Vector Displacement - Arnold for Maya
| Further Reading |
|---|
| See Displacement in the Arnold User Guide for the full shader documentation. |
Sea waves displaced using a vector map
A Maya scene file and ear vector displacement map can be downloaded here.
| More information about vector displacement shaders can be found here. |
When using Color Management in Maya (2017), vector displacement maps should be set to RAW.
Workflow
- First, you must set the Subdivision Type to Catclark and increase the Subdivision Iterations. Start off with low values and steadily increase the number until you achieve a good quality displacement effect. Subdividing the base mesh is essential. Otherwise, you will start to see faceting and normal mismatch issues when using low polygon base meshes.
Catclark subdivision with 6 subdivision_iterations
- In this case, we have exported a preset vector map from Mudbox and rendered it with Arnold. It was exported as a 32-bit EXR image to retain the highest quality for the vector displacement effect.
- The vector map must be connected to the Vector Displacement of the Displacement node. Be sure to connect the whole attribute and not component by component.
Vector Displacement map connected to Vector Displacement attribute of a Maya displacement node (Vector space set to Tangent)
Vector Displacement
Input attribute for connecting a vector displacement map.
Vector Encoding
Floating Point Absolute (for floating-point maps) or Signed Encoding (usually 8-bit maps, whose RGB is remapped to the (-1..1) range).
Vector Space
Can be World, Object, Tangent. This is the coordinate space where the vector is applied. The default is Tangent. If so, there are three ways of defining the tangent:
- Having a UV space, so that the shader can use the U derivative as the tangent direction
- Specifying a Tangent vector by hand (for instance 1,0,0 for a flat grid) or mapping it via a texture. This option is used if the Tangent vector is not null (0,0,0).
- Letting Arnold do its best to guess a tangent. The shader defaults to this option if there is no UV space and Tangent is null.
Tangent
Input attribute for connecting a tangent-based vector displacement map.
- The image is computed in tangent space, which works well in conjunction with deformed geometry (see the image below). MtoA supports all the Vector Spaces from the Maya Displacement shader (object, world, and tangent).
Vector displacement map set to tangent space assigned to deformed geometry