SL-9996

Force frag depth in water shaders to avoid z-fighting at back edge of water edge pieces.

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

@@ -167,7 +167,10 @@ void main()
 	color.a   = spec * sunAngle2;
 
 	vec3 screenspacewavef = normalize((norm_mat*vec4(wavef, 1.0)).xyz);
-	
+
+    // force frag depth which doesn't z-fight
+    gl_FragDepth = 0.99999f;	
+
 	frag_data[0] = vec4(color.rgb, color); // diffuse
 	frag_data[1] = vec4(0);		// speccolor, spec
 	frag_data[2] = vec4(encode_normal(screenspacewavef.xyz*0.5+0.5), 0.05, 0);// normalxy, 0, 0

indra/newview/app_settings/shaders/class1/environment/waterF.glsl

@@ -157,5 +157,7 @@ void main()
 	color.rgb = scaleSoftClip(color.rgb);
 	color.a = spec * sunAngle2;
 
+    // force frag depth to fix z-fighting at back edge of water edge pieces
+    gl_FragDepth = 0.99999;
 	frag_color = color;
 }