[sugar] Emulating the laptop display with Xephyr

[Manu Cornet]

Hi all !

[Reposting from devel at laptop.org, on Marco's request :-) ]

I already made a small report about this in my "weekly summary" for
Summer of Code projects, but I've been told that it would be a good
idea to advertise it a little more properly on the list, so here it is
:)

It seems necessary to emulate the laptop's display and the DCON chip's
special features (color swizzling, antialiasing) while designing
Sugar, in order to keep an eye on what things will actually look like,
and address problems such as small graphic elements (small fonts, thin
lines).

Here :

http://www.manucornet.net/pub/olpc/xephyr_swizzle.diff

you will find a patch for Xephyr (in particular, the
hw/kdrive/ephyr/hostx.c file) that emulates the laptop's display, with
both color swizzling and antialiasing.

There are a few screenshots on the project's wiki page :

http://wiki.laptop.org/go/GTK_for_OLPC

In particular, check out the difference between antialiased and not
antialiased swizzling :

http://wiki.laptop.org/go/GTK_for_OLPC#Color_swizzling_and_antialiasing

If you're designing anything from the Sugar UI, you might want to give
it a try.

This display simulation is not actually loyal to the final appearance,
since the display will have much more luminosity than this (as far as
I know), but it's already a good preview. Plans are also to make the
display 16 bit (instead of 24 bit currently) to match the actual
hardware more closely.

Of course, feedback is most welcome, especially bug reports and
screenshots!

Cheers,
Manu