From: Toni Van Remortel <t.vanremortel@ha.be>
To: ARIBAUD Albert <a.aribaud@giat-industries.fr>
Cc: Linuxppc-Embedded <linuxppc-embedded@lists.linuxppc.org>
Subject: RE: Doing floating point calculations in kernel space
Date: Fri, 17 Oct 2003 14:37:32 +0200 [thread overview]
Message-ID: <1066394252.1390.13.camel@toni> (raw)
In-Reply-To: <F886A68DA978614991E47D82EA26B54210E987@csy-exchange1.giat.intra>
> > The CPU (405GP) has no FPU, but I need to calculate sin and cos in a
> > kernel module.
>
> Hmm... Bit off-topic, but why not use tables tailored to the
> precision you need (if you want to compute any sin or cas any time)
> or the equivalent of the Bresenham algorithm (if you only want to
> draw arcs or ellipes) ?
Currently, the floating point problem is solved. I'm not going to use
default sin and cos, because they are darn too slow.
Lookuptables are way to inaccurate for the application (the formula used
can be viewed at http://www.geniaal.be/), but I'll use other faster
formula's (found a PDF from a Playstation programmer :)
Tnx for the comment.
--
Toni Van Remortel
Wetenschappelijk Medewerker - D-science lab
Real time Linux for embedded systems: http://linemb.d-sciencelab.com
Tel: +32 3 205 61 72 - Fax: +32 3 205 61 95
E-mail: t.vanremortel@ha.be
** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
next prev parent reply other threads:[~2003-10-17 12:37 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-10-17 12:16 Doing floating point calculations in kernel space ARIBAUD Albert
2003-10-17 12:37 ` Toni Van Remortel [this message]
-- strict thread matches above, loose matches on Subject: below --
2003-10-17 7:15 Toni Van Remortel
2003-10-17 7:33 ` Wolfgang Grandegger
2003-10-17 7:52 ` Toni Van Remortel
2003-10-17 8:59 ` Toni Van Remortel
2003-10-17 10:06 ` Wolfgang Grandegger
2003-10-17 12:22 ` Gary Thomas
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