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1994rstefan
12th April 2013, 23:37
Hello,

currently i am developing an application for my Raspberry Pi. The Resolution of the screen that I use is 480x234.
The Qt-Application starts with "-platform eglfs".
The problem now is that the resolution is totaly messed up.
/dev/fb0 is set up correctly and returns the correct values. The Terminal looks also good.
I also tried to set the enviroment variables "QT_QPA_EGLFS_WIDTH" and "QT_QPA_EGLFS_HEIGHT" but that didnt helped. (Enviroment Variables found here: http://qt.gitorious.org/qt/qtbase/blobs/4f14b42f7dc289cd73a5e7aa934d6052c708bac3/src/plugins/platforms/eglfs/qeglfshooks_stub.cpp)

Could someone please help me on how to set the correct screen resolution?

thanks and regards

wysota
16th April 2013, 20:32
What resolution are you getting?

1994rstefan
17th April 2013, 18:35
Hello,

I found out that if I start the Application with "-platform linuxfb" it is using the correct resolution.

The Screen is connected via Composite. Here are two Pictures where you can see the problem:
This is how it should look(-platform linuxfb)
http://sdrv.ms/ZxJG6M

This is what it looks like (-platform eglfs)
http://sdrv.ms/14wd0CH

In Qt-Creator the size of the window/image is set to 480x234 (the resolution of the Screen)
But on the Screen it looks like it is using something arround 800x600 i think

The Problem why i cant use linuxfb is because i need mouse-support. (Touchscreen)
Or did i just miss that the linuxfb also supports mouse?

Amrutha
21st June 2017, 16:06
when i try to deploy qtwidget application , i am not getting anything dispalyed on the raspberry pi
it is displaying as

SSH is enabled and the default password for the 'pi' user has not been changed.
This is a security risk - please login as the 'pi' user and type 'passwd' to set a new password.

Unable to query physical screen size, defaulting to 100 dpi.
To override, set QT_QPA_EGLFS_PHYSICAL_WIDTH and QT_QPA_EGLFS_PHYSICAL_HEIGHT (in millimeters).

can you help me in how to set QT_QPA_EGLFS_PHYSICAL_WIDTH and QT_QPA_EGLFS_PHYSICAL_HEIGHT?