[Qtwebengine] Possible bug in touch event coordinates in QtWebEngine when using pixelDeviceRatio

Allan Sandfeld Jensen allan.jensen at theqtcompany.com
Wed Oct 14 16:59:39 CEST 2015

On Wednesday 14 October 2015, Christophe Chapuis wrote:
> Hello folks,
Hello there

> First, I'm sorry I didn't see that this specific mailing list for
> QtWebEngine existed; that's why I first posted my message on development
> ML. I will from now on stick to the qtwebengine ML.
> I am currently working towards using QtWebEngine for our project (LuneOS),
> and I stumbled upon an issue. I am using the experimental devicePixelRatio
> property in the QML WebEngineView component, so that our html page is
> displayed nicely on mobile device with high DPI.
> However, I remarked that when using devicePixelRatio, only a part of the
> webpage was responding to touch events on device. Therefore I suspected an
> issue in the conversion of touch event coordinates, and found out that
> touch events don't seem to be mapped to web coordinates using dpiScale.
> I did this modification, and now it seems to be working fine:
> https://github.com/webOS-ports/qtwebengine/commit/ec0a2f759cd1fb2675ae6f761
> c6172004cf8af23
> Do you agree with this modification ? How could I push that upstream ?
There is a few things that could be improved in the patch, but it looks good. 
It would be great if you could make a bug-report and push the patch to Qt 


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