# Materials

### From K-3D

In K-3D, the surface appearance of geometry is controlled by a *Material* node. There are several types of material nodes in K-3D, for each of the different Render Models, including OpenGLMaterial, RenderManMaterial, and YafrayMaterial.

Each geometric primitive in K-3D has a single material node assigned to it. Geometric primitives include:

- Conics (Cone, Cylinder, Disk, Hyperboloid, Paraboloid, Sphere, Torus)
- Points
- Polygons
- Curves (Linear, Cubic, and NURBS)
- Patches (Bilinear, Bicubic, and NURBS)
- Blobbies

To make it easy to render the same scene using different render engines, the special MultiMaterial node can link to any or all of the other material node types.