Use the Save Screenshot function in the Viewer window
Compile the Image Writer plugin from the XCode project in Developer Examples/Quartz Composer/Plug Ins (or some similar location- can't remember the exact path, and I can't check right now, as I'm not in front of a machine with Leopard installed).
There's all sorts of interesting stuff in the Developer/Examples folder.
There are already several ways to do this.
There's all sorts of interesting stuff in the Developer/Examples folder.
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