what part of X maps screen coordinates to objects?

[Alan Coopersmith]

On 05/11/15 12:22 PM, George Nychis wrote:
> I am trying to gain a very technical understanding of how X maps coordinates on
> the 2d screen to objects.  For example, there are many applications running with
> graphical interfaces to them active on the screen, and each application
> interface has dozens (if not hundreds) of objects.  Some objects are contained
> within other objects.
>
> So, what I am trying to learn more about is how X maps a screen coordinate (and
> an action like a mouse click) to an object quickly.  In particular, when there
> are objects within objects, how it narrows the search down to the "smallest"
> element that your mouse is hovering over when a click event fired.
>
> I'd love to know about what data structures and algorithms are used to perform
> this mapping between the 2D graphical space to objects.  Pointers to prior
> discussion, documentation, code... anything is helpful.

X only maps to the window - it's up to the application to map to objects in that
window.

-- 
	-Alan Coopersmith-              alan.coopersmith at oracle.com
	 Oracle Solaris Engineering - http://blogs.oracle.com/alanc