- fixed: The depth clamp setting needs to be tracked per portal so that it can be properly restored afterward.

Regular skies need it off but SkyViewpoints need it on - and all others need to use the parent's setting.
So without engine side tracking we can end up rendering the sky with this setting off, resulting in omission of the fog layer.

src/gl/renderer/gl_renderstate.cpp

@@ -90,6 +90,7 @@ void FRenderState::Reset()
 	stSrcBlend = stDstBlend = -1;
 	stBlendEquation = -1;
 	stAlphaThreshold = -1.f;
+	mLastDepthClamp = true;
 }
 
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