Merged in davep/BUG-228263 (pull request #25)

Fix for mismatch on angular attenuation between sunlight on opaque and transparent objects from last commit.

indra/newview/app_settings/shaders/class1/deferred/alphaF.glsl

@@ -223,6 +223,7 @@ void main()
 
     float da = dot(norm.xyz, light_dir.xyz);
           da = clamp(da, -1.0, 1.0);
+          da = pow(da, 1.0/1.3);
  
     float final_da = da;
           final_da = clamp(final_da, 0.0f, 1.0f);
@@ -231,7 +232,7 @@ void main()
 
     color.a   = final_alpha;
 
-    float ambient = da;
+    float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);
     ambient *= 0.5;
     ambient *= ambient;
     ambient = (1.0 - ambient);

indra/newview/app_settings/shaders/class1/deferred/materialF.glsl

@@ -331,8 +331,9 @@ void main()
         vec3 refnormpersp = normalize(reflect(pos.xyz, norm));
 
         float da = clamp(dot(normalize(norm.xyz), light_dir.xyz), 0.0, 1.0);
+        da = pow(da, 1.0/1.3);
 
-        float ambient = da;
+        float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);
         ambient *= 0.5;
         ambient *= ambient;
         ambient = (1.0 - ambient);