For developers working outside of Processing (e.g., with M5Stack), the M5Stack VLW Font Creator is a powerful web-based tool. It allows you to upload TTF/OTF files and select specific Unicode ranges to keep file sizes small.
Because VLW files are rasterized, never try to use textSize() to wildly scale a small VLW font up. If you need a font at 16px and 64px, use the converter to create two separate files: Font-16.vlw and Font-64.vlw . ttf to vlw converter