It seems that grab function in kangaroo can only grab one vertexes. But in reality, human hands can have many touchpoints on the object( I mean the touch area is not just a point but a surface). is there any way to let grab function control more vertexes so it can be more natural? or is there any other way to do it?
You could use a sphere or almost any other geometry for collision and push this object into your mesh
It’s an interesting question - I know the single point grab can be limiting and I have thought a bit about ways to improve this.
If there are any particular scenarios you can describe, or how you would want it to work that could be helpful.
As Martin says, you can currently use a sphere to push meshes at more than one point (here’s an old example of this Sculpting plastic mesh with Kinect and Kangaroo on Vimeo), but at the moment it’s hard to pull or drag multiple vertices.
You can also use combinations of edge lengths, smoothing, plasticity etc to allow dragging meshes without creating sharp points, even though the mouse is only actually selecting one point at a time (see here for an example BowlSculpt on Vimeo)
However, I think it might still be useful to have other ways of dragging multiple vertices.
Two possible directions I’ve considered for this are:
-Windowed selection of multiple points, then treating the selected points as a rigid set while you drag them. This is quite tricky to do in terms of all the mouse interactions, and I’m also not sure it’s even a particularly useful way of manipulating simulations.
-Mesh grabbing with a falloff. So a region of the mesh around where you first click would get pulled with strength decreasing as some function of distance (this distance could be defined in various ways - distance in space, distance on the mesh, or topological distance).
There are also some interesting questions here about what should happen to the orientation of the dragged region.
@DanielPiker Hi Daniel, thanks for your reply! Indeed, pushing can be done by collision, so the hard thing is pulling or dragging multiple vertices. I got stuck in the pulling simulation, something like pulling out of the rubber cap of a can would be hard to be done by controlling a single vertice. The videos you shared were interesting and enlightening.
As a dilettante, I personally suppose the second direction would be more natural, may like the brush function in some softwares(maybe ZBrush?) I even figured out the future modeling and doing simulations by pretty natural actions such as push and pull with some technology like kinect. That really redefines how people think about computer-aided modeling can be like. Again thanks for your reply~~ Hoping that kangaroo would be more stunning in the future.
@martinsiegrist Thanks martin, that is very smart indeed.