Material Instances

A Material Instance is a variation of a Material that changes only its parameters, the values you exposed in the graph. It is the cheapest way to make variants, and what you should reach for most of the time.

Why instances are cheap

An instance does not compile its own shader. It points at a parent Material and reuses that material’s compiled shader exactly. At render time, the engine groups draws by the base material, so an instance draws in the same bucket as its parent and every sibling instance. All it carries of its own is a single row of parameter values.

So a red, a green, and a blue instance of one “Painted Metal” material are one shader, one bucket, three parameter rows, not three materials.

Creating an instance

1. In the Content Browser, right-click a Material and create an instance from it. The instance is bound to that Material as its parent.
2. Open the instance. It lists every parameter the parent exposes.
3. Tick a parameter to override it, then set your value. Parameters you leave unticked fall through to the parent’s value.

Assign the instance to a mesh slot or a Material Override exactly like a material, both accept a Material or a Material Instance.

When to use a Material instead

Make a new Material only when a variation needs something the parent’s graph cannot express through parameters, a different set of connected nodes, a different blend mode, or a different shading model. Everything else should be an instance. See Best Practices.