Module: Eval On Spatial Graph ()

Description:

This is an experimental module from the Xtra Library: https://xtras.amira-avizo.com.

The Xtra takes an object of type Spatial Graph and a uniform scalar field as input. The field is evaluated at each point of the Spatial Graph and the result is stored in a copy of the input Spatial Graph, as thickness (radius) attribute.

A common usage of this module is to connect a skeleton and the distance map used to compute this skeleton, so that each point of the skeleton includes a thickness information.

This Xtra is similar to the Eval On Lines module, except that it doesn't modify the distance map when it is a chamfer map. The Xtra also offers two additional options compared to Eval On Lines. The first option consists in capping the thickness with a maximum value. The second option consists in appending only decreasing values to the thickness attribute of a segment.

This second option is of interest for example when considering a flow in throats. The information of smallest radius of each throat will be propagated along each Spatial Graph segment, therefore indicating where the flow ends in each throat.

Connections:

Data [required]
The Spatial Graph object.

Field [required]
The scalar field to sample, e.g. the distance map.

Ports:

Max Thickness

Maximum value to cap the thickness attribute. By default it is equal to the input scalar field maximum value.

Decreasing

If checked, only decreasing values of thickness are appended to the thickness attribute of each Spatial Graph segment.

Interpolation

Mode of evaluation of the field at each Spatial Graph point. The Nearest Neighbor mode returns the data value at the nearest grid point. The Standard mode interpolates the data at the point.