Using image sheets with graphics.newMask()

I’d like to use an image sheet frame with graphics.newMask() instead of an image filename. So instead of:
[lua]
myMaskPtr = graphics.newMask(“myMask.png”);
[/lua]

I’d like to use something like:
[lua]
myImageSheetPtr = graphics.newImageSheet(“myImageSheetMasks.png”, mySheetData);
myMaskPtr = graphics.newMask(myImageSheetPtr, 2);
[/lua]

Any ideas? Is it possible?
[import]uid: 133169 topic_id: 37631 reply_id: 67631[/import]