fix(collision handling movement) allow to deativate the collision detection in...

fix(collision handling movement) allow to deativate the collision detection in case users manage to get stuck in something. In this case virtual steering is disabled but also physical collision checks so users can move out of the collision

Source/RWTHVRToolkit/Private/Pawn/Navigation/CollisionHandlingMovement.cpp

@@ -67,7 +67,14 @@ void UCollisionHandlingMovement::TickComponent(float DeltaTime, enum ELevelTick
 			}
 		}
 
-
+		// in case we are in a collision and collision checks are temporarily deactivated, we only allow physical
+		// movement without any checks, otherwise check collision during physical movement
+		if (bCollisionChecksTemporarilyDeactivated)
+		{
+			ConsumeInputVector();
+		}
+		else
+		{
 			// so we add stepping-up (for both walk and fly)
 			// and gravity for walking only
 			MoveByGravityOrStepUp(DeltaTime);
@@ -75,6 +82,7 @@ void UCollisionHandlingMovement::TickComponent(float DeltaTime, enum ELevelTick
 			// if we physically (in the tracking space) walked into something, move the world away (by moving the pawn)
 			CheckForPhysWalkingCollision();
 		}
+	}
 
 	if (NavigationMode == EVRNavigationModes::NAV_NONE)
 	{
@@ -150,6 +158,7 @@ void UCollisionHandlingMovement::CheckAndRevertCollisionSinceLastTick()
 		if (!CreateCapsuleTrace(CapsuleLocation, CapsuleLocation).bBlockingHit)
 		{
 			LastCollisionFreeCapsulePosition = CapsuleLocation;
+			bCollisionChecksTemporarilyDeactivated = false;
 		}
 		return;
 	}
@@ -157,8 +166,17 @@ void UCollisionHandlingMovement::CheckAndRevertCollisionSinceLastTick()
 	// check whether we are in a collision at the current position
 	if (CreateCapsuleTrace(CapsuleLocation, CapsuleLocation).bBlockingHit)
 	{
-		// if so move back to last position
-		UpdatedComponent->AddWorldOffset(LastCollisionFreeCapsulePosition.GetValue() - CapsuleLocation);
+		// if so move back to last position, but only if that position is still collision free
+		// since the user might have moveed physically in between
+		FVector LastCapsulePos = LastCollisionFreeCapsulePosition.GetValue();
+		if (!CreateCapsuleTrace(LastCapsulePos, LastCapsulePos).bBlockingHit)
+		{
+			UpdatedComponent->AddWorldOffset(LastCapsulePos - CapsuleLocation);
+		}
+		else
+		{
+			bCollisionChecksTemporarilyDeactivated = true;
+		}
 	}
 	else
 	{
@@ -175,6 +193,13 @@ void UCollisionHandlingMovement::MoveOutOfNewDynamicCollisions()
 		FVector ResolveDirection = 1.5f * ResolveDirectionOptional.GetValue(); // scale it up for security distance
 		UpdatedComponent->AddWorldOffset(ResolveDirection);
 
+		// check whether this helped in resolving the collision, and if not deactivate collision checks temporarily
+		if (CreateCapsuleTrace(UpdatedComponent->GetComponentLocation(), UpdatedComponent->GetComponentLocation())
+				.bBlockingHit)
+		{
+			bCollisionChecksTemporarilyDeactivated = true;
+		}
+
 		// invalidate the last collision-free position, since apparently something changed so we got into this collision
 		LastCollisionFreeCapsulePosition.Reset();
 	}
@@ -195,8 +220,8 @@ void UCollisionHandlingMovement::CheckForPhysWalkingCollision()
 	if (HitResult.bBlockingHit)
 	{
 		const FVector MoveOutVector = HitResult.Location - CapsuleLocation;
-		// move it out twice as far, to avoid getting stuck situations
-		UpdatedComponent->AddWorldOffset(2 * MoveOutVector);
+		// move it out a bit farther, to avoid getting stuck situations
+		UpdatedComponent->AddWorldOffset(1.2f * MoveOutVector);
 	}
 }
 

Source/RWTHVRToolkit/Public/Pawn/Navigation/CollisionHandlingMovement.h

@@ -85,4 +85,8 @@ private:
 	// just stored for performance gains;
 	UPROPERTY(VisibleAnywhere, Transient, DuplicateTransient)
 	TArray<AActor*> ActorsToIgnore;
+
+	// if a collision happens and cannot be resolved (e.g. the user crouched, walked under something and stood up)
+	// we remporarily deactivate all checks until the user is in a collision free situation again
+	bool bCollisionChecksTemporarilyDeactivated = false;
 };