Xv overlay has a pretty major display corruption bug which
was bisected down to commit 3298249d8267c27235653f17379f8c
(xv: reformat source so mere mortals can understand it)
Visually I see flashing bands of alternatively greed/purple colors
that seems mixed with the normal image
The corruption the not seems to affect every frame,
It more looks like something like 1 frame over 2 are corrupted, which
visually create a flashing effect.
A (bad) screenshot on a CRT monitor is attached.
The hardware is a NV20 GeForce 2 Ti 500
Created attachment 18082 [details]
I have a very similar problem on nv20, but I bisected it to commit
9f53b2a341a81e1bff87fee8bf5c2754cac17849 "xv: remove drawable handling from hw-specific PutImage.. it's common..."
For me it affects only the real overlay. Blitter adapted works fine.
I've checked and I can confirm that:
3298249d8267c27235653f17379f8c~1 is good
3298249d8267c27235653f17379f8c has image corruption
So there might be another bug here
The blitter adapter is also unaffected here, only video overlay
After my statement on irc friday (as moondrake) I also did a bisect. Same results Mathieu Bérard. But I noticed while testing that there may be at least 2 issues, so maybe pq is also right:)
Anyway, the commit is rather big, I'll go through it tonight to see what broke.
A brief update: I spotted one error in the xv rework that darktama has now fixed. However, more issues may remain so it needs some testing (I try to look into it tonight).
After darktama's fix in commit 4b24be811b839f9f836b9f8574fc808d2182dd30, "xv: fix thinko from when source was reformatted", the overlay now works like it used to before this latest total breakage. So it was 3298249d8267c27235653f17379f8c after all.
Indeed this bug is now fixed in latest git.