[ODE] Sweep-and-Prune space for ODE
nearaz at interamotion.com
Thu Nov 25 21:14:02 MST 2004
> It would be useful in removing the float/double problem anyway.
It wasn't the problem for me (I used ODE in double precision, and SAP space
uses single precision internally). Yes, there are quite many casts involved,
but oh well :)
> It'd be interesting to see how the performance goes between the different
> sorts in a complex test.
Sure. Of course, this doesn't change the SAP space much - you just sort box
intervals with another sorter, and that's it.
Another interesting thing would be implementing "classic" SAP that
incrementally re-sorts moved AABBs instead of doing full sort each time.
Shoulf be faster if geoms are moving slowly, but can be very slow if there's
complete chaos happening with your geoms (Pierre has some measurements on his
Alas, I never got time to implement that, especially considering that now
we're doing network management software and not interactive entertainment
> in contrived box stacks, lots of identical values aren't ideal for
> some sorts, while radix doesn't care.
Yes, especially for things like quicksort. On the other hand, most "standard"
sort implementations (eg. STL; don't know about qsort()) have special code
paths for nearly-sorted data.
Aras Pranckevicius aka NeARAZ
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