From 5500e99ed8af01e6ef927db5c5f78c3ea1722379 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Thu, 31 Aug 2023 09:37:27 +0200
Subject: [PATCH] Add `NavMeshPathFlags` to navmesh for partial paths info

---
 Source/Engine/Navigation/NavMeshRuntime.cpp |  4 ++-
 Source/Engine/Navigation/NavMeshRuntime.h   | 29 ++++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/Source/Engine/Navigation/NavMeshRuntime.cpp b/Source/Engine/Navigation/NavMeshRuntime.cpp
index b09f8346a..913c46e3e 100644
--- a/Source/Engine/Navigation/NavMeshRuntime.cpp
+++ b/Source/Engine/Navigation/NavMeshRuntime.cpp
@@ -78,9 +78,10 @@ bool NavMeshRuntime::FindDistanceToWall(const Vector3& startPosition, NavMeshHit
     return true;
 }
 
-bool NavMeshRuntime::FindPath(const Vector3& startPosition, const Vector3& endPosition, Array<Vector3, HeapAllocation>& resultPath) const
+bool NavMeshRuntime::FindPath(const Vector3& startPosition, const Vector3& endPosition, Array<Vector3, HeapAllocation>& resultPath, NavMeshPathFlags& resultFlags) const
 {
     resultPath.Clear();
+    resultFlags = NavMeshPathFlags::None;
     ScopeLock lock(Locker);
     const auto query = GetNavMeshQuery();
     if (!query || !_navMesh)
@@ -120,6 +121,7 @@ bool NavMeshRuntime::FindPath(const Vector3& startPosition, const Vector3& endPo
 
     if (pathSize == 1 && dtStatusDetail(findPathStatus, DT_PARTIAL_RESULT))
     {
+        resultFlags |= NavMeshPathFlags::PartialPath;
         // TODO: skip adding 2nd end point if it's not reachable (use navmesh raycast check? or physics check? or local Z distance check?)
         resultPath.Resize(2);
         resultPath[0] = startPosition;
diff --git a/Source/Engine/Navigation/NavMeshRuntime.h b/Source/Engine/Navigation/NavMeshRuntime.h
index 2183ca6f2..6070ec0e1 100644
--- a/Source/Engine/Navigation/NavMeshRuntime.h
+++ b/Source/Engine/Navigation/NavMeshRuntime.h
@@ -24,6 +24,19 @@ public:
     BytesContainer Data;
 };
 
+/// <summary>
+/// The navigation mesh path flags.
+/// </summary>
+enum class NavMeshPathFlags
+{
+    // Nothing.
+    None = 0,
+    // Path is only partially generated, goal is unreachable so path represents the best guess.
+    PartialPath = 1,
+};
+
+DECLARE_ENUM_OPERATORS(NavMeshPathFlags);
+
 /// <summary>
 /// The navigation mesh runtime object that builds the navmesh from all loaded scenes.
 /// </summary>
@@ -106,7 +119,21 @@ public:
     /// <param name="endPosition">The end position.</param>
     /// <param name="resultPath">The result path.</param>
     /// <returns>True if found valid path between given two points (it may be partial), otherwise false if failed.</returns>
-    bool FindPath(const Vector3& startPosition, const Vector3& endPosition, Array<Vector3, HeapAllocation>& resultPath) const;
+    bool FindPath(const Vector3& startPosition, const Vector3& endPosition, Array<Vector3, HeapAllocation>& resultPath) const
+    {
+        NavMeshPathFlags flags;
+        return FindPath(startPosition, endPosition, resultPath, flags);
+    }
+
+    /// <summary>
+    /// Finds the path between the two positions presented as a list of waypoints stored in the corners array.
+    /// </summary>
+    /// <param name="startPosition">The start position.</param>
+    /// <param name="endPosition">The end position.</param>
+    /// <param name="resultPath">The result path.</param>
+    /// <param name="resultPath">The result path flags.</param>
+    /// <returns>True if found valid path between given two points (it may be partial), otherwise false if failed.</returns>
+    bool FindPath(const Vector3& startPosition, const Vector3& endPosition, Array<Vector3, HeapAllocation>& resultPath, NavMeshPathFlags& resultFlags) const;
 
     /// <summary>
     /// Tests the path between the two positions (non-partial).