Best practice regarding different (0,0) origins

I have a graphics lib, where the origin (0,0) is at the top/left, and rects use a top/left and width/height notation.

rbang origin (0,0) is bottom/left and uses a bottom/left, top/right notation.

So, when inserting rects from the graphics lib, I use code like this to update the same rectangle:

• r = rectangle
• xll = x lower-left
• yll = y lower-left
• xur = x upper-right
• your = y upper-right

rbang.Replace(
	[2]float64{
		float64(r.xll),
		float64(r.yll)},
	[2]float64{
		float64(r.xur),
		float64(r.yur)},
	r,
	[2]float64{
		float64(r.GetLeft()),
		float64(r.GetTop())},
	[2]float64{
		float64(r.GetLeft() + r.GetWidth()),
		float64(r.GetTop() + r.GetHeight())}, r)

The problem is, that I have a very simple three rects layout (root, two childs with 50% width and 100% height of root), where a search with a point inside c2, returns the root node and c1... and not the root node and c2.

Reproduce the three-rectangle layout described in the issue, using the shown Replace coordinates and a point inside c2. Then inspect the point-search and rectangle-replacement entry points to determine how the coordinate origins are interpreted. Done means the search returns the root and c2, rather than the root and c1.