Blog

1st March 2017. We have had several requests from customers to provide a way to allow Carbon cloth to be shaped by other Houdini solvers. So after some head scratching, we wanted to share with you a sneak peek of an exciting new feature we are developing for Carbon Cloth. This "Override" feature allows the cloth position to be overridden by the position of another mesh, on a frame by frame basis, in one of two ways.

1)  Pre-override - where the target mesh is provided to the solver, which then attempts to move the cloth to the target position, but within the limits of the cloth mesh constraints. In this case the result is physically correct, but the cloth may not reach the target position during the frame.

2) Post-override - where the target mesh is used after the cloth solve on a given frame to move the cloth mesh positions to be the same as the target mesh positions. In this case the resulting cloth will match the target, but will not be physically correct and there will likely be some cloth mesh distortion. Also need to be careful not to infringe collision and self-collision.

The target mesh can come from anywhere and can for example be generated by other Houdini solvers.

Below is sneak peak video from our development test bed showing the Override in action.

  • All the cloth movement here is coming from the solver trying to match the cloth to the target mesh. 
  • The target mesh is represented by the white dots and when the cloth is green, pre-override is being used and when the cloth is red, post-override is activated.
  • Note how the red cloth and the white dots are always in the same place, but the green cloth and the white dots are not.
  • The target mesh control is on a per frame basis and so the white dots are never too far out of position relative to the cloth as that is the distance you are aiming to move the cloth in just one frame.
  • The override is applied on a frame basis, so it can be used or not used or switched seamlessly from pre-override to post-override as shown in the example.
  • In this example the override target mesh white spots is generated by a displacement algorithm using the current pose of the cloth and a simple animated field (orange dots). The override target mesh can be provided in many ways.

We still have to figure out how to integrate this into the Carbon plug-in for Houdini, so it will be a few weeks before it gets into the product - but its coming....