# Trouble with a modified parallax scrolling concept

I have a set of layers (each of them being a list of items) moving with different speeds as I mentioned here: https://stackoverflow.com/a/18962019/270197. Layers back in the scene move with slower speed than those in the front. The position of items in the front layer is calculated from VelocityTracker.getYVelocity() (we are not doing infinite scrolling but responding to the user's gestures) by using standard Euler integration with friction applied to decrease the velocity by a fixed number of percent each frame.

I would need a similar dynamics class for the background layers that act as a satellite, that is, movement should gracefully finish at the same time so instead of an abrupt pause, the velocity of the slower layers should dynamically adjust to the top layer's velocity on each frame (reaching 0 together) to create a realistic but synchronized fling movement on each layer. Any ideas about the algorithm to achieve that?

Update: it is implemented now on github.

layer_velocity = mVelocity * (1.0 - layer_depth)