From 77bed468a12f113a04058fee5b5df3381e82a995 Mon Sep 17 00:00:00 2001
From: sphere <spherallic@gmail.com>
Date: Mon, 25 Oct 2021 20:43:49 +0200
Subject: [PATCH] Visual Mode: Invert Lower Unpegged behavior for non-skewed
 FOFs to match SRB2.

---
 .../Plugins/BuilderModes/VisualModes/VisualMiddle3D.cs   | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/Source/Plugins/BuilderModes/VisualModes/VisualMiddle3D.cs b/Source/Plugins/BuilderModes/VisualModes/VisualMiddle3D.cs
index ffd963f..6dddb68 100644
--- a/Source/Plugins/BuilderModes/VisualModes/VisualMiddle3D.cs
+++ b/Source/Plugins/BuilderModes/VisualModes/VisualMiddle3D.cs
@@ -174,10 +174,11 @@ namespace CodeImp.DoomBuilder.BuilderModes
 
 			tlt.x = tlb.x = 0;
 			trt.x = trb.x = Sidedef.Line.Length;
-			tlt.y = IsLowerUnpegged() ? 0 : -(topheight - bottomheight);
-			trt.y = IsLowerUnpegged() ? 0 : -(topheight2 - bottomheight2);
-			tlb.y = !IsLowerUnpegged() ? 0 : (topheight - bottomheight);
-			trb.y = !IsLowerUnpegged() ? 0 : (topheight2 - bottomheight2);
+			// For SRB2, invert Lower Unpegged behavior for non-skewed 3D floors
+			tlt.y = !(IsLowerUnpegged() ^ skew) ? 0 : -(topheight - bottomheight);
+			trt.y = !(IsLowerUnpegged() ^ skew) ? 0 : -(topheight2 - bottomheight2);
+			tlb.y = !(!IsLowerUnpegged() ^ skew) ? 0 : (topheight - bottomheight);
+			trb.y = !(!IsLowerUnpegged() ^ skew) ? 0 : (topheight2 - bottomheight2);
 
 			// Apply texture offset
 			tlt += tof;