Testing the water for more jruby integration

For some time now I've been thinking about implementing stuff in jruby java for ruby-processing. To that end I have forked yokolets Fraction class here. This could be a sort of half-way house where the guts could be implemented in pure java, but with a compiled jruby java interface, but I am sure I would do better with 100% jruby implementation of say my vecmath library (which currently is pure ruby). For performance, it is possible (but by no means a certainty to me) that SinCos lut tables would improve ruby-processing performance, but they will definetly need jruby java implementation to work. Charles nutter recently cited this as possible model for writing a jruby extension other people point to jrubies RubyEnumerable implementation.