I created a small, pocket computer from Raspberry Pi 3 and small 4" display with resolution 480x320. It is very hard to do anything on such small screen, so I've been wondering, if there's a way to virtually enlarge screen resolution, such that if mouse pointer approaches one of its edges, screen scrolls. This is purely software feature, so shouldn't depend on the screen itself. Is it possible?
This feature is called "viewport panning" and it can be enabled using
xrandr --output default --mode 800x600 --fb 1280x1024 --panning 1280x1024
You still need a framebuffer large enough to fit the whole virtual screen, so you might need to set
If your screen comes with a custom driver, this will only work if the driver implements RandR extensions.
There are a couple of questions online regarding how to dynamically change your RPi's screen resolution. Here's an explanation on changing your screen's resolution without rebooting your RPi. This explains how to zoom out to fit the entire display on your screen.
To understand the different HDMI output formats check the official documentation on the video options in the
config.txt file. Here you can find additional information about this file.
You will probably want to run a script that changes these configurations without the need to reboot your RPi. Once you test out your script, you can configure your RPi to run it in the background every time you boot it.