Re: [pygame] [BUG] SRCALPHA - unexpected behaviour.

["René Dudfield" <renesd@xxxxxxxxx>]

This page shows how to use keyword arguments:
http://72.14.253.104/search?q=cache:t00uWSg_17QJ:fraca7.free.fr/blog/index.php%3F2006/12/30/55-python-c-api-part-iii+python+keyword+arguments+C+api&hl=en&ct=clnk&cd=3

Cheers,

On 8/22/07, René Dudfield <renesd@xxxxxxxxx> wrote:
> Hello,
>
> sorry... I meant that you need to RAISE, then return -1;
>
> yeah, I think the keyword arguments do cause bugs...  However it does
> say in a few places that they aren't used like keyword arguments.
> Definitely one of pygames warts.
>
> That'd be great if you could test out keyword argument performance.
> The docs are here: http://docs.python.org/api/arg-parsing.html  Look
> down the page at ... ParseTupleAndKeywords .  Then if you can't figure
> out usage from that page(no examples are there) check the python
> source, or google for ParseTupleAndKeywords.
>
> The SRCALPHA bug has caused a lot of confusion too... hopefully that
> won't happen now so much.  I usually just used convert_alpha() as a
> work around for not understanding how to get SRCALPHA working too.
>
>
> On 8/22/07, Brian Fisher <brian@xxxxxxxxxxxxxxxxxxx> wrote:
> > On 8/21/07, René Dudfield <renesd@xxxxxxxxx> wrote:
> > > It turns out you need to raise exceptions from init methods like this:
> > >         RAISE (PyExc_SDLError, SDL_GetError ());
> > >         return -1;
> > >
> > I'm not sure what part of those to lines you are referring to when you
> > say "like this" - It looks like you are saying all init methods must
> > raise an exception type of SDL error and must propagate the text of an
> > SDL error - but if your error doesn't come from SDL, than I can't see
> > how that would apply?
> >
> >
> > > Another TODO is to check for endian compliance... I'm not sure if the
> > > masks are set correctly in there for big endian.  There's no checks in
> > > the source for endian anyway.
> > >
> > I don't see why endian-ness would have anything to do with the masks
> > you pass in... if you passed in some masks, than I would assume those
> > are the mask you want to use... like say you passed in a mask that
> > says blue is in the msb - then you want it in the msb, right?
> > endianness only affects the translation from byte order to byte
> > significance in an int... i.e. it would only be an issue if they had
> > been asking for byte order and we were building a mask from that.
> >
> >
> > > However I haven't added your test for keyword arguments yet.  I'm not
> > > sure it's a good idea or not to add keyword argument support to all
> > > the functions this late in the release process.  We'd need a bunch
> > > more tests, and need to measure any performance difference adding
> > > keyword arguments would make.  If keywords don't add any performance
> > > change for the case when they are not used, then they should
> > > definitely go in.  If it makes games drop from say 30fps to 20fps...
> > > then they  should definitely not go in.  We need to test it.
> > >
> > Well I'd be happy to do a lot of the coding and performance testing
> > for supporting keyword arguments if I knew how to write extension code
> > to make keyword arguments work... does anybody know how to do that?
> >
> > Also, for what it's worth, after I discovered this bug, I found that
> > it affected half of the times I had made surfaces, and in some places
> > I put in convert_alpha crap to work around it. meaning I think people
> > hit the keyword argument not working thing a lot, especially
> > considering the docs imply the keyword arguments will work.
> >
>