OPENSTEP 4.2 vmware SVGA

[Frederic Stark]

Hi,

Boring weekend. I took my OS42 CDs, vmware, the diff to the vmware 
module of XFree86, the drivers example from OS42, a dozen of cup of 
coffee and started to hack an OPENSTEP42 vmware SVGA driver.

I am to the point where I get it running in 1024x768/24bits (yep, the 
values are hard-coded for now). Code is _very_ ugly, as this is my first 
OS42 driver (OS42 have no documentation on the DriverKit, and I can't 
get my hands back on my 3.3 CDs). I can probably get something more 
usable next week-end. I can release what I have for the impatient, of 
course.

The problem is that the DPS server never tell my driver when screen have 
been written to, so vmware don't know when to update the real screen 
(ie: there are 'phantoms' left in a lot of places). I don't think the 
NeXT window server was ready to work with a 'buffered' device.

Any idea about how I can solve that ? I can think about several solutions:

1/ Don't care (by moving the vmware window, the 'phantoms' disapear 
because vmware flushes the screen)

2/ Implement a /dev device and a user-land utility to tell the driver to 
flush the screen (every one second, for instance).

3/ Get a PostSript master to try to hack WindowPackage.ps to know if the 
server did something. Alternatively, I could try to patch the 
WindowServer binary.

4/ Play with mach memory to know if window server wrote to the 
framebuffer. Issue a flush to vmware 1/10th of a second later. It must 
be possible, but I have the slighest clue about how to do it.

Any other trick ?

Cheers,

--fred