is there a way for a QC comp to query in what environment it is being
run?
ie to find out if it is running as a quicktime or as a quartz
composition?
No, there's no way to do that that I can think of. The real solution to
that problem is to have compositions run with full features set in QT.
also useful would be the ability to find out if it is being run under
GWorlds or Visual Context for throttling effects or geometry to
maintain
a constant framerate?
There's no way to do that either. QuickDraw is officially dead since
WWDC 2004 and therefor GWrolds are going away - QuickTime Quartz
Composer supports them for compatibility reasons only.
Note that when run though GWorlds, compositions have a max framerate of
30 fps for obivous performance reasons, whereas in visual conctexts,
it's driven by the screen refresh rate
