Re: Synchronization mostly missing?

[Krzysztof Smiechowicz <deadwood-5tc4TXWwyLM@public.gmane.org>]

Luca Barbieri pisze:

> I'm not sure why this hasn't been noticed before though.
> Is everyone getting randomly misrendered OpenGL or is my machine
> somehow more prone to reusing buffers?

I reported a similar problem about 2 weeks ago. It first became apparent 
with NV40 but I also confirmed it with NV30 - in both cases it was 
visible in morph3d demo. As long as nothing changes in memory 
allocation, everything is fine. If I even move a window(which causes 
some allocations in the system) vertexes become damaged.


Some information from that previous emails:

""

I see this problem on morph3d demo. What it does is: for each frame 
create a call list and then call it 4 times.

ADDR    VRAM OFFSET
A    X
B    Y
C    X

A,B,C is the memory offset of 32kb buffer created for vertex buffer when 
call lists are compiled. X,Y is the VRAM OFFSET (bo.mem.mm_node.start)

First buffer is created (X,A). When it gets full (after around 3 frames) 
second buffer is created (Y,B). Then first one is freed. When second 
buffer is full, third is created (X,C) - here the problem start:
according to my observations, the card seems to read vertexes not from 
address C but from address A as if it somehow remembered the initial 
address binding.

Other observations:
- the data during execution of gl commands actually seems to be put into 
location C - when I switch to software path, I could track down that it 
reads data from location C - rendering is done correctly in software path
- when I comment out freeing of memory manager node (bo.mem.mm_node), so 
that the third buffer is Z,C (paired with not yet used offset of VRAM) 
then hardware rendering behaves correctly - but this will make card "run 
out" of memory as no memory manager nodes will be deallocated
- when I switch the calls of glCallList into actual rendering code and 
disable invocation of glNewList/glEndList the hardware rendering also 
behaves correctly
""

Best regards,
Krzysztof