You are not saying in which software you are trying to use RE:FLex but that says, say it’s AE
In AE, you use in a layer AE’s own rotomasks to control warping and morphing. The “FROM” and “TO” will alternate: as in your mask 1,3,5 will be FROM and 2,4,6,… will be TO. So if you do a Warp, you set in UnWarped Mode the FROM mask on the feature you want to warp, you duplicate it to have the same start point and you put yourself in WARP mode and then you move the points to get the proper deformation. The Checkbox to Auto-Hide will show you which one are part of WARP or UNWARP (source without modification).
Pierre
RE:Vision Effects