Answer by NicolasLIATTI

Hi, You should try this: if (GUI.Button(new Rect(10,10,60,20), "256x256")) { ProceduralMaterial substance = renderer.sharedMaterial as ProceduralMaterial; if (substance) { substance.SetProceduralVector("$outputsize", new Vector4(8.0f, 8.0f, 0.0f, 0.0f)); substance.RebuildTextures(); } }