opengl.shaders: Use unified lighting and texturing 'snippets' for fragment shaders.

3-mid/opengl/assets/shader/lit_textured.frag

@@ -1,98 +1,18 @@
 // Include 'version.header'.
-// Include 'texturing.frag'.
-
-
-struct light
-{
-   vec4    Site;
-   vec3    Color;
-   float   Attenuation;
-   float   ambient_Coefficient;
-   float   cone_Angle;
-   vec3    cone_Direction;
-};
-
-
-uniform mat4        model_Transform;
-uniform mat3        inverse_model_Rotation;
-uniform vec3        camera_Site;
-uniform vec3        specular_Color;    // The materials specular color.
-
-uniform int         light_Count;
-uniform light       Lights [50];
-
-
-in  vec3   frag_Site;
-in  vec3   frag_Normal;
-in  vec2   frag_Coords;
-in  float  frag_Shine;
-
-out vec4   final_Color;
+// Include 'texturing-frag.snippet'.
+// Include 'lighting-frag.snippet'
 
 
 
+in  vec3       frag_Site;
+in  vec3       frag_Normal;
+in  vec2       frag_Coords;
 
-vec3
-apply_Light (light   Light, 
-             vec3    surface_Color, 
-             vec3    Normal, 
-             vec3    surface_Site, 
-             vec3    Surface_to_Camera)
-{
-    vec3    Surface_to_Light;
-    float   Attenuation = 1.0;
-    
-    if (Light.Site.w == 0.0)
-    {
-        // Directional light.
-        //
-        Surface_to_Light = normalize (-Light.Site.xyz);
-        Attenuation      = 1.0;     // No attenuation for directional lights.
-    } 
-    else
-    {
-        // Point light.
-        //
-        vec3    Surface_to_Light_vector = Light.Site.xyz - surface_Site;
-        float   Distance_to_Light       = length (Surface_to_Light_vector);
-
-        Surface_to_Light = normalize (Surface_to_Light_vector);
-        Attenuation      =   1.0
-                           / (  1.0 
-                              +   Light.Attenuation
-                                * pow (Distance_to_Light, 2));
-
-        // Cone restrictions which affects attenuation.
-        //
-        float   Light_to_Surface_Angle = degrees (acos (dot (-Surface_to_Light, 
-                                                             normalize (Light.cone_Direction))));
-        
-        if (Light_to_Surface_Angle > Light.cone_Angle)
-        {
-            Attenuation = 0.0;
-        }
-    }
-
-    vec3    lit_surface_Color    = surface_Color * Light.Color;
-    vec3    Ambient              = Light.ambient_Coefficient * lit_surface_Color;
-    float   diffuse_Coefficient  = max (0.0, 
-                                        dot (Normal,
-                                             Surface_to_Light));                   
-    vec3    Diffuse              = diffuse_Coefficient * lit_surface_Color;
-    float   specular_Coefficient = 0.0;
-
-    if (diffuse_Coefficient > 0.0)
-        specular_Coefficient = pow (max (0.0, 
-                                         dot (Surface_to_Camera, 
-                                              reflect (-Surface_to_Light,
-                                                       Normal))),
-                                    frag_Shine);
-
-    vec3   Specular = specular_Coefficient * specular_Color * Light.Color;
-
-    return Ambient + Attenuation * (Diffuse + Specular);     // Linear color (before gamma correction).
-}
+uniform mat4   model_Transform;
+uniform mat3   inverse_model_Rotation;
+uniform vec3   camera_Site;
 
+out vec4       final_Color;
 
 
 
@@ -118,8 +38,12 @@ main()
                                      Surface_to_Camera);
     }
     
-    vec3  Gamma = vec3 (1.0 / 2.2);
+    vec3   Gamma = vec3 (1.0 / 2.2);
+    
     final_Color = vec4 (pow (linear_Color,     // Final color (after gamma correction).
                              Gamma),
                         surface_Color.a);
+                        
+    final_Color = min (final_Color,            // Prevent light saturation.
+                       surface_Color);
 }