public BBox Intersection(BBox other)
{
var x0 = Math.Max(Left, other.Left);
var y0 = Math.Max(Bottom, other.Bottom);
var x1 = Math.Min(Right, other.Right);
var y1 = Math.Min(Top, other.Top);
if (x0 <= x1 && y0 <= y1)
{
return(new BBox(x0, y0, x1, y1));
}
else
{
return(null);
}
}
// BUGGO: Yikes this suddenly broke dramatically when I re-ordered the
// constructor arguments for BBox's. I thought I fixed all the instances
// where that mattered though!
public override Intersection IntersectBBox(BBox other)
{
var intersectionBBox = bbox.Intersection(other);
if (intersectionBBox == null)
{
return(null);
}
var contact = intersectionBBox.Center();
// XXX: rather kludgy and approximate; should take into account starting velocity, etc.
var dx0 = contact.X - other.Left;
var dx1 = other.Right - contact.X;
var dx = Math.Min(dx0, dx1);
var xside = dx0 < dx1 ? -Vector2d.UnitX : Vector2d.UnitX;
var dy0 = contact.Y - other.Bottom;
var dy1 = other.Top - contact.Y;
var dy = Math.Min(dy0, dy1);
var yside = dy0 < dy1 ? Vector2d.UnitY : -Vector2d.UnitY;
var ds = Math.Min(dx, dy);
var sideNormal = dx < dy ? xside : yside;
var flat = dx < dy ? intersectionBBox.Dy : intersectionBBox.Dx;
return(new Intersection(contact, sideNormal, 0.5 * ds, -0.5 * ds, flat, -flat));
}
public bool IntersectsBBox(BBox other)
{
return(((Left <= other.Left && other.Left <= Right) || (other.Left <= Left && Left <= other.Right)) &&
((Bottom <= other.Bottom && other.Bottom <= Top) || (other.Bottom <= Bottom && Bottom <= other.Top)));
}
public override void Translate(Vector2d delta)
{
this.bbox = bbox.Translated(delta);
}
public BoxGeom(BBox bbox)
{
this.bbox = bbox;
}
public BoxGeom(double x0, double y0, double x1, double y1)
{
bbox = new BBox(x0, y0, x1, y1);
}
public override Intersection IntersectBBox(BBox other)
{
return(null);
}
public abstract Intersection IntersectBBox(BBox other);
