Good evening,

I'm experiencing some mildly annoying behavior using the Vanishing Point drawing assistant. You see, after setting down the position of the vanishing points, guidelines are drawn from the cursor current position towards the vanishing points. That's cool, that's great! That's what all I needed. But, when I switch to the brush tool, these guidelines freeze in place and erratic lines start trailing behind my cursor. They are very dim, having about the same brightness of the vanishing point guidelines, but they accumulate. Here, I hope this image can illustrate what I mean: http://ibb.co/h6EVva

The tool itself works normally. No lag, no nothing. This is the setup I'm using (if that's of any relevance):

System settings:

OS: Debian Jessie 8.7 stable
Desktop: Dell Inspiron 15 5000 Special Edition Laptop
Tablet/monitor: Cintiq 13HD
RAM: 16 GB
Processor: Intel Core i7-5500U CPU @ 2.40Hz x 4
Graphics: Gallium 0.4 on llvmpipe (LLVM3.5, 256 bits)
Disk 1TB (966.8 GB available)

Graphics Card and Drivers:

Radeon R7 Series Graphics Card
xserver-xorg-video-ati (1:7.5.0-1)
xserver-xorg-video-radeon (1:7.5.0-1)
xserver-xorg-input-wacom

Modifications to Krita's configurations:

OpenGL disabled
Curve anti-aliasing and selection outline anti-aliasing enabled
Memory available: 15998 MiB
Memory limit: 12000 MiB (75.01%)
Internal pool: 240 MiB (2.00%)
Swap undo after: 240 MiB (2.00%)
Swap file size limit: 8 GiB

Thank you for the help. May Saint Ignucious conduct your soul to free software heaven.

hmm. That is quite odd with that tearing. My first thought it is something OpenGL related. Can you try to turn it off and see if that makes the issue go away?

It's already off, bud.

ahh sorry. Just looked at the last section of your specs. usually people don't give us that much information at the beginning. Maybe someone tomorrow can look at it. I am not too familiar with Debian and any tricks that might be needed for it to work right.

No problem. Thank you for playing!

Diogenes wrote:It's already off, bud.

The guidelines don't work unless you turn opengl on. It's because only the opengl canvas can update fast enough, while the regular qpainter canvas cannot.

You're right! I turned it on and it now behaves normally. But, you see, I have had problems with cursor lag previously, as I've shown in this post, (viewtopic.php?f=139&t=138663) and it was then recommended to me as a fix for that to turn off the OpenGL. And that solved the lag problem. So, is there any way we could make make this work as a whole?

Thank you for your help.

Ah, I am afraid the only thing you can try is either whether toggling instant preview off makes a difference or whether you can somehow update your graphics drivers...

I updated my Xorg Radeon driver to the version available in Debian's testing repository and that did the trick. Thanks!