[Interest] Input Latency Issues in QtQuick

[Willem Bennekom]

With its current architecture, QtQuick has input latency issues:
The scene reacts to user input with a slight, but noticeable delay, which
makes
QtQuick apps feel clumsy and unpleasant to use.

I guess this is related to vsync handling, where input events don't
immediately
trigger a repaint while the render thread waits until the framebuffer is
swapped.

The only exception are Windows platforms with native OpenGL on ATI cards,
where the framerate seems to be uncapped:
The rendering is super responsive, almost like Qt Widgets.
The drawback is that render thread animators are broken, as they aren't
synced to 60 Hz.

1. Is there a way to hack Qt to get this Windows+OpenGL+ATI rendering
behavior on all platforms?
   Maybe some tweaks in qsg*renderloop.cpp?

2. Are there plans to implement a rendering scheme that reduces input
latency?

Thanks
Willem
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