[jitter] @capture to get a jit.gl.model to matrixoutput??

Does anyone have any leads on the capture attribute for gl objects? I  
have looked though the tutorial patches and html/pdf documentation and  
can't find anything. I am particularly interested in finding out how  
@capture works with getting a jit.gl.model to matrixoutput.... there  
is something in tutorial 36-37 but i can't make it apply to a obj  
model...... thanks, robbie