[cairo] Cairo, XRender, OpenGL, Glitz, confusion

[Bill Spitzak]

Pressebüro Martin Möller wrote:
> Hi all,
> 
> I'm trying to understand how all these elements: cairo, glitz, xrender,
> opengl work together or depend on each other:
> 
>>From a little reading, I understand it like this:
> 
> Cairo is based on Glitz which is based on OpenGL which uses Xrender for
> talking to the graphics hardware.
> 
> I this correct? I need a little clarification! :-D 
> Thanks!

I think it is more like this:

Cairo ---> Glitz ---> OpenGL ---> Hardware
       \                        /
        \-----> Xrender--------/

Ie Cairo can either use OpenGL or Xrender to draw on the hardware. This 
is decided by the type of cairo_surface that is created.

The fact that Glitz is in the diagram is kind of arbitrary. Some 
functions that are called are in a library called Glitz. Trying to draw 
diagrams like this though you can always add more things to each arrow. 
You could break it down into individual procedure calls, in which case 
this line could be very long with many words in it.