Draw home screen with GFX library instead of loading background image #7
Description
The home screen is currently drawn by loading a BMP from SD card. The reason was that I wanted to have things like "°C", "g/m³" and the German "ß" there which are not available in the fonts delivered by Adafruit, and extending the font would have increased the size quite a lot.
The alternative solution is to draw everything using the GFX library except these things, and to create bitmaps for them just as we do for the icons and place them this way on the screen.
This would rendering the home screen make much faster and remove the necessity to design the home screen outside of the program with a different tool.