compressed fonts: a proposed format

Here is a suggested description of "ZOT", a compressed font format  
intended for Web-font use. This is designed to be "lightweight" in the  
sense that it will be simple to implement, both at the producer and  
consumer sides, and add minimal extra code to browsers; this is  
achieved primarily by using an existing compression library rather  
than a custom algorithm.

The compression achieved with this format will depend exactly which  
compression library is chosen (this is still to be decided); it may  
not be as good as can be achieved by a font-optimized approach like  
MTX, but I believe this approach has other advantages that may make it  
a better overall choice.

IMO, it should be simple for browser vendors to support linked fonts  
using this format; if they need a "complete" font to hand to an  
existing text API, the original OpenType font can easily be  
reconstructed in memory, and if they want to access font tables  
individually from the compressed file, this is very similar to doing  
so with a standard OpenType font.

I'm happy to discuss details of this format, but please, let's keep  
that discussion separate from the question of whether using a font- 
specific compression method (independent of whether we ultimately  
choose something like MTX or something more like ZOT) is the way  
forward for interoperable web fonts. If we can agree that the overall  
approach is acceptable, then potential implementers can discuss the  
technical details of formats, separate from the social, legal and  
political aspects.

Jonathan