[jmarshall]

The current implementation works by keeping the constants in memory so that they can be in another file (eg includes.xml). A preprocessor needs to know all this stuff, so it's easier just to do it whenever we lookup a float value.

This rules out booleans, DWORDs (a few timing variables - mostly for multiimage), and strings.

The implementation is done - just need to check it actually works as desired.

Cheers,
Jonathan