Does building each Trinity package depend upon having the previous package in the build chain installed?
For example, do I have to have the Trinity version of kdelibs installed to build kdebase?
Or can I build each Trinity package on my stock KDE 3.5.10 system?
No, each Trinity package must be installed before the next can be built. The include files have changed dramatically from KDE3.5.10 due to the new features (e.g. the new low level libkrandr library) and also due to the TQt conversion.