[MPlayer-dev-eng] MGA Xv sux...

[Arpi]

Hi,

> Just browsed some Xv driver's source to find out a better common vidix-like
> interface, with minimal coding requirement to convert an Xv driver to it.
> It seems it's harder than i hope, Xv drivers uses various external XF86
> structures for various purposes :(
> Anyway the design of the whole Xv thing is broken to hell.
> 
> Btw, while browsing mga's xv driver i noticed some bad thing:
> 	MGACopyMungedData()
> It does interleave planes.

I got another idea - left Xv alone _but_ extend it a little bit, using its
set/get attribute interface (similar to our control() scheme).
I also wanted to change mga Xv driver (for reference) to support direct
rendering to video memory. It is not possible ;(
There is no way to do that. The Xv driver has to provide a function to
calculate required buffer size, offsets and strides for a given widht/height
and format, but the actual memory allocation for the image buffer is handled
outside of the Xv driver (in Xv core?).
Then, the PutImage() function receives pointer to such allocated buffer to
display it.

Maybe it's just really impossible to allocate SHM memory in video ram?
Or just the boy designing it thought that every card can do DMA transfers
easily? (maybe he's right?)


A'rpi / Astral & ESP-team

--
Developer of MPlayer, the Movie Player for Linux - http://www.MPlayerHQ.hu