Houdini 20.0 Nodes VOP nodes

Compute Normal VOP node

This node gives finer control over handling of the normal attribute in VOPs.

Typically, when VOPs cook geometry, the SOPs will try to do the right thing with the normal attribute. That is, if the P attribute is modified, the normal attribute will usually be out of date. The right thing is usually to re-compute the point normals whenever P changes (provided the VEX code doesn’t modify N on its own).

However, in some cases, you may want finer control over how the normal attribute is handled. There are three possible choices provided:

  1. No modification to N:

    The VEX code will leave the N attribute unchanged.

  2. Re-compute N if P changes (default):

    The VEX code will recompute the N attribute, if the P attribute is changed.

  3. Forcibly recompute N:

    The VEX code will recompute normals, regardless of whether P is modified.

VOP nodes