The new positions of each of the paths is applied to the curve controlled by the Morphius object. Currently, advance cycles from 0 to 1 and then back to 0. This behaviour will most likely change in the future to be more flexible. This is used to show the controlling paths on screen. After each controlling path's position is updated, the new positions are applied to the path controlled by the Morphius object.
Properties prefix is an array of strings.
When a Morphius object is created, the template is divided into separate strings using the pound sign as a delimiter. Each of these strings is stored in the prefix array. Each path in the array is used to control various points in the template. There is one path for each pound sign in the template. This defaults to 0.