Re: [LAD] "enhanced event port" LV2 extension proposal

On Fri, 2007-11-30 at 09:45 +0000, Krzysztof Foltman wrote:
> Dave Robillard wrote:
>
> > We could use float I guess to save a bit of space, but I definitely
> > prefer floating point. Fixed point is just a PITA, modern CPUs are much
> > faster at FP anyway, why bother?
>
> 1. The "modern CPUs are much faster at FP" thing is a myth that shows up
> here and there and is usually taken as a gospel by people who don't know
> what they're doing (or what their CPU is doing).

The "Fixed point is faster than FP" thing is a myth that shows up here
and there and is usually taken as gospel by people who don't know what
they're doing (or what their CPU is doing) ;)

Fixed point is a PITA. Time based effects and whatnot do math on time
stamps, and doing math on fixed point is a massive nuisance compared to
floating. With floating, if you want to time stretch by a factor of
2.... multiply by 2. Fixed? Well, first write your fixed point
arithmetic library, then.........

Unless there's very /significant/ advantages to bothering with it,
well.. why bother with it. I've advocated high precision floating point
in the past because 'groove' effects and such are obviously much better
off with such a representation.

At the end of the day, for basic synths etc. timestamp things aren't
going to be a remotely significant part of the CPU time spent by a
plugin; I doubt the fixed point nuisance is worth it.

Premature optimisation is the root of all evil...
 
-DR-

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Received on Sun Dec 2 00:15:02 2007