Fix shaders when far clip fading is active

core/src/main/java/com/seibel/distanthorizons/core/render/renderer/DhFadeRenderer.java

@@ -110,8 +110,6 @@ public class DhFadeRenderer
 	
 	public void render(Mat4f mcModelViewMatrix, Mat4f mcProjectionMatrix, float partialTicks, IProfilerWrapper profiler)
 	{
-		GLState mcState = new GLState();
-		
 		try
 		{
 			profiler.push("Fade Generate");
@@ -149,10 +147,6 @@ public class DhFadeRenderer
 		}
 		finally
 		{
-			// make sure we always revert to MC's state to prevent GL state corruption
-			// this is especially important on MC 1.16.5 or when other rendering mods are present
-			mcState.restore();
-			
 			profiler.pop();
 		}
 	}

core/src/main/java/com/seibel/distanthorizons/core/render/renderer/LodRenderer.java

@@ -243,7 +243,10 @@ public class LodRenderer
 			}
 			
 			// far plane clip fading
-			if (Config.Client.Advanced.Graphics.Quality.dhFadeFarClipPlane.get())
+			if (Config.Client.Advanced.Graphics.Quality.dhFadeFarClipPlane.get()
+				// the fade shader messes with the GL state in a way Iris doesn't like,
+				// so skip it if a shader is active
+				&& !IRIS_ACCESSOR.isShaderPackInUse())
 			{
 				profiler.popPush("Fade Far Clip Fade");
 				DhFadeRenderer.INSTANCE.render(