Dynamic locators follow the motion of the pond in the Y direction, but additionally react appropriately to dynamic attributes (in the Extra Attributes section of the Attribute Editor).
If you want to move the position of the locator interactively, the locator cannot be connected directly to the expression. In this case, turn on Free Transform.
Except where otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License