[MPlayer-users] xvidix vo "mach64" seems broken.

[Michael Niedermayer]

Hi

On Thursday 28 February 2002 07:56, Nick Kurshev wrote:
[...]
> > > > try -vc ffdivx or -vaa_nodr
> > > > the direct rendering code doesnt work with triple buffering, ask nick
> > > > why ...
[...]
> > > And for what you've add it?
> >
> > no judder and no waiting for vsync :)
>
> Any reasonable arguments - why?
> If i's truth the I'll "borrow" your code ;)
sure, it seems that ati cards can only switch their buffers during vsync, so 
if u switch the buffer it will have no effect until vsync, where its 
automatically switched
juddering appearently did happen because, when we changed the buffer during 
page_flip() and didnt wait for vsync the buffer switch didnt happen yet and 
the old buffer was shown, but at the same time a new image was rendered into 
this buffer so the order of the frames was messed up

really displayed image number:  113322243333444446665
really displayed image:         AAAABBBBAAAABBBBBBBBA
rendered into Image:    AAAA BBBB AAAA BBBB AAAA BBBB
page flip():                F    F    F    F    F
real vsync:                v   v   v   v   v   v   v

with 2 buffers + vsync waiting after the buffer switch

really displayed image number:  111111112222222233333333444444445555
really displayed image:         AAAAAAAABBBBBBBBAAAAAAAABBBBBBBBAAAA
rendered into Image:    AAAA    BBBB    AAAA    BBBB    AAAA    BBBB
page flip():                FFFF    FFFF    FFFF    FFFF    FFFF
real vsync:                v   v   v   v   v   v   v   v   v   v

with 3 buffers:

really displayed image number:  111122223333444444445
really displayed image:         AAAABBBBCCCCAAAAAAAAB
rendered into Image:    AAAA BBBB CCCC AAAA BBBB CCCC
page flip():                F    F    F    F    F
real vsync:                v   v   v   v   v   v   v

[...]

Michael