Arundina fonts were created under SIPA's initiation, aiming at Bitstream Vera/Dejavu compatibility. They were then further modified by TLWG for certain aspects:
* Latin glyph size compatiblity. That is, Latin glyphs should have equal size with those from Western fonts at the same point size, so that it would not require users to scale fonts when using them together in the same documents.
* OpenType conformance. Similar to the ThaiFonts-Scalable project we have done, we attempt to fullfill OpenType requirements for Thai fonts, according to our drafted spec. However, as many applications, including MacOS before Leopard and Adobe before CS3, do not support the Thai-specific features well, the 'liga' GSUB hack developed by the original author is still retained for the time being.
We use FontForge as development tool. You need it to generate fonts from the downloaded source.