>>>>> "KK" == Krzysztof Kosiński <[email protected]> writes:
KK> So what is the bottom line? Should we have two versions of all code, KK> one using float and one using pixman_fixed_t, or is replacing KK> pixman_fixed_t with float sufficient? The typical thing done in the audio world is to have both float and fixed versions of the algorithms and to choose one at compile time, often by way of a configure option and/or a #define. There are alternate approaches, though. Xiph provides a completely separate library for non-float decoding of vorbis. I would expect video codecs to follow that pattern, too. Pixman seems to be at a similar level. I'd suggest a look at the speex code and build for well designed example of the typical style. KK> How much slower is softfloat - a factor of 5, 15 or 500? If it is kernel-emulated floats then the factor is large enough that you want to avoid it at almost all costs for anything which occurs w/in loops. If everything which might use floats is compiled against a soft float library then things are better. But it is still worth avoiding floats in important loops. I suspect using floats would be *much* better than the existing fixeds on modern x86_64 systems. But fixed will remain important on smaller, lighter systems for some time to come. -JimC -- James Cloos <[email protected]> OpenPGP: 1024D/ED7DAEA6 _______________________________________________ Pixman mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/pixman
