Re: Redisplay problems?

[Stefan Monnier]

>> > optimizations will not help, because you must redraw everything, and
>> > AFAIK we don't currently have a redisplay mode where the portions of
>> > matrices that were not recomputed are nevertheless redrawn.
>> They'll be redrawn from the current matrices in response to the
>> expose events.
> Only if you insist on showing incorrect contents first, and if you can
> arrange for the expose event to always be processed before the
> redisplay.

Hmm... I guess it depends on what kind of drawing operations we use.
E.g. if the redisplay optimizations include usage of "block move"
operations, then indeed, if the redisplay happens before the expose, we
may end up moving not-yet-drawn (i.e. incorrect/garbage) pixels.

Do we use things like "block move"?


        Stefan