[mcclim-devel] performance of incremental redisplay

[Andy Hefner]

On 1/2/07, Robert Strandh <strandh at labri.fr> wrote:
> I maintain my previous analysis that it would be a better idea to
> store relative positions in output records, so that moving an output
> record does not require traversing its children.

I agree completely. Use of absolute coordinates here is a particularly
boneheaded aspect of CLIM, particularly in contrast with the very nice
sheet/windowing functions based on transformations.

> The solution to this problem seems to be to realize that incremental
> redisplay must traverse all the output records anyway (to see what has
> changed), and so it would be a better idea to put off the computation
> of the bounding rectangle until the end of this entire process.

Do you think it makes sense to generally make bounding rectangles
computed lazily, caching them? Having ran into quadratic behavior a
couple times myself (during normal text output, and in the grapher),
this seemed like the logical approach.