diff --git a/src/gl/scene/gl_portal.cpp b/src/gl/scene/gl_portal.cpp
index 9b86cbbe8bd..3f8ede410a5 100644
--- a/src/gl/scene/gl_portal.cpp
+++ b/src/gl/scene/gl_portal.cpp
@@ -874,6 +874,8 @@ void GLMirrorPortal::DrawContents(FDrawInfo *di)
 		return;
 	}
 
+	di->UpdateCurrentMapSection();
+
 	di->mClipPortal = this;
 	DAngle StartAngle = r_viewpoint.Angles.Yaw;
 	DVector3 StartPos = r_viewpoint.Pos;
@@ -943,8 +945,6 @@ void GLMirrorPortal::DrawContents(FDrawInfo *di)
 	angle_t a1 = linedef->v2->GetClipAngle();
 	di->mClipper->SafeAddClipRange(a1,a2);
 
-	di->UpdateCurrentMapSection();
-
 	gl_RenderState.SetClipLine(linedef);
 	gl_RenderState.EnableClipLine(true);
 	drawer->DrawScene(di, DM_PORTAL);