Re: [grt-talk] SDL Rendering window

[Jason Dagit]

Nikodemus Siivola wrote (on Mon, 7 Apr 2003 at 16:16 +0300):

 > Some ideas:
 > 
 > What if we updated the screen per time, not per row: check how long
 > it has been since last update, and if necessary blit anew. This way
 > renders that slow down to crawl in the middle of a row get blitted
 > even in the middle, and renders that go fast can be blitted several
 > rows at a time.  Refresh rate could be user configurable.

I like this idea too.  Sdl has timer events that you can receive I
think, but I don't know if we can interrupt and resume execution if we
use them...

 > Would it be possible to open a new window for each rendered image?
 > I realize we would either have to spawn threads, which on CMUCL is
 > x86 specific, or do some pretty funky event-looping.

I'm not sure how to do this.  1) Looking at the api for sdl there is
no obvious way to create a second window.  2) cl-sdl does not support
threads.

Do you think we could use uffi to interface with posix threads?  Then
we would be ``portable'' in some sense and still have threads.  It's a
bummer that so many of the cool things are not portable.

 > Hmm. Does cl-sdl provide the SDL-threads? Maybe we could use them:
 > after rendering has finished start a new event-handler loop in an
 > sdl-thread, that just waits for close-event. Dunno if it's doable,
 > though.

Perhaps, but the way is not clear and we would need to extend the
current cl-sdl to get there.

If you have any ideas on how let me know, I think these would be good
changes.

Jason