David Faught wrote:
> I was expecting good things as a result of this, but was rather
> disappointed.  The before and after tally results are below.  They
> show that the B3DVector3(FloatArray) *, -, and + operation times went
> away (as expected) with pretty big increases in the primitives (this
> is just shifted from the original operations) and
> B3DVector3Array>>at:put: times, which was not expected.  What
> happened, especially with the at:put: times?

Two possibilities: First, it may be a sampling error since you are only 
using 16 msecs intervals which is extremely coarse and should not be 
used for such a quantitative comparison. Get down to 1 msec instead. 
Second, I have occasionally seen primitive tallies to be assigned to 
other than their containing methods. I'm not sure why this happens but 
the only way to find out for sure is to convert all of the primitives 
into "real sends" (e.g., put extra methods in which call the primitives).

> I could see a shift like this in the percentages, but the actual
> measured times went way up too, with the overall total time being not
> very much less for the "optimized" version.  Any ideas?

As an overall, the difference isn't too surprising. Assuming this was 
running with the same parameters, you get some six seconds overall 
speedup which is a roughly 12% speedup. That's not bad and you should 
continue along those lines (like actually measuring the "fast square 
root" since I'm not convinced that it's either correct or faster than a 
straightforward sqrt).


Cheers,
   - Andreas