Problem with custom drawing and expose events

["Ole Laursen" <olau iola dk>]

Hi!

I'm trying to make SDL draw in a widget. I started from the gtksdl
code on Sourceforge which derives from GtkWidget, and things are so
far working fine except for some corner issues with expose events.

When double buffering is enabled for the widget, I get the right
expose events as far as I can tell. The expose handler asks SDL to
redraw its surface to the screen, which appears to work fine but then
immediately afterwards the window is overwritten with the background
colour of the widget? Any suggestions?

The funny thing is that if I add a delayed callback which after 1 ms
requests SDL to redraw yet again, things appear to be working more or
less.

I have put a small example here with the code (together with a tarball):

http://people.iola.dk/olau/gtksdl/


I have also tried disabling double buffering. Then the expose events
appear to be much more imprecise but at least the window is not
cleared with the background colour. On the other hand I don't get any
expose events at all when moving another window on top of the window.
And I badly need those.

(Please keep the CC as I'm not on the list.)

--
Ole Laursen
http://www.iola.dk/