SL-11589

Modify altitude blend factor in cloud shaders to fade more aggressively and fix cloud rendering artifacts when at altitude.

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

@@ -78,7 +78,7 @@ void main()
 	// Get relative position
 	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
 
-    altitude_blend_factor = (P.y > -4096.0) ? 1.0 : 1.0 - clamp(abs(P.y) / max_y, 0.0, 1.0);
+    altitude_blend_factor = clamp((P.y + 512.0) / max_y, 0.0, 1.0);
 
 	// Set altitude
 	if (P.y > 0.)

indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl

@@ -78,7 +78,7 @@ void main()
 	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
 
     // fade clouds beyond a certain point so the bottom of the sky dome doesn't look silly at high altitude
-    altitude_blend_factor = (P.y > -4096.0) ? 1.0 : 1.0 - clamp(abs(P.y) / max_y, 0.0, 1.0);
+    altitude_blend_factor = clamp((P.y + 512.0) / max_y, 0.0, 1.0);
 
 	// Set altitude
 	if (P.y > 0.)