How to check if a point is inside in a rectangle?

Development Programming & Scripting C++
1

I searched and found some arithmetic formula to check if a point is inside in a rectangle or polygon:
http://math.stackexchange.com/questions/190111/how-to-check-if-a-point-is-inside-a-rectangle
http://www.geeksforgeeks.org/how-to-check-if-a-given-point-lies-inside-a-polygon/

If the vertexes of rectangle are: FVector2D V1, V2, V3, V4; and the point to check is FVector2D P;
does UE4 have offered API to check it sample?

2

You need to check if your point is inside the box determined by the four vectors V1, V2, V3 et V4, here is an example from my code:



bool Utilities::IsPointInsideBox(FVector point, UBoxComponent * boxComponent)
{
	float xmin = boxComponent->GetComponentLocation().X - boxComponent->GetScaledBoxExtent().X;
	float xmax = boxComponent->GetComponentLocation().X + boxComponent->GetScaledBoxExtent().X;
	float ymin = boxComponent->GetComponentLocation().Y - boxComponent->GetScaledBoxExtent().Y;
	float ymax = boxComponent->GetComponentLocation().Y + boxComponent->GetScaledBoxExtent().Y;
	float zmin = boxComponent->GetComponentLocation().Z - boxComponent->GetScaledBoxExtent().Z;
	float zmax = boxComponent->GetComponentLocation().Z + boxComponent->GetScaledBoxExtent().Z;

	if ((point.X <= xmax && point.X >= xmin) && (point.Y <= ymax && point.Y >= ymin) && (point.Z <= zmax && point.Z >= zmin))
	{
		return true;
	}
	return false;
}

Hope it helps you.

1 Like
4

I found it:


FBox2D::IsInside(const FVector2D& TestPoint)
FBox::IsInside(const FVector& TestPoint)
FIntRect::Contains( FIntPoint P )
2 Likes
5

Many thx! Have nick day!