[cairo] Fixed point bug

[Krzysztof Kosiński]

W dniu 13 grudnia 2010 20:47 użytkownik M Joonas Pihlaja
<jpihlaja at cc.helsinki.fi> napisał:
>
> Hi Krzysztof,
>
> On Sun, 12 Dec 2010, Krzysztof Kosiński wrote:
>
>> I recently submitted a bug that, once fixed, would allow Inkscape to
>> use Cairo for all drawing.
>
> Sorry, I haven't been following your work very closely.  Could you
> remind me about what exact guarantees you require from cairo/pixman
> with respect to coordinate ranges and precision and accuracy?

I think this would avoid most problems:

- Gradient coordinates should have at least 24 bits of precision in
the integral part, or be expressed in a floating point format.
- Transformation matrix elements should have 32-bit floating point
precision on platforms with an FPU.
- The test case in the bug should work at least up to 1000000, and
preferably up to INT_MAX.

Regards, Krzysztof