scale is the Parameter that controls how large of a Canvas you have to work on. Scale does not affect physics, so everything will behave as expected. When the Parameter scrollFlag is enabled, scale can also be used as a way to "zoom" in on particles. First you must pause so that your creation does not get pushed over the edge if you move the screen, then you can change scale so that you can see better and work easier, then you must change scale back to the previous value, re-center your creation if you moved it, and unpause.