MaterialInstance SetParameterValue Performance Impact

Graphics
#1

I have several instances of a material. The editor user can change the parameters of these instances via variables in actors. I make the change with something like: materialInstance.SetParameterValue(“rgba”, Prgba); setting a material parameter value (in this example the base color). Is there any appreciable overhead to changing these parameter, e.g. if I have a task ticking at 1 second intervals setting 8 parameters on 20 different instances do I need to put in some checks so I only actually SetParameterValue if a value has changed or am I OK to just blindly reset them all every second?

Edit:
I figured a more elegant way to check if they need setting, but still interested if anyone has any performance insights into changing the material instances while they are in use.

#2

This depends if you’re using C# or C++, because C# uses an additional bindings layer that converts values (esp. that material parameter value can be any object - scala, vector, texture, etc.).

If you’re looking for more optimal way you can also cache material parameters and set their values directly:

MaterialParameter param = Material->GetParameter(name); // cache parameter pointer
param.IsOverride = true; // call only once
param.Value = value;
1 Like
#3

Perfect, thanks!