Glyph images were rendered into a fixed 128x128 buffer and their width and
height were clamped to 128. Since glyphs are rasterized at the requested
scale (f96a14a0), large text such as title cards lost every row and column
past 128 pixels, so letters were drawn cut into bands.
The glyph buffers now grow to the glyph's bitmap box and width_byte is the
glyph's width. The VGA fallback font keeps its 128-pixel limit; scalable
glyphs are limited to 4096 pixels only to reject absurd scales.