nanogui@linuxhacker.org

Hi

I have been experimenting with Microwindows on a custom MPC823 board
running Hard Hat Linux 2.2.14 and so far I am impressed with the rich
features
and small size of the package.

I am however disappointed with the speed of the graphics operations and I
think (hope) there must be some unnecessary bottleneck somewhere.
When I run the demos, for example mdemo with the rotating pie chart, the
rotating pie visibly flickers and if I close a window, causing the "under
construction"
background to be redrawn, that takes about 1-2 seconds to redraw.  Also
the vncviewer is painfully slow, takes about 10 seconds to redraw a full
screen.

Our board runs at 50 MHz and has 16MB of SDRAM.  The display is a 640x480
pixel color TFT, setup for 8 bits per pixel.  The display is set up
similarly as the
RPXLITE lcd driver, as a frame buffer device.

I know Microwindows has been used on other MPC823 designs, like Embedded
Planetīs RPXLITE (LinuxPlanet).  Can anyone comment on the graphics
drawing speed in Microwindows on the LinuxPlanet ?

I think there must be something wrong, either with my port of Linux to our
board,
or there must be some bottleneck in the pixel drawing routines of
Microwindows.
I say this because we have run another window system with another OS on the
same board and although that window system is very primitive (no clipping
etc.)
it was drawing much much faster.

Can anyone provide input ?


Jon Benediktsson
Marel hf.