I have some processing code that works on double precision arrays that I'd like to visualize using an NSImage. I thought I could be clever and just use the NSBitmapImageRep data buffer directly, but it doesn't seem to support double precision values. I can get it to accept 32 bit floats, but not 64 bit doubles. Now, I could keep a separate buffer of doubles, and then resize them all to floats for display but I'd like to find a better way. I think the answer is a custom NSImageRep, but I'm having a hard time finding an example of one that draws bitmaps. In particular, how to implement the -draw method. Do I draw a colored rectangle for each pixel or is there a better way to transfer bitmap data? Anybody have a better idea of how to do this?