Basic fur setup

1. Click the Grid tool on the shelf, then click in the scene view to place a new surface.

2. Double-click the name of the object node and rename it Fur.

3. Press 4 to enter component mode. This moves you down into the geometry inside the object you just created.

4. Press Tab in the viewer and type fur to create a Fur surface node in your geometry object and connect the grid to its first input.

   The Fur SOP has three inputs.

   1. Skin geometry – the surface on which to create the fur (the grid in this example).

   2. Guide geometry – curves representing guide hairs. See using guide hairs for more information.

   3. Clump geometry – See clumping.

5. The Fur node and the procedural shader pick up attributes from the skin geometry and apply them to the hairs. By default, they will grab all attributes on the surface (the Skin Attributes parameter is *), but only some are meaningful to the fur nodes (for example, width, Cd, furdensity). See the node documentation for a complete list of attributes.

   The default width of hairs is quite thick, so we’ll add a width attribute to the surface, which will be copied onto the hairs and set it to a lower value.

   Insert an AttribCreate node between the Grid and Fur SOPs and change the Name parameter to width.

6. Set the first Value field to 0.025. (Make sure to set the Value, not the Default.)

Since we will render using the procedural shader, we're using the fur surface node for visualization only, so we need to prevent it from rendering.

1. Create a Null node in your geometry object and Ctrl-click its display flag to set the render flag on it. Do not connect the Null to any other node.

   The render flag controls which node is rendered. By putting it on a disconnected null, we ensure the geometry in this object will not render.

2. The fur procedural shader needs an object containing the skin geometry (because the renderer only knows about objects). So we’ll extract the skin geometry out into a new object and then reference it in the fur procedural shader.

   Create another Null node in your geometry object between the AttribCreate node and the Fur SOP and name it SKIN_OUT.

   We’ll use this Null as the target for extracting the geometry. The Null should always be the node connected to the Fur node’s skin geometry input. This lets us insert nodes above the Null later.

3. Select the SKIN_OUT node in the network editor, and select the grid in the viewport, then click Extract on the Modify shelf tab.

   This will create a new geometry object that automatically references SKIN_OUT.

4. Click obj in the path at the top of the network editor to return to the object level, and rename your new geometry object SKIN_REFERENCE.

5. Select the SKIN_REFERENCE node. In the parameter editor, click the Render tab and turn off Renderable to prevent double rendering. Also, turn off Automatically Compute Normals on the Geometry subtab of the Render tab.

6. Double-click the Fur node to go into its geometry network, and use the Tab key to create a SHOP Network.

   

7. Double-click the SHOP network to dive into it. Press Tab and type Mantra: Fur Procedural to create a Fur Procedural node.

8. In the parameter editor of the fur procedural shader, click the node chooser button next to Skin and choose your SKIN_REFERENCE object from the tree.

9. Click obj in the path at the top of the network editor to return to the object level. Select the Fur object. In the parameter editor, click the Render tab, then click the Geometry sub-tab. Click the node chooser button next to Procedural Shader and choose your fur procedural from the tree.

The hair material is a basic material for use with curves, which gives the geometry a fur or hair look. This material uses a special normal with the diffuse and specular to give a tubular look to non-dimensional curves.

1. Click the Material Palette tab above the network editor. Drag and drop a Hair Material (under Organic) from the list on the left side onto your grid object.

2. Set up lights and do a test render.

   

It is not necessary to apply the hair material; however, it will give your fur a more natural look and allows you to set the color. You can also set the color using the Changing the color of the fur using the color attribute or the Control the Fur Color using a Color Map tutorials.

• The fur procedural shader parameters are very similar to those of the fur SOP and can be referenced so that when you make changes to them they will be automatically updated in the viewport. For example, if you change the length or density you might want it to be reflected in the viewport without having to change it in both nodes.

  To reference parameters, right-click the parameter name and select Copy Parameter, then right-click the matching parameter name on the fur SOP and select Paste Copied Relative References.

• You can turn off the Renderable checkbox on the Render tab of the SKIN object if you don’t want the grid surface in the render.