Ubuntu
qtbase-opensource-src package

  1. Bug #1598173
  2. Comment #0

Comment 0 for bug 1598173

Revision history for this message
Elvis Stansvik (elvstone) wrote :

A fix for QTBUG-40889 was worked out and submitted at

    https://codereview.qt-project.org/#/c/115531/

but due to coming in a bit late, was moved to Qt 5.6

    https://codereview.qt-project.org/#/c/126136/

The bug is about mouse motion event compression malfunctioning, and it has grave consequences for some applications, where the flood of events make rendering sluggish (e.g. anything based on VTK, but probably others).

ParaView developer Ben Boeckel has tried the patch [2] and confirm it fixes rendering/interaction in VTK applications.

It is not possible to work around the bug at the application level in a satisfactory way, only by resorting to timer-based rendering.

I suggest an SRU to patch the Ubuntu Qt package with the patch that was originally meant for the 5.x branch (first URL above). The patch was later integrated in 5.6 where it has been well tested.

[1] https://bugreports.qt.io/browse/QTBUG-40889
[2] http://vtk.1045678.n5.nabble.com/Delayed-mouse-interaction-due-to-event-loop-bug-in-Qt5-tp5730474p5732870.html