AdnRigidWrap
AdnRigidWrap is a Houdini SOP that transfers deformations from one or more target geometries to an input geometry using a closest-surface attachment model.
For every point of the deformed geometry, the deformer searches for the closest point on the closest surface of the connected target geometries. Each input point is attached to its corresponding target surface point, preserving its relative position as the target geometry deforms.
AdnRigidWrap is particularly useful for attaching secondary geometry to deforming surfaces, transferring deformations between unrelated meshes, and creating rigid surface-following deformation setups. It is also a core component of the AdnTransfer Tool, enabling the transfer of fascia and skin anatomy between character models.
How To Use
The AdnRigidWrap is easy to create and configure in Houdini. It requires the mesh to apply the deformation onto and the target(s) that will drive the deformation.
- Go to the geometry context of the rig containing the geometry to apply the deformer to.
- Press TAB and navigate to the submenu Adonis > Deformers to find the AdnRigidWrap
SOP type. - Create it and connect the geometry to the input.
- Go to the Targets tab in the AdnRigidWrap parameters, add a new entry to Targets to add a geometry target.
- Provide the object path of the target geometry in Target World Mesh.
Attributes
Time Attributes
| Name | Type | Default | Animatable | Description |
|---|---|---|---|---|
| Initialization Time | Time | Current frame | ✗ | Sets the frame at which the deformer will be initialized. |
Deformer Attributes
| Name | Type | Default | Animatable | Description |
|---|---|---|---|---|
| Envelope | Float | 1.0 | ✓ | Specifies the deformation scale factor. Has a range of [0.0, 1.0]. The upper and lower limits are soft, values can be set in a range of [-2.0, 2.0] |
Maps
| Name | Type | Default | Animatable | Description |
|---|---|---|---|---|
| Weights Attribute | float | 1.0 | ✗ | Specifies the name of the per-point attribute to read the weight of the deformation. The expected attribute name is adnWeights. The expected range of the per-component per-point values is [0.0, 1.0]. |
- All maps parameters are disabled in the Maps tab because the attribute names are fixed to drive specific functionalities of the solver.
- Fixed point attribute names also ensure compatibility with the API.
- To copy the map names of the disabled attributes for painting (using an attribute paint node) right click on the disabled map attribute parameter, press "Copy Parameter", select the attribute paint node and on the attribute name entry right click and press "Paste Values". This allows to easily copy the attribute name for painting.
- The Make Paintable utility provided in the Adonis menu > Utils, can be used to create the attribpaint node and automatically populate the entries with the map names of the AdnRigidWrap SOP.
- If a point attribute on the geostream does not match the naming convention exposed in the node, use an "Attribute Rename" node to rename the attribute to match the expected naming convention.
Parameter Template
Paintable Weights
| Name | Default | Description |
|---|---|---|
| Weights | 1.0 | Global weights map used to control the influence of the deformer at each vertex. |
To tweak the point attributes of an AdnRigidWrap SOP, an
attribpaintis needed. To ease the creation and initial configuration of this node, select the AdnRigidWrap SOP and click on Adonis > Utils > Make Paintable. This utility will create anattribcreatenode to define the required point attributes and assign their default values followed by anattribpaintnode to allow these attributes to be modified. Both nodes are automatically named and properly connected to the AdnRigidWrap node.
