private void InitBoundBoxes(Vector2 position)
{
Rectangle rect = new Rectangle((int)Math.Round(position.X), (int)Math.Round(position.Y), Sprite.SpriteRect.Width, Sprite.SpriteRect.Height);
BoundBox = new RotRectangle(rect, angle);
BoundCircle = new Circle(rect.Width / 2 + rect.Height / 2); // approx size, can optimize with a get corner from rotrect
BoundBox.Origin = Sprite.Origin;
}
private Vector2[] GenerateAxes(RotRectangle r)
{
Vector2[] axes = new Vector2[4];
axes[0] = new Vector2(UR.X - UL.X, UR.Y - UL.Y);
axes[1] = new Vector2(UR.X - DR.X, UR.Y - DR.Y);
axes[2] = new Vector2(r.UL.X - r.DL.X, r.UL.Y - r.DL.Y);
axes[3] = new Vector2(r.UL.X - r.UR.X, r.UL.Y - r.UR.Y);
return(axes);
}
public bool Intersects(RotRectangle r)
{
Vector2[] axes = GenerateAxes(r);
float[] scalarA = new float[4];
float[] scalarB = new float[4];
foreach (Vector2 axis in axes)
{
scalarA[0] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(UL, axis) / axis.LengthSquared()));
scalarA[1] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(DL, axis) / axis.LengthSquared()));
scalarA[2] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(DR, axis) / axis.LengthSquared()));
scalarA[3] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(UR, axis) / axis.LengthSquared()));
scalarB[0] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(r.UL, axis) / axis.LengthSquared()));
scalarB[1] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(r.DL, axis) / axis.LengthSquared()));
scalarB[2] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(r.DR, axis) / axis.LengthSquared()));
scalarB[3] = Vector2.Dot(axis, Vector2.Multiply(axis, Vector2.Dot(r.UR, axis) / axis.LengthSquared()));
if (scalarB.Max() < scalarA.Min() || scalarA.Max() < scalarB.Min())
{
return(false);
}
}
return(true);
}