Houdini 19.0 Nodes Geometry nodes Volume Stamp

Volume Stamp geometry node

Stamps volumes instanced on points into a single target volume.

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Since 12.5

The Volume Stamp operation takes a cloud of points and instanced volumes onto it, and then stamps the result into the target destination volume.

Parameters

Destination

Which volumes or VDBs in the first input to stamp into. If no name attribute is present, there should be a single volume or VDB and is treated as the “density” target.

If more than one is present, a name attribute should be present. The name is used to compare with the volumes cooked in the third input.

All of the destination must be aligned and of the same time (vdb or volume).

Stamp Points

A group of points in the second input to instance volumes onto. All the normal instancing attributes will be used, matching the behavior of the Copy SOP with transform points turned on.

Merge Method

How to blend each incoming volume in with the base grid. Because it is not defined what order the volumes will actually be stamped in, this must be symmetric.

Samples per Voxel

If stamping high resolution volumes into a lower resolution volume, aliasing artifacts can occur. To avoid this, you can make more than one sample per destination voxel.

If this is 1, no random sampling is done, instead a single sample is done in the middle of the voxel.

Sampling Seed

The seed used for generating the random samples.

Premultiply Input by Density

The generated attributes other than density will be multiplied by the 'density' field, if present. This allows for proper mixing of normalized fields such as colour or velocity.

Normalize Output by Density

Divide the generated fields by the density field to undo the effect of the premultiplication pass.

Number of Stamps

To provide variety in the sorts of volumes stamped, you can have the third input be controlled by stamp() expressions. This controls the number of point attributes from the second input that will be promoted for stamping.

Note

All identical stamp values are collated for a single cook of the third input to minimize the number of cooks required if there are duplicate point attribute values.

Enable Stamping

Turns on stamping of this particular attribute.

Attribute

A point attribute on the second input.

Stamp

The name of the stamp variable to access with the stamp() expression. If blank, the attribute will be made ALL CAPS and used.

Examples

GridStamp Example for Volume Stamp geometry node

This example shows how to use the Volume Stamp SOP to copy volumes onto the points of a grid.

See also

Volume Stamp