From 387a03c7eec8d51d0737888e7db6c835b46ac312 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Sun, 12 Dec 2021 00:22:07 +0100
Subject: [PATCH] - fixed triangulation via node builder for sectors with
 invalid walls.

The array indices were not properly adjusted for the missing elements an
---
 source/core/sectorgeometry.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/source/core/sectorgeometry.cpp b/source/core/sectorgeometry.cpp
index 4045f2a8b..40fad04d2 100644
--- a/source/core/sectorgeometry.cpp
+++ b/source/core/sectorgeometry.cpp
@@ -363,15 +363,17 @@ bool SectorGeometry::MakeVertices2(unsigned int secnum, int plane, const FVector
 		lines[j].wallnum = sline->wall;
 		lines[j].sidedef[0] = &sides[j];
 		lines[j].sidedef[1] = nullptr;
-		lines[j].v1 = &vertexes[i];
-		lines[j].v2 = &vertexes[sline->point2index];
+		lines[j].v1 = &vertexes[j];
+		lines[j].v2 = &vertexes[sline->point2index + j - i];
 
 		sides[j].sidenum = j;
 		sides[j].sector = sectorp;
 		j++;
 	}
-	lines.Resize(j);
-	sides.Resize(j);
+
+	vertexes.Clamp(j);
+	lines.Clamp(j);
+	sides.Clamp(j);
 	// Weed out any overlaps. These often happen with door setups and can lead to bad subsectors
 	for (unsigned i = 0; i < lines.Size(); i++)
 	{