It is possible to work with 2 x and 4 x concurrently. It allows to selectively enable or disable certain rasterizer features like, e.g., hinting. - xglyph extended to support 4 x antialiasing. It allows to set a default encoding vector which then is applied to all subsequently loaded fonts that have StandardEncoding. The format of encoding files is extended correspondingly and is backward compatible. Moreover, kerning pairs need no longer be alphabetically sorted.
Scanner is now aware of pfb-blocks and can scan files with multiple binary data segments.
This is an incompatible change to previous versions, but I think it should be worth it. The switchlimits are adjustable. This allows interfacing with other path search systems like kpathsea. This might be experimental because I don't know the rules for this exactly. This is an incompatible change with respect to V. 0.8.