[Pixman] [PATCH 5/8] pixman-access.c: Add floating point accessor functions

Alexander Larsson alexl at redhat.com
Tue Sep 25 05:54:38 PDT 2012

On lör, 2012-08-25 at 21:45 -0400, Søren Sandmann Pedersen wrote:
> The other direction is currently done with 4096-entry table which
> works fine for 16 bit integers, but not so great for floating
> point. So instead this patch uses a binary search in the sRGB->linear
> table. The existing 32 bit accessors for the sRGB format are also
> converted to use this method.

I implemented a custom x^2.4 and x^(1/2.4) for doubles in babl:

If you convert it to float and limit the number of chebychev terms it
might be fast enough for pixman.

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