[PLUG] Xlib.

[Michael Robinson]

Hello pluggers,

I need to take a demo program that displays a PNG file via Xlib and
modify the output.  It is a C program, not C# or C++.  Has xlib been
replaced by xcb?  I'm developing this for an HDMI projector hooked 
to a Raspberry Pi 3 model B.

Preferably, I don't want to pull out cairo or any other graphical
library that is heavier than Xlib.  If I have to pull out another
tool, what should I use?

I need to remove the title bar and all areas that can be clicked on, 
the image is a target for calibration.  The program that I'm trying 
to fix ASAP uses opencv, a computer vision package.  Obviously, the
program calculates or accepts user input on where the target should
project and that has to work.  So the image can't pop up willy nilly 
on the screen the way it does in the current demo program.