Cooperative Multitasking(/threading)

[dmoc]

I tried threads (and timers) but the overhead and predictability are not good for realtime 3d. A long time ago I used to program in Modula and it's cooperative multitasking(/threading) worked a dream and proved to be quite flexible when it came to fine tuning (maybe even more so than threading). I forget how in Modula several procedures were set-up to cooperate but the key statement came down to something like "yield()". It would be a nice addition to PB.