Is there a maximum size or can I use the full 240x240px?
It's just how much RAM you have available. 1bpp x 240 x 240 is 7.2k, which will fit in memory just fine. Even better if you do 240x192 to leave room for widgets.
That size at 2bpp would also be fine, but you just need to be a little careful not to try to allocate too much other memory :)
it would be nice to get the acual brightness or the default value from settings
As example an app could dim the brightness down for power saving and restore the user-set value by event or closing the app. So how can I get/read the actual state of brightness to restore it later (if possible)?
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It's just how much RAM you have available. 1bpp x 240 x 240 is 7.2k, which will fit in memory just fine. Even better if you do 240x192 to leave room for widgets.
That size at 2bpp would also be fine, but you just need to be a little careful not to try to allocate too much other memory :)
Not sure I understand?