I'm using the AdaFruit ILI9341 libraries. with a 240x320 display. Small fonts are fine, however when using for example font size 5, some characters an "X" and "Z" are good example of the blocky apperance.
I tried unsuccessfully to get the PaulStoffregen fonts library working but it does not appear to work at least not with my setup and MKR Zero.
Does anyone know of a working MkrZero / ILI9341 fonts library with nicer looking large fonts or suggestions on a solution.
Much appreciated, Jester
The blocky appearance is unavoidable when using font size to make a font larger, all that does is turn each pixel into a block of pixels. As in your example of font size 5, each pixel will display as a block that is 5 pixels wide and 5 pixels high.
To get a good looking large font, the font needs to be large to begin with, so that a font size of 1 can be used. This will require a large amount of memory to store, unless you only need a few characters.
If you want a large font, there are online tools for generating the Adafruit GFX formatted font file from a truetype font (ttf file), as well as a fontconvert utility that is in a subfolder of the Adafruit_GFX_Library.
The fonts used by Arduino libraries & displays are not like the fonts you are used to on a PC.
On PC (Windows, Mac, Linux) the characters in a font are "glyphs". Glyphs are shapes that could be made with a writing implement of some kind, and their shapes are described mathematically: lines, curves, dots etc. When text is drawn on a LCD/OLED screen, those shapes must be converted into an array of pixels. With the large memory and fast processing of a PC, this can be done "on the fly" and the result is that when you increase the font size, the glyphs are converted to larger pixel arrays and retain their smoothness.
Arduino don't really have the memory and processing speed to do this, so all the characters in a font are provided as pre-rendered pixel arrays. This looks ok when printed using a small font size, but if you enlarge them, all that happens is that those pixels are drawn larger, and the font no longer looks smooth.
david_2018
Can you point me to the online tool or a link on how to?
I actually only need a few characters: X, Y, Z and G
Thank you
There is truetype2gfx https://blog.adafruit.com/2021/11/04/truetype2gfx-converting-fonts-from-truetype-to-the-adafruit-gfx-library-for-arduino/
Not really familiar with any online tools for removing unneeded characters, but I have seen some discussions indicating they exist. Editing a GFX font file manually is not something that is easily done.
Which particular font are you using? The default font is based on the code page 437 font, not sure if that is available as a truetype font.
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