changing vert order wrap

[dan2266]

Hi Guys,

 

I'm new to houdini, and I'm I'm trying to wrap (I'm from a maya background, not sure what the houdini equivalent would be. I read lattice SOP in point mode  in a couple of threads before) an object to another. Basically control the surface points of one object by the surface points of a deforming object. The problem is that the deforming object has a different vert order on every frame.

The main purpose would be having a series of 3d scans which capture a motion frame by frame, and binding a working topology to them so that it inherits the surface point positions of the whole sequence, frame by frame. I used another software's optical flow wrap based on texture correspondences till now, figured there might be another solution in houdini.

Like having a per frame sequence of a model going from a neutral expression to a smile, binding my geo to the first frame, end letting the per frame scans deform it so it can be used in an animation rig. I trying to unify the point count with a scatter node and export a unified alembic to wrap to, but of course since while being blendable, the points don't maintain their respective position on the surface I got a lot of sliding around on the surface. Not sure if it makes sense, or if there could be some houdini trick/workaround that could help.

 

Thanks,

 

Dan

 

 

[bhouse]

I'm not sure I exactly understand what you are trying to do, but you can use the Ray SOP to deform geometry based on another geometry with different point counts.

ray_deform.hip

[dan2266]

4 hours ago, bhouse said:

I'm not sure I exactly understand what you are trying to do, but you can use the Ray SOP to deform geometry based on another geometry with different point counts.

ray_deform.hip

Thanks Ben!

this is kind of what I wan't, except I'd want the verts of the driven object (the box in this case) to stick to the driver object. Now it seems they're projected on frame by frame, sliding on the surface of the object,  while the sphere with the mountain appears to be rotating.

[Noobini]

Pointdeform ? (or in Max terms, skinwrap)

[dan2266]

1 hour ago, Noobini said:

Pointdeform ? (or in Max terms, skinwrap)

that'd be the one, except, would that work with the deforming object having different vert count and vert numbers on every frame?

[Noobini]

7 minutes ago, dan2266 said:

that'd be the one, except, would that work with the deforming object having different vert count and vert numbers on every frame?

oh bummer...that would throw a spanner in the works then

[dan2266]

9 minutes ago, Noobini said:

oh bummer...that would throw a spanner in the works then

ye... not sure if there's a workaround, currently I'm using optical flow wrap since I do have matching textures (no matching UVs though) on the source and target object. But it's slow and tedious, so I was thinking maybe there's anything in houdini that could do the trick. Like fluid sim (cause they usually have varying vert count), constraining a boat to an ocean wave, except the boat is every vert one by one and the ocean is a scan sequence of an actors face... Don't know, just brainstorming... I have a feeling there no easy option.