GNUStep Alternative to CGImage

[Justin Kendrick]

I'm trying to write an open-source clone of Core Animation to use with  
GNUStep.  Of course, CA's interface is fairly highly coupled with  
Quartz/CoreGraphics, mainly in its use of CGImage to pass image data  
in and out.  NSImage seems heavier-weight, with its representation  
system, but I don't know if NSImageRep is really suitable for that.   
Does anyone on the list have more perspective on this?