Vertex surface node

Manually adds or edits attributes on vertices (rather than on points).

All

Parameters

Local variables

This node is similar to the Point SOP. It supports two inputs, and will inherit the first input source by default.

There are currently three vertex attributes supported: Diffuse Color, Alpha and Texture Coordinates.

When the attribute is defined, it can only occur on either points or vertices, but not both. Thus, if the input geometry has a point attribute for diffuse color, the attribute will automatically be “elevated” to be a vertex attribute (if diffuse colors are added in the Vertex op).

The op processes every vertex of every primitive. For each vertex processed, there are variables which allow you to know the:

a) Vertex number of the primitive being processed b) The number of vertices in the primitive being processed c) The point which is referenced by the vertex d) The primitive which contains the vertex e) The total number of points f) The total number of primitives

There are also local variables to find out the values of some point attributes (i.e. position, normal, if they exist), in addition to vertex attributes. See Locals section below.

Example

Example of manipulation:

vertex/cr = $BBX
vertex/cg = $CG2
vertex/cb = $CB - $CB2

Parameters

Group	Subset of primitives whose vertices are to be affected.
Color	Diffuse color (RGB)
Alpha	Transparency value
Texture	Texture coordinates
Crease	Crease weight for polygonal subdivision Use the Primitive operation to create a crease of constant weight for the entire primitive.

Local variables

PT, NPT	Point number and total number of points.
PR, NPR	Primitive number & total number of primitives.
VTX, NVTX	Vertex number & total number of vertices.
CEX, CEY, CEZ	Centroid of the geometry.
BBX, BBY, BBZ	Relative position of point within bounding box. Values are mapped between 0 and 1.
TX, TY, TZ	Point position.
NX, NY, NZ	Point normal directions.
MAPU, MAPV, MAPW	Point or vertex texture coordinates.
CR, CG, CB	Diffuse point or vertex color.
CA	Point or vertex alpha value.
CREASE	Point or vertex crease weight value.
PT2, NPT2, etc	Append 2 for the second source.

Usages in other examples

Example name	Example for
CreaseBasic	Crease surface node	Load \| Launch