Fixing the mess that is XvMC?

[Kendall Bennett]

Hi Guys,

We are working on an XvMC driver for a customer of ours, and have run 
into a bit of a snag. As it stands right now it appears the work on 
libXvMC was never really completed. The current X.org 6.8.1 code base 
includes sample code for the Intel i810 (not sure if it works on the i830 
and later chipsets or not) which is split across back end driver code 
that handles surface allocation and a front end chipset specific client 
library.

The problem is that client applications that wish to use XvMC must link 
aginst both the libXvMC library *AND* one of the client specific 
libraries (libI810XvMC and libNVIDIAXvMC* etc). Having client 
applications link to hardware specific client libraries has caused major 
problems with deploying applications in binary form that work with XvMC 
out of the box. The end result is that although both MPlayer and Xine 
both support XvMC in the players, neither of them have it enabled by 
default and it is quite a chore to figure out how to enable it for your 
specific machine.

It seems to me that the best solution to this problem would be for the 
libXvMC library to make a call to the X driver to retrieve the name of 
the client side vendor library to use (just like Windows does for OpenGL 
ICD drivers). Then the libXvMC library could abstract all this away from 
the client programs and take care of this by automatically using dlopen() 
on the appropriate vendor library at runtime, without the client programs 
having to do or know anything about the chipset specific vendor 
libraries.

Since this does not exist at present, I would like to work on making this 
happen. Since I am not familiar with how to write a private interface 
between the client code and the X driver, can someone help me write the 
interface code to pass the client library name back from the X driver?

Finally I will need CVS access to get this code into the X.org 
repository, so who do I see about getting access?

Thanks!

---
Kendall Bennett
Chief Executive Officer
SciTech Software, Inc.
Phone: (530) 894 8400
http://www.scitechsoft.com

~ SciTech SNAP - The future of device driver technology! ~