Proportional bitmap fonts

Here’s a method for producing proportional bitmap fonts. The red component defines the drawable area for each glyph. Green defines the actual appearance. Blue defines the origin and spacing. Blank glyphs are skipped.

Layers are used to define groups of characters, allowing any part of the unicode codespace to be specified. A layer name with a single code point defines a sequential group. Ligatures are possible by defining a layer name with more than one code point.

Text is rendered by placing the left-most blue pixel of a glyph over the right-most blue pixel of the previous glyph. Using a baseline instead of boundaries for glyph placement allows glyphs to be spaced arbitrarily, and even drawn over each other.