Materials

Create materials and material instances, set parameters and edit material graphs as readable text.

What it’s for

This area covers three things you do with materials: create and edit material assets, change the parameters on a material instance, and read or write a whole material graph as readable text. Your assistant uses it to set up a look, dial in a variant, or understand what an existing material does.

Material instances are the common case. An instance inherits from a parent material and overrides named parameters, such as roughness, a tint color, a texture slot or a static switch. Your assistant creates the instance from a parent and sets the overrides one at a time or all at once. It can also read an instance back and tell you what it overrides.

Your assistant can also turn a material or material function into readable text, edit that text, and build the asset back from it. That means it can work out what a material actually does and change it without clicking through node panels, and you can review the change as text.

It can also make individual node edits when you need a specific node. To move, rename or fix references to a material asset, see Assets and content.

Things you can ask

Make a tinted material instance

You get a new instance of a parent material with one parameter changed.

You: Make a red-tinted instance of M_Metal with roughness 0.2.

Created MI_Metal_Red from M_Metal in /Game/Materials, with Roughness set to 0.2.

Change several parameters at once

Roughness, tint and texture change together in one recompile.

You: On MI_Metal_Red set the tint to red, roughness to 0.2, and swap in T_Scratches.

MI_Metal_Red now has a red BaseColor, Roughness 0.2 and T_Scratches as its Detail texture.

Show a material graph as text

You get the material’s node graph as readable text, so you can see what it does before editing.

You: Show me the node graph of M_Metal as text.

Here is M_Metal as text, including the material functions it uses. It shows how BaseColor and Roughness
are built.