[cairo] Fwd: Qt Vs Cairo performance comparison

[Kalle Vahlman]

(I again didn't check the size of the logs I was about to send
attached, sorry for the spam Carl)

[Dropping performance-list, as this is cairo-development only]

2006/10/25, Carl Worth <cworth at cworth.org>:
> Speed up _cairo_fixed_from_double
> https://bugzilla.mozilla.org/show_bug.cgi?id=311980
>
>   This is an important one, and one which will be particularly
>   interesting to the people using embedded systems that are allergic
>   to floating-point. My comment in the bug still stands:
>
>         before I commit this to cairo proper, I'd like to see this
>         version made conditional on a configure-time check so we have
>         better assurance that it will actually work on a wide range of
>         platforms.
>
>   I still haven't seen a patch with that check submitted, and I'd like
>   to have it.

While Ross and friends search for their patches ;) would the attached
patch look acceptable? (I'll put it in the bug if it is...)

I wasn't sure if cairo-features.h would be better for this or not, but
I opted to use config.h since it's really a platform-specific option
(or rather, option not available for every platform), not a feature.

Logs of perf runs:
http://iki.fi/zuh/without-fast-conversion.log
http://iki.fi/zuh/with-fast-conversion.log

>   Oh, and I used to fear that run-time checks for features at
>   configure-time would be problematic, but I've recently found that
>   scratchbox magically supports these for embedded development. So I
>   don't have a problem relying on these and telling users to either
>   1. Compile natively. 2. Cross-compile with scratchbox. or 3. Compile
>   either way and hand-write the config.h settings as appropriate.

Black magic is good magic ;)

--
Kalle Vahlman, zuh at iki.fi
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-- 
Kalle Vahlman, zuh at iki.fi
Powered by http://movial.fi
Interesting stuff at http://syslog.movial.fi
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