Octane for Houdini

The W Coordinate node is a way to access the OctaneRender® W Coordinate system, which provides the means to place gradients on hair geometry. It stores an inherent hair gradient interpolation along with hair data exported from common 3D modelling applications. It takes into account the basis of the interpolation set in an Octane Obj Params tab attached to a scene object (Figure 1). When you plug the W Coordinate into a Gradient texture as the Input texture, it tells OctaneRender to render the inputs as a gradient mapping based on either the hair length or the segment count per strand.

Figure 1: The Fur tab in an Octane Obj Parms tab

Figure 2: A Houdini hair system rendering using the W Coordinate to distribute colors across the hair stand length 

Figure 3: The Gradient node parameters and the node network associated with the rendering from Figure 2