From 6d41854ed2c5eccd412c0bb1269771080ce55dfd Mon Sep 17 00:00:00 2001
From: Kawe Mazidjatari <48657826+Mauler125@users.noreply.github.com>
Date: Thu, 17 Oct 2024 20:37:42 +0200
Subject: [PATCH] Recast: mark unconnected portal edges as boundary edges

We can utilize this edge to create traverse links, which only happen on boundary edges.
---
 src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp b/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
index 66ddaae1..91ba65a6 100644
--- a/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
+++ b/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
@@ -493,6 +493,14 @@ void dtNavMesh::connectExtLinks(dtMeshTile* tile, dtMeshTile* target, int side)
 			dtPolyRef nei[4];
 			float neia[4*2];
 			int nnei = findConnectingPolys(va,vb, target, rdOppositeTile(dir), nei,neia,4);
+
+			// If the portal edge has no neighbor, mark the edge as a boundary edge.
+			if (!nnei)
+			{
+				poly->neis[j] = 0;
+				continue;
+			}
+
 			for (int k = 0; k < nnei; ++k)
 			{
 				unsigned int idx = tile->allocLink();