The Instance Range node maps a range of instance IDs (0 to Maximum ID) to greyscale values (black to white).
In Modo, this node can be used in materials for geometry which is an Instance, Instance Source or Replicator Prototype.
In this example, the Maximum ID is set to 35, to color a grid of 6x6 instances with IDs from 0 to 35.
Maximum ID - This value should correspond to the total number of instances in the scene for which the material is applied.
Invert - Inverts the texture values.
NOTE: The Particle ID of Meshes and Instances can be set per item. To do this, select a Mesh > Channel List > Particle ID, and set it to a whole number (e.g. 1, 2, 3 etc)