFragColor;
 
void main() {
    vec3 vNormal = vec3(0.0, 0.0, 1.0);
    vec3 vColor = u_vGlobalAmbient;
   
    for(int i=0; i<2; ++i) {
        vec3 vAux = vec3(u_PointLights[i].vLightPosition - v_vEyeCameraPosition);
       
        vec3 vLightDir = normalize(vAux);
        float fDistance = length(vAux);
       
        vec3 vHalfVector = normalize(vLightDir - normalize(vec3(v_vEyeCameraPosition)));
       
        vec3 vInterpNormal = normalize(vNormal);
       
        float fNDotL = dot(vInterpNormal, vLightDir);
       
        if(fNDotL > 0.0) {
            float fAttenuation = 1.0 / (
                                        u_PointLights[i].fConstantAttenuation +
                                        u_PointLights[i].fLinearAttenuation * fDistance +
                                        u_PointLights[i].fQuadraticAttenuation * pow(fDistance, 2.0) +
                                        u_PointLights[i].fCubicAttenuation * pow(fDistance, 3.0) +
                                        u_PointLights[i].fQuarticAttenuation * pow(fDistance, 4.0));
           
            vColor += fAttenuation * (u_PointLights[i].vDiffuse * fNDotL + u_PointLights[i].vAmbient);
           
            float fNDotHV = max(0.0, dot(vInterpNormal, vHalfVector));
           
            vColor += fAttenuation * u_PointLights[i].vSpecular * pow(fNDotHV, 128.0);
        }
    }
   
    o_vFragColor = vec4(vColor, 1.0);
}