I’m not sure, if this is what you are looking for, but you could bind a pointer–move event to your mode. It works fine for me in python.
Here is a quick test, I did:
def pointerEvent(self, event):
pointer = event.pointer()
sourceName = commands.sourceAtPixel(pointer)['name']
sourceGroup = commands.inputAtPixel(pointer)
imgPointer = commands.eventToImageSpace(sourceName, pointer)
pointer is a tuple with the x and y coordinates of the entire view
sourceAtPixel returns a list with a dictionary element (most likely just one)
inputAtPixel returns the RvSourceGroup Node
eventToImageSpace function returns a tuple, where the lower left corner of the image is (0,0), the height of the image is 1 and the width seems to be calculated according to the image aspect.