attenuation!

res/shaders/simple.frag

@@ -18,10 +18,13 @@ float dither(vec2 uv) {
 
 const vec3 objectColor = vec3(1.0, 1.0, 1.0);
 const vec3 lightColor = vec3(0.5, 0.5, 0.5);
+
 const float ambientStrength = 0.1;
 const float specularStrength = 0.5;
 const float shininess = 32.0;
 
+const float la = 0.1, lb = 0.01, lc = 0.001;
+
 void main()
 {
     vec3 norm = normalize(normal);
@@ -31,7 +34,10 @@ void main()
     vec3 result = ambient;
 
     for (int i = 0; i < 3; i++) {
-        vec3 lightDir = normalize(lightPositions[i] - worldPositions);
+        vec3 lightVector = lightPositions[i] - worldPositions;
+        vec3 lightDir = normalize(lightVector);
+        float d = length(lightVector);
+        float attenuation = 1.0 / (la + d * lb + d * d * lc);
         float diff = max(dot(norm, lightDir), 0.0);
         vec3 diffuse = diff * lightColor;
 
@@ -39,7 +45,7 @@ void main()
         float spec = pow(max(dot(norm, halfwayDir), 0.0), shininess);
         vec3 specular = specularStrength * spec * lightColor;
 
-        result += (diffuse + specular) * objectColor;
+        result += attenuation * (diffuse + specular) * objectColor;
     }
 
     color = vec4(result, 1.0);