SL-20611 Followup -- fix for depth based atmospheric mask making atmospherics effect sun/moon/clouds

indra/newview/app_settings/shaders/class3/deferred/hazeF.glsl

@@ -78,13 +78,12 @@ void main()
         do_atmospherics = true;
     }
     
-
     vec3  irradiance = vec3(0);
     vec3  radiance  = vec3(0);
 
     if (depth >= 1.0)
     {
-        //should only be true of WL sky, just port over base color value
+        //should only be true of sky, clouds, sun/moon, and stars
         discard;
     }
 

indra/newview/lldrawpool.h

@@ -53,7 +53,9 @@ public:
         // before grass, so grass should be the first alpha masked pool.  Other ordering should be done
         // based on fill rate and likelihood to occlude future passes (faster, large occluders first).
         //  
-		POOL_SIMPLE = 1,
+        POOL_SKY = 1,
+        POOL_WL_SKY,
+		POOL_SIMPLE,
 		POOL_FULLBRIGHT,
 		POOL_BUMP,
 		POOL_TERRAIN,
@@ -64,8 +66,6 @@ public:
 		POOL_TREE,
 		POOL_ALPHA_MASK,
 		POOL_FULLBRIGHT_ALPHA_MASK,
-        POOL_SKY,
-        POOL_WL_SKY,
 		POOL_AVATAR,
 		POOL_CONTROL_AV, // Animesh
 		POOL_GLOW,

indra/newview/lldrawpoolwlsky.cpp

@@ -87,6 +87,9 @@ void LLDrawPoolWLSky::endDeferredPass(S32 pass)
     cloud_shader = nullptr;
     sun_shader   = nullptr;
     moon_shader  = nullptr;
+
+    // clear the depth buffer so haze shaders can use unwritten depth as a mask
+    glClear(GL_DEPTH_BUFFER_BIT);
 }
 
 void LLDrawPoolWLSky::renderDome(const LLVector3& camPosLocal, F32 camHeightLocal, LLGLSLShader * shader) const