Merged in 559-impostor-fixes (pull request #1122)

Fix impostor lighting and rendering after PBR changes to rendering pipeline

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

@@ -41,6 +41,7 @@ uniform sampler2D specularMap;
 VARYING vec2 vary_texcoord0;
 
 vec3 linear_to_srgb(vec3 c);
+vec2 encode_normal (vec3 n);
 
 void main() 
 {
@@ -56,5 +57,5 @@ void main()
 
 	frag_data[0] = vec4(col.rgb, 0.0);
 	frag_data[1] = spec;
-	frag_data[2] = norm; // TODO: Should .w be set?
+	frag_data[2] = vec4(encode_normal(norm.xyz),0,GBUFFER_FLAG_HAS_ATMOS);
 }