On Sun, Aug 12, 2007 at 10:22:38AM -0400, Joubert Nel wrote:
Hi Joubert,
I'm keen on using CL-Cairo2 as a means to draw GUIs. I've done some initial exploration of the library and am wondering:
- There's an xlib-context example, but the windows are fixed-size. Is
it possible to make resizable windows?
The main problem with X is refreshing the window when X asks for it (ie the window receives an Expose event). In order to do it correctly, you either have to keep track of all operations or double-buffer. cl-cairo2 does the latter, as it is easier to implement, but this does not allow resizing.
Peter Hildebrandt experimented with the former approach:
http://groups.google.com/group/comp.lang.lisp/msg/9258d245145323b3
you might want to ask him about the current status. This approach would allow resizing, but is more complicated. If you know what subset of cl-cairo2 you will be using, perhaps you can get away implementing recording operations for that subset.
- Is it possible to receive mouse and keyboard events int the
xlib-context?
The framework is there, you just have to write and event handler.
A new version of cl-cairo2 will be released tomorrow, which contains a rewritten x11 surface, implemented entirely in Lisp using CFFI (no extra C glue). If you want to refine the event handler, I suggest you wait for that and your job will be much easier.
Best,
Tamas