Core/PathGenerator: Fix path generator returning shortcuts when start and end are on the same polygon (#24083)

* Core/PathGenerator: Fix path generator returning shortcuts when start and end are on the same polygon

Second try of handling paths on same poly in a better way than just building a shortcut

* Fix movement generators using paths with start/end positions far from mmap polygons

* Include flag PATHFIND_FARFROMPOLY even with a normal path if start or end were far away from mmap poly

src/server/game/Movement/MovementGenerators/ConfusedMovementGenerator.cpp

@@ -81,7 +81,9 @@ bool ConfusedMovementGenerator<T>::DoUpdate(T* owner, uint32 diff)
 
         _path->SetPathLengthLimit(30.0f);
         bool result = _path->CalculatePath(destination.GetPositionX(), destination.GetPositionY(), destination.GetPositionZ());
-        if (!result || (_path->GetPathType() & PATHFIND_NOPATH) || (_path->GetPathType() & PATHFIND_SHORTCUT))
+        if (!result || (_path->GetPathType() & PATHFIND_NOPATH)
+            || (_path->GetPathType() & PATHFIND_SHORTCUT)
+            || (_path->GetPathType() & PATHFIND_FARFROMPOLY))
         {
             _timer.Reset(100);
             return true;

src/server/game/Movement/MovementGenerators/FleeingMovementGenerator.cpp

@@ -126,7 +126,9 @@ void FleeingMovementGenerator<T>::SetTargetLocation(T* owner)
 
     _path->SetPathLengthLimit(30.0f);
     bool result = _path->CalculatePath(destination.GetPositionX(), destination.GetPositionY(), destination.GetPositionZ());
-    if (!result || (_path->GetPathType() & PATHFIND_NOPATH) || (_path->GetPathType() & PATHFIND_SHORTCUT))
+    if (!result || (_path->GetPathType() & PATHFIND_NOPATH)
+        || (_path->GetPathType() & PATHFIND_SHORTCUT)
+        || (_path->GetPathType() & PATHFIND_FARFROMPOLY))
     {
         _timer.Reset(100);
         return;

src/server/game/Movement/MovementGenerators/RandomMovementGenerator.cpp

@@ -123,7 +123,9 @@ void RandomMovementGenerator<Creature>::SetRandomLocation(Creature* owner)
 
     _path->SetPathLengthLimit(30.0f);
     bool result = _path->CalculatePath(position.GetPositionX(), position.GetPositionY(), position.GetPositionZ());
-    if (!result || (_path->GetPathType() & PATHFIND_NOPATH) || (_path->GetPathType() & PATHFIND_SHORTCUT))
+    if (!result || (_path->GetPathType() & PATHFIND_NOPATH)
+        || (_path->GetPathType() & PATHFIND_SHORTCUT)
+        || (_path->GetPathType() & PATHFIND_FARFROMPOLY))
     {
         _timer.Reset(100);
         return;

src/server/game/Movement/PathGenerator.cpp

@@ -227,7 +227,7 @@ void PathGenerator::BuildPolyPath(G3D::Vector3 const& startPos, G3D::Vector3 con
         if (buildShotrcut)
         {
             BuildShortcut();
-            _type = PathType(PATHFIND_NORMAL | PATHFIND_NOT_USING_PATH);
+            _type = PathType(PATHFIND_NORMAL | PATHFIND_NOT_USING_PATH | PATHFIND_FARFROMPOLY);
             return;
         }
         else
@@ -240,7 +240,7 @@ void PathGenerator::BuildPolyPath(G3D::Vector3 const& startPos, G3D::Vector3 con
                 SetActualEndPosition(G3D::Vector3(endPoint[2], endPoint[0], endPoint[1]));
             }
 
-            _type = PATHFIND_INCOMPLETE;
+            _type = PathType(PATHFIND_INCOMPLETE | PATHFIND_FARFROMPOLY);
         }
     }
 
@@ -252,13 +252,12 @@ void PathGenerator::BuildPolyPath(G3D::Vector3 const& startPos, G3D::Vector3 con
     {
         TC_LOG_DEBUG("maps.mmaps", "++ BuildPolyPath :: (startPoly == endPoly)");
 
-        BuildShortcut();
-
         _pathPolyRefs[0] = startPoly;
         _polyLength = 1;
 
-        _type = farFromPoly ? PATHFIND_INCOMPLETE : PATHFIND_NORMAL;
-        TC_LOG_DEBUG("maps.mmaps", "++ BuildPolyPath :: path type %d", _type);
+        _type = farFromPoly ? PathType(PATHFIND_INCOMPLETE | PATHFIND_FARFROMPOLY) : PATHFIND_NORMAL;
+
+        BuildPointPath(startPoint, endPoint);
         return;
     }
 
@@ -485,6 +484,9 @@ void PathGenerator::BuildPolyPath(G3D::Vector3 const& startPos, G3D::Vector3 con
     else
         _type = PATHFIND_INCOMPLETE;
 
+    if (farFromPoly)
+        _type = PathType(_type | PATHFIND_FARFROMPOLY);
+
     // generate the point-path out of our up-to-date poly-path
     BuildPointPath(startPoint, endPoint);
 }
@@ -791,11 +793,22 @@ dtStatus PathGenerator::FindSmoothPath(float const* startPos, float const* endPo
     uint32 npolys = polyPathSize;
 
     float iterPos[VERTEX_SIZE], targetPos[VERTEX_SIZE];
-    if (dtStatusFailed(_navMeshQuery->closestPointOnPolyBoundary(polys[0], startPos, iterPos)))
-        return DT_FAILURE;
 
-    if (dtStatusFailed(_navMeshQuery->closestPointOnPolyBoundary(polys[npolys-1], endPos, targetPos)))
-        return DT_FAILURE;
+    if (polyPathSize > 1)
+    {
+        // Pick the closest poitns on poly border
+        if (dtStatusFailed(_navMeshQuery->closestPointOnPolyBoundary(polys[0], startPos, iterPos)))
+            return DT_FAILURE;
+
+        if (dtStatusFailed(_navMeshQuery->closestPointOnPolyBoundary(polys[npolys - 1], endPos, targetPos)))
+            return DT_FAILURE;
+    }
+    else
+    {
+        // Case where the path is on the same poly
+        dtVcopy(iterPos, startPos);
+        dtVcopy(targetPos, endPos);
+    }
 
     dtVcopy(&smoothPath[nsmoothPath*VERTEX_SIZE], iterPos);
     nsmoothPath++;

src/server/game/Movement/PathGenerator.h

@@ -47,6 +47,7 @@ enum PathType
     PATHFIND_NOPATH         = 0x08,   // no valid path at all or error in generating one
     PATHFIND_NOT_USING_PATH = 0x10,   // used when we are either flying/swiming or on map w/o mmaps
     PATHFIND_SHORT          = 0x20,   // path is longer or equal to its limited path length
+    PATHFIND_FARFROMPOLY    = 0x40    // start of end positions are far from the mmap poligon
 };
 
 class TC_GAME_API PathGenerator