public AABB3D Join(AABB3D b)
{
Vector3 position = new(Math.Min(Left, b.Left), Math.Min(Bottom, b.Bottom), Math.Min(Back, b.Back));
Vector3 size = new Vector3(Math.Max(Right, b.Right), Math.Max(Top, b.Top), Math.Max(Front, b.Front)) - position;
return(new AABB3D(position, size));
}
public AABB2D Join(AABB3D b)
{
Vector2 position = new(Math.Min(Left, b.Left), Math.Min(Top, b.Top));
Vector2 size = new Vector2(Math.Max(Right, b.Right), Math.Max(Bottom, b.Bottom)) - position;
return(new AABB2D(position, size));
}
public static AABB3DIntersectionResult IntersectMovingAABBToAABB(AABB3D a, Vector3 movement, AABB3D b)
{
LineSegment3D segment = new(a.Center, a.Center + movement);
AABB3D other = b.Inflate(a.Size);
return(IntersectLineSegmentToAABB(segment, other));
}
public bool Intersects(AABB3D b)
{
return(Right > b.Left &&
Left < b.Right &&
Front > b.Back &&
Back < b.Front &&
Top > b.Bottom &&
Bottom < b.Top);
}
public AABB3DIntersectionResult(Vector3 position, Vector3 movement, AABBFace face, AABB3D other)
{
Position = position;
Movement = movement;
Face = face;
Other = other;
Normal = Face switch
{
AABBFace.Left => - Vector3.UnitX,
AABBFace.Right => Vector3.UnitX,
AABBFace.Bottom => - Vector3.UnitY,
AABBFace.Top => Vector3.UnitY,
AABBFace.Back => - Vector3.UnitZ,
AABBFace.Front => Vector3.UnitZ,
_ => Vector3.One.Normalized()
};
}
}
public static AABB3DIntersectionResult IntersectLineSegmentToAABB(LineSegment3D line, AABB3D box)
{
float tMax = 1;
float tMin = 0;
Vector3 direction = line.Movement;
for (int i = 0; i < 3; i++)
{
if (Math.Abs(direction[i]) < float.Epsilon)
{
if (line.Start[i] <= box.Min[i] || line.Start[i] >= box.Max[i])
{
return(default);