gtk:snapshot-push-cross-fade (snapshot progress)

snapshot -- a gtk:snapshot object
progress -- a number coerced to a double float for the progress between to 0.0 and 1.0

Snapshots a cross-fade operation between two images with the given progress. Until the first call to the gtk:snapshot-pop function, the start image will be snapshot. After that call, the end image will be recorded until the second call to the gtk:snapshot-pop function.

Calling this function requires two subsequent calls to the gtk:snapshot-pop function.