[Goodie] RE: Squeak on framebuffer?
Andreas Raab
Andreas.Raab at gmx.de
Tue Mar 26 20:17:46 UTC 2002
> There are important details
> however, like handling the pixel endianness & RGB layout
> right. With extra trickery one can also save memory by making
> the screen buffer memory actually be part of the Display form
> bitmap - like I do on the Acorn port.
Well, actually the itsy days are long gone - these days all you need is
a little bit of support through the surface manager in order to make
your own FB display. Just for the heck of it, I've written a little FB
driver plugin which is attached. Note that these days we don't even have
to worry about endianess and colors - this has been fixed over time and
BitBlt is quite capable of handling almost everything correctly[*] (the
test case uses a 16bpp little endian display with red and green bits
swapped ;-)
[*] Under the assumption that pixel words go left-right and top-down
which is apparently _not_ true on all hardware (like PDAs).
The ST side is pretty trivial and the C part self-explanatory (I hope).
If anyone is really interested in this stuff let me know.
Cheers,
- Andreas
-------------- next part --------------
A non-text attachment was scrubbed...
Name: FBTest.st
Type: application/octet-stream
Size: 5354 bytes
Desc: not available
Url : http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20020326/d80f5679/FBTest.obj
-------------- next part --------------
A non-text attachment was scrubbed...
Name: simplefb.c
Type: application/octet-stream
Size: 4917 bytes
Desc: not available
Url : http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20020326/d80f5679/simplefb.obj
More information about the Squeak-dev
mailing list
|