Dforce : where do props "fall" and how to control it?

odastein

Props don't necessarily fall towards trhe ground when subjected to Dforce. That's a problem I had repeatedly, so I'm going to give an example :

 

I create a primitive plane that is supposed to become a piece of cloth and put it above a character's lap, hoping that it will "fall" down and wrap her legs. But it"falls" to the side and wraps her arm and torso instead. 

Why does this happen, and how can I avoid it? 

Richard Haseltine

Probably a mix of the energy disipating through the mesh and the way the mesh is broken into triangles. Try increasing the number of sub-frames, see if that gives it more time to even things out and so avoid any excursions.

odastein

Richard Haseltine said:

Probably a mix of the energy disipating through the mesh and the way the mesh is broken into triangles. Try increasing the number of sub-frames, see if that gives it more time to even things out and so avoid any excursions.

I'll try that. 

Also, does it have anything to do with the presence of a character? If I hide the upper body of the character and there's nothing in this direction, will the plane still "fly" to the right instead of falling down? 

Richard Haseltine

If it's hitting the figure that may be a factor, yes, but not if it's clear of the figure until it lands.

yinliang9

You can use primitives creatively to sort of guide things, to a point. For example, if you're having a problem with cloth falling to one side, you could create a cube and place it at a slight angle in the path of the cloth, wherever it's "flying" to. With a little luck and some trial and error, this should be able to guide it to the lap. (Just make sure there's enough separation from the lap so that the cloth can fall around the legs properly, of course!

Additionally, you could try using a wind node at a low strength setting to give it a soft "tap" to offset the movement you don't want.