transparent cairo rendering

[Jose Hevia <jose francisco hevia gmail com>]

Hi, I have been fighting for a long time with a very simple program I
can't make work the way it should.

The question is:

Is that a bug or is it my fault?

Here you see the program when minimized:
http://wittiza.com/grapes1.png

Here when screen size changes:
http://wittiza.com/grapes2.png
The old paint in the corner doesn't let the correct rendering to happen.

Here you have the simple code:
http://wittiza.com/grapes.c
http://wittiza.com/grapes.h

Here the scrip for building
http://wittiza.com/gen_grapes

All that counts is in the expose function, seems when I told him to
destroy the surface and create it again he doesn't destroy it. I don't
know why.

This very simple thing makes much complex programs difficult to do in cairo.

Bye