Bandu

that's great, thank you !

this method calculate always the center point, I want to use $XMAX, $BBX and all other variables and expressions using this variables, like is standard Houdini transfer node. At the same point it will allow me to create my own local variables if I only knew how to declare them. Thanks anyway!

Hi guys, I'm doing a VEX SOP Geometry Operator and I'm wondering if there is a way to define my own Local Variables like $CEX $CEY $CEZ for example. I want to be able to use them in my Parameter node if possible. In detail, I needed different type of Scale Operator I wrote and it works fine. I need to compute my geometry center in order to work it properly. The only way I found is to type my previous transformation in Parameter node ( if the geometry is transformed ) and use this values inside VEX. In Houdini Transform Operator I can type $CEX, $CEY, $CEZ to get the center of the object ( origin for scale ) or any values I like. Now I need the same Local Variables for my Operator ( even $XMAX... $BBX... ) so it will compute them automatically inside my own Operator as soon as I write them in my parameter dialog. Thanks, Bandu

as your grid2 is moving, calculate velocity with the trail1 before cookie1 and it works fine... Bandu inheritedVelocity_bandu.hipnc