function BoundingBox(minx = noone, miny = noone, maxx = noone, maxy = noone) constructor {
	self.minx = minx;
	self.miny = miny;
	self.maxx = maxx;
	self.maxy = maxy;
	
	self.width  = maxx - minx;
	self.height = maxy - miny;
	
	static addPoint = function(px, py) {
		minx = minx == noone? px : min(minx, px);
		miny = miny == noone? py : min(miny, py);
		maxx = maxx == noone? px : max(maxx, px);
		maxy = maxy == noone? py : max(maxy, py);
		
		width  = maxx - minx;
		height = maxy - miny;
	}
	
	static lerpTo = function(bbox, rat) {
		var b = new BoundingBox(
			lerp( minx, bbox.minx, rat ), 
			lerp( miny, bbox.miny, rat ), 
			lerp( maxx, bbox.maxx, rat ), 
			lerp( maxy, bbox.maxy, rat )
		);		
		return b;
	}
	
	static clone = function() { return new BoundingBox(minx, miny, maxx, maxy); }
}

function BBOX() { return new __BBOX(); }
function __BBOX() constructor {
	x0 = 0; x1 = 0; 
	y0 = 0; y1 = 0; 
	
	xc = 0; yc = 0;
	w  = 0; h  = 0;
	
	static fromPoints = function(x0, y0, x1, y1) {
		self.x0 = x0; 
		self.x1 = x1; 
		self.y0 = y0; 
		self.y1 = y1; 
	
		xc = (x0 + x1) / 2; 
		yc = (y0 + y1) / 2;
		w  = x1 - x0; 
		h  = y1 - y0;
		
		return self;
	}
	
	static fromWH = function(x0, y0, w, h) {
		self.x0 = x0; 
		self.x1 = x0 + w; 
		self.y0 = y0; 
		self.y1 = y0 + h; 
	
		self.xc = (x0 + x1) / 2; 
		self.yc = (y0 + y1) / 2;
		self.w  = w; 
		self.h  = h;
		
		return self;
	}
	
	static clone = function() { return BBOX().fromPoints(x0, y0, x1, y1); };
}