Table Of Contents
Introduction
Instances are lightweight copies of an object that do not contain any geometry data, but rather maintain a link to the original object. Because each instance only stores a limited amount of data – such as a transform matrix and sometimes material assignment information – they have several advantages over regular copies:
- Instances use much less disk space for scene files.
- Edits to the original are automatically applied to all of its instances, making editing many identical objects much simpler.
- Instances use very little memory when rendering using Redshift and can significantly improve performance.
A scene with 1300 instances of a high resolution Buddha model (approximately 880,000 triangles per instance). Over a billion instanced triangles.
Working with instances varies by DCC and the following sections highlight some of these differences. For a more complete guide to using instances in Maya, 3ds Max or Softimage, please refer to the respective user documentation.
Limitations
Redshift does not currently support instancing of lights or volume containers. If such objects are instanced in your scene, only the first instance will contribute to the rendering with Redshift.
How To Use
In Maya, a mesh is instanced when the mesh shape node appears multiple times in the DAG. You can create instances of an existing mesh using the Duplicate or Duplicate Special commands. In addition to storing a unique transform (position, rotation and scale) and unique visibility options per instance, Maya allows each instance of a mesh to have unique material assignments. This is a very powerful feature in that it allows for some visual variety between instances that can be difficult to achieve if all instances must share identical material assignments. Redshift fully supports instanced meshes in Maya including per-instance material assignments.