Re: [pygame] ARGB vs. RGBA

[Jakub Piotr CÅapa <jpc@xxxxxxxxxxxxx>]

Tim Ansell wrote:
> Hello,
>
> You can use my SDL_Surface.py hack to get a ctypes pointer to the pixel
> data. http://www.thousandparsec.net/repos/libmng-py/mng/pygame/
>
> I needed this to make libmng-py as fast as possible.

Thanks but I'm unsure if this helps. I've got a Python buffer which is 
already allocated by cairo and I want pygame to use it as an image I can 
blit to screen later. This method is in the cookbook and should be fast 
(no memory copying for cairo->pygame conversion).

It just that I don't understand why ARGB isn't just ARGB in memory (1 
byte A, 1 byte R, 1 byte G and 1 byte B). Look at lines 627 and 629 in 
src/image.c:
#v+
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
                                        0xFF<<24, 0xFF, 0xFF<<8, 0xFF<<16);
#else
                                        0xFF, 0xFF<<24, 0xFF<<16, 0xFF<<8);
#endif
#v-
The BIG_ENDIAN part should be 0xFF<<16, 0xFF<<8, 0xFF, 0xFF<<24; the 
same as LIL just in reverse order.


--
regards,
Jakub Piotr CÅapa