Fur Component

Owned by Mircea Barbulescu-Sosoiu
Mar 08, 2023
3 min read

Overview

The Fur component renders the model in layers, creating the effect of a furry surface; it can be attained for short-hair fur effects only.

The component makes use of the normals and vertex color geometry info to compute a general fur direction, where the Red and Green channels give the direction in the Tangent and Binormal space.

Furthermore, a surface can have areas without any fur or with shorter fur. This aspect can be controlled using a fur texture mask.

The quality of the fur rendering also depends on the values of fur length, the number of fur layers, and a global fur direction multiplier.

Note!

Fur rendering is expensive resource-wise as, in theory, the model is rendered several times (number of fur layers) per frame to create the effect. Performance-wise, lowering the mesh fur layers helps, although it causes a drop in quality.

Asset Requirements

  • geometry exported with Normals info

  • geometry exported with Vertex Color info

    • Red and Green Channel represents a direction in Tangent and Binormal plane.

    • Alpha Chanel is a fur length factor

  • diffuse texture – RGBA texture

  • Fur Mask

    • Red channel controls the mix between normal specular and aniso specular

      • 0 is normal

      • 255 is specular

    • Green channel is an additional layer alpha control. Alpha is the length, all lower value pixels are discarded, everything above will render at a calculated opacity, the green channel adds an additional transparency control.

    • Blue channel is the fur aniso specular intensity

    • Alpha Channel is used as fur length, controlling a smoother blend between fur areas (values closer to 255) and furless areas (values closer to 0) of the rendered surface.

Material options*

* Material Options can only be modified from the Animaze Editor.

  • Fur Direction Multiplier - helps you with emphasizing or downplaying the Fur Direction in your Animaze fur materials.

    • The fur direction is read from vertex color info, to compute a general fur direction. It is being expressed in Tangent Space. The Red and Green vertex color channel values are used to perceptually “bend” the fur on the Tangent and Binormal axis respectively.

    • You can change the fur direction by changing the values in the red and green channels in the vertices’ color component, and then you can amplify or downplay this established direction via the numeric value of the fur direction multiplier (it can also be negative to go in the opposite way).

  • Fur Length - value expressed in model space scale, controls the maximum fur length. Smaller values (0.01 for a 0.7m avatar) will make the surface seem opaque, while going for larger values (1 for a 0.7m avatar, which means the fur length is 1 meter), will make the fur layers visible and debunks the fur effect.

  • Fur Specular Gloss - fur specular gloss value

  • Fur Opacity - controls a self-shadow component of the fur, the higher the value the darker the roots become.

  • Mesh Layers - number of mesh layers determines the fuzziness of the fur rendering, a high number will make the surface seem very dense, while a low number will make the avatar look like it extrudes layers.

  • Fur Mask

  • Fur Mask Mipmap Bias - a way to control the texture mipmap, the default value will make the fur details (e.g. clumps) will lose the effect at reasonable camera-to-surface distances, using this option you can offset the effect much further when fur details are insignificant anyway.