Autodesk 12812-051462-9011 User Guide 3 - Page 1335

Hair Rendering Options group Hairs Sets the method to be used for rendering hair: ■ buffer (The default) Procedural hair generated by Hair at render time based on the modifier parameters. Buffer hair is generated by a special renderer within Hair and offers the benefit of being able to create millions of hairs with minimal memory requirements. Only one hair is in memory at a time. Also, using Buffer render offers a variety of compositing options (described below). ■ geometry Creates actual geometry for the rendered hair at render time. This geometry is assigned the material ID set by the Hair And Fur modifier > Geom Mat ID parameter on page 1168. NOTE "Geometry" hair derives its texture from the growth object, not from any maps applied via the Material Parameters rollout. Compositing options aren't available with "geometry" hair. The "geometry" option works with both the default scanline renderer and the mental ray renderer. ■ mr prim Hair is generated by a procedural mental ray shader that generates mental ray curve primitives directly into the mental ray rendering stream at render time. Choose this option only when you are rendering hair with the mental ray renderer on page 6230. mr Voxel Resolution Available only for the "geometry" and "mr prim" Hairs options. At render time, hair boundaries are subdivided into volume cubes or "voxels." 3ds Max calculates which hairs are in each voxel, and when a ray enters a voxel, it calculates for those hairs. This allows unneeded voxels to be removed from memory during calculation. With "geometry" rendering, voxels are used only for calculating instanced hairs. This value gives the resolution of the subdivision. For example, a value of 3 subdivides the volume into 3 x 3 x 3 voxels, for a total of 27. The higher this value, the more efficient calculations can be. Default=5. Lighting ■ native (The default.) Uses standard 3ds Max calculations for light falloff. ■ emulation Performs a simpler internal calculation for light falloff within the buffer render. It applies only to the buffer hair rendering itself, not the 3ds Max scene. This mode omits features such as illumination textures on 6590 | Chapter 21 Effects and Environments