WireD tutorial

WireD tutorial

Written by Reinhard Claus 11/26/2005

This tutorial will show you how to use the WireD shader to create an image like this:

First, create a simple geometry

Cut a few additional edges into the existing faces.

Mark edges hard that you want included in the distance evaluation.

Select "Get->Property->MR Geoinformation", and make sure "transfer hard edges only" is checked. This will transfer to mental ray only the edges that you marked hard previously, and the edges that are hard by the discontinuity setting (*). Leave the other setting unchecked - this is reserved for other plugins that work in combination with the MR Geoinformation operator.

Create the following render tree. Note, the "Gradient" Node is the Nodes->Mixers->Gradient node, not the one from the Textures menu

For the gradient, use something like the following.

Check the Normalize checkbox in the WireD shader properties, and tweak the maximum width value (watching the render region) until the gradient spreads nicely over the model. Note that the WireD output usually is in scene units. Having Normalize checked changes that, the distance values are being clamped into the [0..1] range, with "1" being the maximum width value. This is pretty useful here since the Gradient Mixer Node expects an input inside the [0..1] range.

back to the instructions

(*) Note that sometimes when the edges are inside a 100% planar polygon, they're considered soft by the algorithm even though they were marked hard. Move some of the points by a tiny amount if that's the case.