From e57e85b88a8d8b9868e770fbcdbf0bc6302ca98e Mon Sep 17 00:00:00 2001
From: Kawe Mazidjatari <48657826+Mauler125@users.noreply.github.com>
Date: Thu, 18 Jul 2024 23:58:39 +0200
Subject: [PATCH] Recast: initial implementation of jump links for off-mesh
 links

These should set them up properly in theory. Needs testing.
---
 .../recast/Detour/Include/DetourNavMesh.h     |  2 ++
 .../recast/Detour/Source/DetourNavMesh.cpp    | 35 ++++++++++++-------
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/src/thirdparty/recast/Detour/Include/DetourNavMesh.h b/src/thirdparty/recast/Detour/Include/DetourNavMesh.h
index 8e6fd5ce..08fbd51f 100644
--- a/src/thirdparty/recast/Detour/Include/DetourNavMesh.h
+++ b/src/thirdparty/recast/Detour/Include/DetourNavMesh.h
@@ -274,6 +274,8 @@ struct dtLink
 	unsigned short reverseLink;		///< The reverse traversal link for this link. (Path returns through this link.)
 };
 
+unsigned char dtCalcLinkDistance(const float* spos, const float* epos);
+
 /// Bounding volume node.
 /// @note This structure is rarely if ever used by the end user.
 /// @see dtMeshTile
diff --git a/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp b/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
index 9aeb3de1..c30cdd9a 100644
--- a/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
+++ b/src/thirdparty/recast/Detour/Source/DetourNavMesh.cpp
@@ -213,9 +213,7 @@ dtNavMesh::dtNavMesh() :
 	m_polyBits = 0;
 #endif
 	memset(&m_params, 0, sizeof(dtNavMeshParams));
-	m_orig[0] = 0;
-	m_orig[1] = 0;
-	m_orig[2] = 0;
+	rdVset(m_orig, 0.0f,0.0f,0.0f);
 }
 
 dtNavMesh::~dtNavMesh() // TODO: see [r5apex_ds + F43720] to re-implement this correctly
@@ -526,7 +524,7 @@ void dtNavMesh::connectExtOffMeshLinks(dtMeshTile* tile, dtMeshTile* target, int
 		// Make sure the location is on current mesh.
 		float* v = &target->verts[targetPoly->verts[1]*3];
 		rdVcopy(v, nearestPt);
-				
+
 		// Link off-mesh connection to target poly.
 		unsigned int idx = allocLink(target);
 		dtLink* link = nullptr;
@@ -569,14 +567,22 @@ void dtNavMesh::connectExtOffMeshLinks(dtMeshTile* tile, dtMeshTile* target, int
 			}
 		}
 
-		// Set the reverse link indices if there is a possibility to reverse.
-		// NOTE: it appears that Titanfall 2 doesn't seem to do this on their
-		// navmeshes, so we probably shouldn't do it either. Commented for now.
-		//if (link && tlink)
-		//{
-		//	link->reverseLinkIndex = (unsigned short)tidx;
-		//	tlink->reverseLinkIndex = (unsigned short)idx;
-		//}
+		// NOTE: this might not be correct; Titanfall 2 off-mesh link dtLink
+		// objects don't set these, however when setting these, the jump links
+		// do work. More research is needed, this might also be correct, just
+		// not the way they are done originally.
+		if (link && tlink)
+		{
+			const unsigned char linkDist = dtCalcLinkDistance(&targetCon->pos[0], &targetCon->pos[3]);
+
+			link->traverseType = targetCon->jumpType;
+			link->traverseDist = linkDist;
+			link->reverseLink = (unsigned short)tidx;
+
+			tlink->traverseType = targetCon->jumpType;
+			tlink->traverseDist = linkDist;
+			tlink->reverseLink = (unsigned short)idx;
+		}
 	}
 }
 
@@ -1731,6 +1737,11 @@ dtStatus dtNavMesh::getPolyArea(dtPolyRef ref, unsigned char* resultArea) const
 	return DT_SUCCESS;
 }
 
+unsigned char dtCalcLinkDistance(const float* spos, const float* epos)
+{
+	return (unsigned char)rdVdist(spos, epos) / DT_TRAVERSE_DIST_QUANT_FACTOR;
+}
+
 float dtCalcPolySurfaceArea(const dtPoly* poly, const float* verts)
 {
 	float polyArea = 0.0f;