sumatrapdfreader
Pinch-to-zoom not working with Windows 10 and two touch screens
I'm running Windows 10 on a Surface Pro 4, with a Wacom Cintiq 22HDT external touch monitor. Pinch-to-zoom does not work at all on either screen. However, if I disconnect the Wacom, it works on the SP4 screen itself. *I realize it's not easy testing all these configurations, but I wanted to report the problem. *
With both monitors connected, touch panning is OK, long press (right click menu), and two-finger touch toggles full-screen. I'm not sure what the other touch features are supposed to be. So, it seems to be only a pinch-to-zoom problem.
It could be a Windows 10 problem, because Adobe Reader also has this issue (pinch zooming will only work on the SP4 if I disconnect my external touch monitor).
However, Drawboard PDF does not have this issue. Pinch zooming works properly on both monitors.
Unfortunatly without specific hardware,, issues such as above tend to relinquish without action, It helps to know if later updates to OS and hardware drivers, have an effect of negating such issues.
Probably not relavant (since there has been very little change in touch support) but helpful to know if the current pre-release still exhibits identical behaviour.
@GitHubRulesOK The issue still persists even today.
Is there any way you could code this into our SumatraPDF-Plus program? I would owe you the world Im using Windows 11, on a Surface Pro 9 (tablet)
I am not the developer and overall the problem is hardware specific needing a touch monitor (and touch programmer too) the underlying issue is the way images are rendered on the screen from window canvas top left origin
the touch at 2 points in screen center needs to be averaged say 1" left of center that then needs translation from glass position to window position to page position then the zoom factored by multiply current and target scales based on space between fingers on a constant basis. it is significantly more complex than just respond to a system directive to scale in or out around the top left corner.
It's an old request and I can't fix it because I don't have a way to reproduce it.
Someone with access to this hardware and ability to debug software would have to debug OnGesture in Canvas.cpp to try to figure out why it doesn't work.
It's possible our zoom handling is slightly incorrect but the bug only triggers in this combination.
