Panning causes visual tearing

[Andrew Benson]

I run Inkscape 0.48.4.1 32-bit for Windows 7 Ultimate Version 6.1 (Build 7600). This problem also occurs on Inkscape 0.48.4.1 64-bit.

Whenever I pan the view, the drawing tears momentarily, leaving behind a temporary afterimage of the edges of the current view.
This occurs using both horizontal and vertical mousewheel panning, as well as click-dragging while holding down the mouse wheel button. The issue occurs even with extremely small files (such as a single line on a blank background).

Attached is a picture demonstrating what the issue looks like.

Last note: this occurs with every inkscape file I use.

[jazzynico (jazzynico)]

Not reproduced on Windows XP, Inkscape 0.48.4 and trunk revision 12886 (but we now use a different renderer).
How long does that momentary state last? Do you run Inkscape on a slow computer? I haven't noticed any artifact, but I'm on a recent i5 cpu.

[Paul Kallnbach (p-kallnbach)]

I definitely experience the same behaviour on all computers in the office that run inkscape on multiple platforms. I actually had a look in the code because it felt so unnecessary and filed a bug about what I found

https://bugs.launchpad.net/inkscape/+bug/1267208

[Andrew Benson (spt112radaka)]

In response to jazzynico's questions.

The state duration seems to be dependent on the duration of panning. Usually the duration is between 0.1 and 1 second, but I've seen it last as long as 4-5 seconds (if I kept panning trying to extend the duration of the effect). The mouse scroll wheel results in the effect occuring for about 0.1 seconds for each tick of the scroll wheel.

My computer is a relatively fast computer, and I have a recent i5 cpu as well. I should bring additional attention to the fact that the artifacting happens regardless of file size or number of objects.

[Andrew Benson (spt112radaka)]

Also I'm impressed at the dedication shown in fixing bugs. Props to y'all!

[jazzynico (jazzynico)]

Tested again with Windows 7 (Virtualboxed) and Crunchbang Waldorf (a Debian stable based distro), Inkscape 0.48.4, on a core I5 computer.
On Windows 7, I clearly see some tearing when the object leaves a border of the workspace (see screenshot), but it doesn't last very long (maybe 0.1 second) and doesn't last even if I keep panning.
On Crunchbang it's even shorter, and I've had difficulties noticing it...

[jazzynico (jazzynico)]

Also tested with trunk revision 12886 on Windows 7, with the same result (very short tearing).

[jazzynico (jazzynico)]

@Paul, Andrew - Would you be willing to test a recent Inkscape development version from ftp://download.tuxfamily.org/inkscape/ and confirm it's also affected?

[Andrew Benson (spt112radaka)]

The bug is still present on inkscape-12904. I downloaded and tested the bug under the same conditions using that development version from the link you provided.

[su_v (suv-lp)]

Testing 64bit Inkscape 0.91 on Windows 7 (Intel HD Graphics 400), the tearing is much worse when using an Aero-based theme. Under Windows Classic theme, hiding the ruler (bug #1351597) does improve (i.e. reduce) the temporary tearing on-canvas during panning a lot.

As test case, 'car.svgz' from Inkscape's examples was used, and the new pan mode in 0.91 (spacebar pressed + mouse pointer movement).

The tearing observed on Windows during panning does not not happen with local builds of Inkscape 0.91 on OS X or Linux (Ubuntu 14.04, VM).

[Chainz (chainzee)]

Hi, I also have this problem, it's very irritating since it stays for a couple of seconds, even with super simple files.
I use version 0.91 on Win 8 with i7 processor, Intel HD 4600 graphics, 16GB RAM