Just a perk, which I wish HD44780 had for regular characters, you can see inverted characters after reading inverted for a while but they're poor to begin with. The best inverted characters are displayed using rows 1 and 2, while rows 0 and 3 are filled black boxes, like the hello. The point of the big fonts is to be able to see the normal characters from far away.
If you have a 20X4 display you could probably use all 4 rows to display 4 numbers in good resolution, with 57 dot matrix font. With two rows and three columns it's the best I could come up with, which is 35 dot matrix font.
I'm only wanting to display numbers and a decimal point (for temperature display on a 16x2), is it possible to change the custom characters used in the library for a "rounded style"? - I haven't quite got my head around libraries yet...
Actually not possible. I made a trade off ugly looking for displaying all symbols. Each character is a 3*5 matrix of dots so you can't have one dot that is rounded on the bottom left and another on top left. There are other libraries out there that only do numbers with rounded corners and possibly dot and colon. Good luck!
I found a nice font (actually a few) but, for my coding skills they're not really usable.
I want to be able to, effectively, do
bigLcd.print((char)223); // nice but optional
bigLcd.print ('C'); // nice but optional
within the sketch to display a temperature reading. Everything I've found so far takes individual numbers, breaks them up into bytes and calls them that way (as far as I can tell) and that's just way too complicated for me to fathom out - that's why I was looking for a library.
I understand. My library is offering that (send string to display) but font isn't too good looking. Have you looked at my super font with 5 lines width? It looks better but needs 20x4 display for 3 characters.