From fd41361f6df5d175855260c7b55bf8205969762b Mon Sep 17 00:00:00 2001
From: biwa <6475593+biwa@users.noreply.github.com>
Date: Sat, 16 May 2020 13:22:33 +0200
Subject: [PATCH] Fixed an issue in Edit Selection Mode that could cause Out Of
 Memory exceptions with vertices that are slightly off grid in the 32 bit
 version

---
 Source/Plugins/BuilderModes/ClassicModes/EditSelectionMode.cs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Source/Plugins/BuilderModes/ClassicModes/EditSelectionMode.cs b/Source/Plugins/BuilderModes/ClassicModes/EditSelectionMode.cs
index 33551c6c..6cde59bb 100755
--- a/Source/Plugins/BuilderModes/ClassicModes/EditSelectionMode.cs
+++ b/Source/Plugins/BuilderModes/ClassicModes/EditSelectionMode.cs
@@ -1725,6 +1725,10 @@ namespace CodeImp.DoomBuilder.BuilderModes
 				//mxd. We'll need sidedefs marked by StitchGeometry, not all sidedefs from selection...
 				General.Map.Map.ClearMarkedSidedefs(false);
 
+				// Snap to map format accuracy. We need to do that before stitching geometry because vertices that are very very slightly off the grid (like 0.00001) can
+				// cause problems with BlockMapGetBlockCoordinates in the 32bit version
+				General.Map.Map.SnapAllToAccuracy(General.Map.UDMF && usepreciseposition);
+
 				// Stitch geometry
 				General.Map.Map.StitchGeometry(General.Settings.MergeGeometryMode);