I have recently changed my laptop to one with higher screen resolution, but I find that the GUI windows (TBrowser, TCanvas, …) have become much smaller as a result.
I have tried changing the GUI parameters in system.rootrc without luck.
Maybe someone has had similar issues and can point to a solution?
First of all, welcome to the ROOT forum! In regards to your question, could you please paste here the lines that you added in your system.rootrc file?
Regardless of ROOT-specific settings, increasing the DPI value for your screen (typically defaults to 96 on most OSes), should make the change system-wide, i.e. all your application windows should appear larger.
Basically, what you have specified is a X11 logical font description string. The availability of these sizes can be queried using the xfontsel program of your X11 distribution.
I think it is better to enable Xft (X FreeType) support. Adding the following line to the rootrc should make it:
X11.UseXft: yes
Additionally, I think that the font names have to be changed to a Xft string, e.g. times-14. Some users reported that this does not work properly in their scenarios. If that does not solve the problem or you face any other issue, please reply here.
There is not much we can do more than increasing the font size. The problem will be solved with the ROOT 7 (Web) GUI. You can try for example:
root [0] #include <ROOT/RBrowser.hxx>
root [1] using namespace ROOT::Experimental;
root [2] auto br = std::make_shared<RBrowser>();
Info in <THttpEngine::Create>: Starting HTTP server on port 9410
root [3]