Use a standard shader for simple materials. If you are looking how to modify the standard shader to achieve a plastic-y effect, consult the documentation on material effects.

For more specific effects, you may need to make your own shaders.

Use a standard shader for simple materials. If you are looking how to modify the standard shader to achieve a plastic-y effect, consult the documentation on material effects.

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There are also hints on how to make realistic materials in these charts. In essence it is about choosing a workflow (default or metallic) and obtaining relevant values for your maps or colour pickers. For instance, if we wanted to make shiny white plastic, we would want a white Albedo. Since it is not a metal we would want a dark Specular (or a very low Metallic value) and finally a very high Smoothness.

For more specific effects, you may need to make your own shaders.