Re: Integer pixel operations for gtk+?

[Rob Taylor <rob taylor codethink co uk>]

Koen Kooi wrote:
> Rob Taylor schreef:
>>> Koen Kooi wrote:
>>>> Daniel Amelang schreef:
>>>>>> On 2/10/07, Koen Kooi <koen dominion kabel utwente nl> wrote:
>>>>>>> -----BEGIN PGP SIGNED MESSAGE-----
>>>>>>> Hash: SHA1
>>>>>>>
>>>>>>> Michael 'Mickey' Lauer schreef:
>>>>>>>> Thanks for raising this issue Koen,
>>>>>>>>
>>>>>>>> I'd be very grateful for someone updating this patch to
>>>>>>>>
>>>>>>>> a) 2.6.10 and
>>>>>>>> b) 2.10.x
>>>>>>> Xan Lopez has expressed some interest in updating that patch (probably
>>>>>>> for 2.10.x), but
>>>>>>> won't have time till next week to do proper testing.
>>>>>>>
>>>>>>> There was some talk on the cairo list about moving image stuff into
>>>>>>> cairo and having
>>>>>>> optimized implementations there. It would be a nice experiment since
>>>>>>> the cairo developers
>>>>>>> are a lot more open to suggestions and contributions than the gtk+
>>>>>>> people.
>>>>>> Well it sure makes sense to move "image stuff" into cairo. And we're
>>>>>> always up for a challenge to optimize for a given platform, especially
>>>>>> if you can make a cairo-perf test out of it, or give us some simple
>>>>>> example code that we could turn into a perf test.
>>>>>>
>>>>>> First though, I personally would like to see some actual profiles that
>>>>>> identify this as a bottleneck. To quote Koen from the bugzilla entry:
>>>>>> "Let's hope it doesn't take another 4 and a half year to (produce a
>>>>>> profile)." Federico asked for one a long time ago.
>>>> In the span of the bug in question, a short time ago.
>>>>
>>>>>> Maybe that's why
>>>>>> the bug hasn't been recieved the needed love?
>>>> Point me to some code to do some performance test on and/or profile and I happily do that.
>>>> I asked for that before....
>>>>
>>> Koen, TBH its pretty easy to figure out a performance test for this
>>> patch; Write a test 
> 
> Ehm, and how would *I* do that? I don't code, remember? If for some reason someone feels
> like being *productive*, here's a chance.

Ah, well, that would make things difficult. Lets just say now is never a
bad time to start.. It should be relatively simple, I'm sure you have
enough experience to manage it. Feel free to ping me on IRC if you're
having problems.

>>> that loads in a test image with GdkPixbufLoader, and
>>> then scales it to several different resolutions, repeating each scale
>>> some number of times (say, 100), and exits when finished. Then just time
>>> that test, 
> 
> The scale, not loading + scale, right?

Yep.

>>> running it a number of times and calculate the average (and
>>> std deviation, for extra bonus points). Run that against vanilla and
>>> patched (and maybe also a patched version with the Cairo fast
>>> double->fixed method). Of course, it'd also be useful for testing a
>>> version that just calls out to cairo.
>>>
>>> If you can get a test up and running, I'll happily run it on N800 as
>>> well for comparison.
> 
> n800/softfloat + n800/hardfloat + n800/fixedpoint?

Well, whatever maemo is by default (EABI, softfloat?) against the fixed
point patch. I can try other things if you can hold my hand ;)

> regards,
> 
> Koen

Thanks,
Rob