Re: Quite remarkable! (Lua as a waveform visualisator)

[Asko Kauppi <asko.kauppi@...>]

My intention wasn't to make direct Lua/C speed comparisons.  It was to 
show that Lua can be used in places where -at least I- thought it 
couldn't.  The point is, that the whole application side was made with 
Lua.  The next phase would be making colorful FFT-displays (those 
bouncing bars) also in pure Lua.  I'll leave that as an exercise. :)

-ak

For those interested, the Lua code is attached.
The original is here: 
http://jcatki.no-ip.org/SDL_mixer/SDL_mixer_demos.zip


4.4.2005 kello 16:18, Adam D. Moss kirjoitti:

 Asko Kauppi wrote:
> > I eventually did it only the "userdata int array" way, as suggested 
> > on  the list, and the results are quite remarkable:
> > Lua:
> >     fps=13.70
> > Native C:
> >     fps=43.22
> > The application is an SDL mixer demo that plays a tune and  
> > simultaneously shows its waveform on the screen.  The 43->13 fps 
> > change  is hardly noticable to the eye, certainly much less than I 
> > expected  (the C code is tight, and the mixed sound data is passed as 
> > 2048 bytes  per callback).  Well done, Lua!!  :)
>
> Without knowing how much time is spent in the non-waveform-generating
> code it's impossible to say how well Lua is doing here.  I mean, sure,
> Lua is a pretty good performer, but this test doesn't really say much
> either way (it most definitely doesn't begin to imply, for example,
> that the Lua code is about 1/4 as fast as its equivilent C code). :)
>
> --Adam
> --
> Adam D. Moss   -   adam@gimp.org

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