The W Coordinate texture can access the OctaneRender® W Coordinate System, which can place Gradients on hair geometry. The hair geometry stores an inherent Hair Gradient Interpolation along with hair data exported from 3D modeling applications. W is an attribute of the Mesh node, which defines a coordinate for every hair vertex per strand. This attribute is loaded from an AlembicAn open format used to bake animated scenes for easy transfer between digital content creation tools. file input. However, if the attribute is not in the Alembic file, OctaneRender® creates the coordinates per strand.
Figure 1: Hair strands rendered using the W Coordinate to distribute color