Chambers <bdc### [at] yahoocom> wrote:
> Did you know that, for instance, the FPU registers
> load so fast that games used them to load bitmaps from regular memory to
> video memory?  It worked about 30% faster than a standard transfer.

  This was a very widespread urban legend back in the time when Quake
was new.
  The fact is that it's not true. You can test with pentiums of that time
that copying data from RAM to the video memory is not any faster using
the FPU (yes, I *did* test it explicitly instead of just trusting
internet rumors).

-- 
plane{-x+y,-1pigment{bozo color_map{[0rgb x][1rgb x+y]}turbulence 1}}
sphere{0,2pigment{rgbt 1}interior{media{emission 1density{spherical
density_map{[0rgb 0][.5rgb<1,.5>][1rgb 1]}turbulence.9}}}scale
<1,1,3>hollow}text{ttf"timrom""Warp".1,0translate<-1,-.1,2>}//  - Warp -

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"Warp" <war### [at] tagpovrayorg> wrote in message
news:40693a11@news.povray.org...
> Chambers <bdc### [at] yahoocom> wrote:
> > Did you know that, for instance, the FPU registers
> > load so fast that games used them to load bitmaps from regular memory to
> > video memory?  It worked about 30% faster than a standard transfer.
>
>   This was a very widespread urban legend back in the time when Quake
> was new.
>   The fact is that it's not true. You can test with pentiums of that time
> that copying data from RAM to the video memory is not any faster using
> the FPU (yes, I *did* test it explicitly instead of just trusting
> internet rumors).


Well, I never had a straight pentium to test with, but I verified myself
that it was true of the 486 line (after that I went to a K6 with MMX).

-- 
...Chambers
http://www.geocities.com/bdchambers79

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