Ruler delay leads to slow live input on tablet

[Sean K]

Windows 7 x64
Inkscape 0.48.4 r

Using a tablet (Wacom Bamboo) tablet input produces very slow live-preview of both Calligraphy and Pencil tools. This goes away when the screen is small, so it is only present in full-screen views.

While trying to track down the source of live preview delay in Inkscape I ran across mostly bug reports/forum threads about lack of tablet input alltogether. Some threads existed for slow input on Ubuntu.

The fix I found was to disable the ruler toolbar. In full-screen views disabling this gives instantaneous live views.

I also noticed that when using the tablet, there were in some cases a lot of viscoelasticity to the ruler that is not present in mouse mode. By this I mean that the ruler coords move precisely when the mouse moves, but when the pen moves the ruler coords move VERY SLOWLY at the start and then pick up speed to match the current position. If the pen moves indefinitely the coords will catch up, at which point the live view will update the "buffered" path and then the whole process will start over. Again this isn't true all the time, and even when the ruler IS tracking the pen position in real time the live view still has a huge delay.

[su_v (suv-lp)]

Similar observation wrt to ruler mentioned in
- Bug #987593 “Bezier tool is slow in Inkscape-trunk” (comment #5)

Another report wrt update of GUI elements slowing down certain tools if using a tablet:
- Bug #671536 “Pen (Bezier) tool is extremly slow”

[Sean K (stkelly85)]

It is likely this is actually a dupe of those bugs but I made this one new as the existing bugs revolved around Ubuntu (or Linux in general) as did some of the suggested fixes.

[jazzynico (jazzynico)]

@Sean K - The rulers code has been recently updated to fix performance issues on Windows. Would you be willing to try a recent development version [1] and confirm it your issue is fixed too? Thanks!

[1] Please download the most recent file from ftp://download.tuxfamily.org/inkscape/win32/

[Sean K (stkelly85)]

Unfortunately I don't have access to the hardware (tablet) any more to test
this. Also it's been long enough since I noticed the bug that I don't
really recall how to make it happen!

Apologies,
Sean
On Mar 31, 2016 9:11 AM, "jazzynico" <email address hidden> wrote:

> @Sean K - The rulers code has been recently updated to fix performance
> issues on Windows. Would you be willing to try a recent development
> version [1] and confirm it your issue is fixed too? Thanks!
>
> [1] Please download the most recent file from
> ftp://download.tuxfamily.org/inkscape/win32/
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1272488
>
> Title:
> Ruler delay leads to slow live input on tablet
>
> Status in Inkscape:
> New
>
> Bug description:
> Windows 7 x64
> Inkscape 0.48.4 r
>
> Using a tablet (Wacom Bamboo) tablet input produces very slow live-
> preview of both Calligraphy and Pencil tools. This goes away when the
> screen is small, so it is only present in full-screen views.
>
> While trying to track down the source of live preview delay in
> Inkscape I ran across mostly bug reports/forum threads about lack of
> tablet input alltogether. Some threads existed for slow input on
> Ubuntu.
>
> The fix I found was to disable the ruler toolbar. In full-screen views
> disabling this gives instantaneous live views.
>
> I also noticed that when using the tablet, there were in some cases a
> lot of viscoelasticity to the ruler that is not present in mouse mode.
> By this I mean that the ruler coords move precisely when the mouse
> moves, but when the pen moves the ruler coords move VERY SLOWLY at the
> start and then pick up speed to match the current position. If the pen
> moves indefinitely the coords will catch up, at which point the live
> view will update the "buffered" path and then the whole process will
> start over. Again this isn't true all the time, and even when the
> ruler IS tracking the pen position in real time the live view still
> has a huge delay.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/inkscape/+bug/1272488/+subscriptions
>

[jazzynico (jazzynico)]

No problem, thanks for reporting back!