> Fairly elaborate but you stay somewhat vague in a lot of places - in the 
> hardware section you say FPU, L1 cache, L2 cache, memory and bus speed 
> are important but not to what extend and what this means for the reader 
> - in fact the influence of memory/cache performance depends quite a lot 
> on the scene.  These parts of your guide are probably of quite limited 
> help for someone who tries to speed up his renders.

100% ACK. As you say yourself, the specific scene makes a huge 
difference with those values. I could have left it out, but IMHO the 
influence of hardware on render times should be mentioned somewhere. So 
I tried to give a basic overview of how it works (this paragraph is 
pretty much the same as the one found in the docs). Additionally, I 
wanted to make sure that the reader gets to know that the pure CPU speed 
in GHz is not the only thing that matters (as opposed to the image some 
CPU manufacturers try to create).


> What you write about performance of scanline rendering vs. raytracing is 
>   wrong in fact - like any statement that one of them is faster than the 
> other.  They just scale differently.  Also it is not that much more 
> research is going into scanline rendering algorithm improvements than 
> into raytracing techniques but of course there is a real lot of money 
> put into specialized hardware.

I'm not involved into CG research myself, so I might be wrong about how 
much is researched in which field. It's just my impression that of the 
many papers about CG you find on the net, a majority discusses 
scanline-rendering issues.
The performance comparison might be wrong in general, too, but this is 
again what applies for most people: The basic user, who renders average 
scenes, will often find that scanline rendering is faster. That's why I 
tried to make clear, that scanline may be faster, but that raytracing 
will give you more accurate results.

> Still it gives a nice outline what aspects are actually influencing the 
> render speed.
Thanks!

Florian
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