's Multi-Threaded Dynamic Pathing System, Full Physics Support

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Yaay! I’m glad to have helped out!

That was actually the most complex part, I did a bunch of geometric tests to identify the proper points using FBox and line tests.

After obtaining the FBox that represents each poly, I then did a bunch of tests to see which one was the best for the unit to use :slight_smile:

Here’s the function I created in my custom PathFollowingComponent to initiate my geometric tests:



//Verts
bool NavPoly_GetVerts(const NavNodeRef& PolyID, TArray<FVector>& OutVerts);

//Bounds
FBox NavPoly_GetBounds(const NavNodeRef& PolyID);

//Choose Which Nav Data To Use
FORCEINLINE const ANavigationData* JoyGetNavData() const
{
	const FNavAgentProperties& AgentProperties = MovementComp->GetNavAgentPropertiesRef() ;
	const ANavigationData* NavData = GetNavDataForProps(AgentProperties) ;
	if (NavData == NULL)
	{
		NavData = GetMainNavData();
	}
	   
	return NavData;
}

//~~~
bool UJoyPathFollowCompHighest::NavPoly_GetVerts(const NavNodeRef& PolyID, TArray<FVector>& OutVerts) 
{
	//Get Nav Data
	const ANavigationData* NavData = JoyGetNavData();
	 
	const ARecastNavMesh* NavMesh = Cast<ARecastNavMesh>(NavData);
	if(!NavMesh)
	{
		return false;
	}
	
	return NavMesh->GetPolyVerts(PolyID,OutVerts);
}

//Get Box of individual poly from verts
FBox UJoyPathFollowCompHighest::NavPoly_GetBounds(const NavNodeRef& PolyID)
{
	TArray<FVector> Verts;
	NavPoly_GetVerts(PolyID,Verts);
	
	FBox Bounds(0);
	for(const FVector& Each : Verts)
	{
		Bounds+=Verts;
	}
	
	return Bounds;
}




**Geometric Analysis Using FBox**

I had to do all the geometric analysis myself! 

I recommend you check out all the convenience functions in:

**UnrealMathUtility.h**

and

**Box.h**

These are the basic tools you can use to do the analysis yourself to find the best spot!

Essential Function

I especially recommend checking out a fast trace you can do using a Line Box intersection:

UnrealMathUtility.h



/** Determines whether a line intersects a box. */
static bool **LineBoxIntersection**( const FBox& Box, const FVector& Start, const FVector& End, const FVector& Direction );

/** Determines whether a line intersects a box. overload avoids the need to do the reciprocal every time. */
static bool** LineBoxIntersection**( const FBox& Box, const FVector& Start, const FVector& End, const FVector& Direction, const FVector& OneOverDirection );

/* Swept-Box vs Box test */
static CORE_API bool **LineExtentBoxIntersection**(const FBox& inBox, const FVector& Start, const FVector& End, const FVector& Extent, FVector& HitLocation, FVector& HitNormal, float& HitTime);





**Multi-Threading**

I multi-threaded my final solution to result in best performance.

Good Luck!

I look forward to hearing about your chosen implementation!

:slight_smile: