Rendering attributes

RIB attributes

Name Type Description
interpolateboundary Detail, Primitive

This attribute will turn on the interpolate boundary flag for sub-division surfaces in the RIB stream and can be set to 1 or 0.

ri_curvestep Detail

Determines the step value for curve primitives.

ri_curvebasis Detail

Determines the basis used for cubic curve primitives.

ri_curveinterpolation Detail

Determines the interpolation (linear or cubic) for curve primitives.

ri_subdivscheme Detail

Determines the subdivision scheme to be used. Defaults to catmull-clark.

creaseweight Primitive, Vertex

Defines the crease weight for sub-division surfaces.

Pref Matrix primitive attribute for metaballs.

Determines the rest position for metaballs.

Mantra attributes

Name Description
orient

Determines orientation of curve/point primitives. Curves and points will be oriented so that their normals point in the direction of the “orient” vector attribute.

v

Used for velocity motion blur computations.

uv

Default attribute for the -u option (may be overridden by command line option).

vm_photon

vm_surface

vm_displace

shop_vm_photon

shop_vm_surface

shop_vm_displace

Shader overrides (per primitive).

width

pscale

Used to determine width of curve/point primitives (see below).

Note

The scale attribute is not used by mantra.

When determining the size of point primitives, the following checks are done (in order):

  1. Point attribute width

  2. Point attribute pscale

  3. Detail attribute width

  4. Detail attribute pscale

When determining the width of curve primitives, the following checks are done (in order):

  1. Vertex attribute width

  2. Point attribute width

  3. Primitive attribute width

  4. Detail attribute width

  5. Point attribute pscale

The first attribute found will determine the size of the point/curve primitives.