Ok, that makes sense. In essence, "RGB" and "BGR" mean different things for people talking about byte order and people talking about little endian encoding. Which makes this a difficult subject to search on.
Apparently, OpenGL supports both formats, but I have not yet found a good reference on packed pixel formats in OpenGL that is explicitly clear on this byte order issue. I am sure there must be such references, but I have not seen them recently. But I imagine that Linux and Mac running on Intel CPUs must also use little endian integer encodings. -- Raul On Thu, Mar 17, 2011 at 9:55 AM, bill lam <[email protected]> wrote: > From your link to directx page, it said blue component is stored in the > lowest byte, this is the same order as J6 glpixels/glqpixels used. > > Чтв, 17 Мар 2011, Raul Miller писал(а): >> On Wed, Mar 16, 2011 at 8:31 PM, bill lam <[email protected]> wrote: >> > Yes, flip_rgb is needed for cairo and gdi32 but not gdiplus. >> > J seems had chosen an inefficient way to represent pixsel color as an >> > integer. >> >> http://msdn.microsoft.com/en-us/library/ee719797(v=vs.85).aspx >> >> Efficient pixel formats are 32 bits wide. >> >> rgb is for directx >> http://msdn.microsoft.com/en-us/library/aa753543(v=vs.85).aspx >> >> I am not sure what bgr is for. I have a vague memory of it being used >> in .bmp files, but when I looke them up, wikipedia says they are rgb >> (wikipedia is inaccurate often enough but I still would hope that for >> something this narrow and specific someone would have noticed and >> fixed it if it was wrong) >> >> -- >> Raul > > -- > regards, > ==================================================== > GPG key 1024D/4434BAB3 2008-08-24 > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
