i am a complete newbie when it comes to Unreal Engine, but i am a 3D artist with very rich experience in physically based rendering. I am recently starting to explore game engines to review their capability when it comes to photorealistic rendering, and try to push them to their limits.
From rendering engines, i am used to a scheme where there is some base material with some parameters, into which i can then plug textures and various nodes to create shading network. Unreal engine works on very similar scheme, but i failed to find some basic material properties in the base material node. For example, if i unplug all nodes from the physical material node, i get black, but specular material. So my questions are:
Are there any parameters to control appearance of the material in the base node itself? And if so, where can i find them?
OR do i need to always drive all basic material parameters by nodes, like diffuse or specular color?
Which parameter defines that material is specular if there is not any node connected to it? Why is it specular by default?
And i really dislike working with roughness, since it’s just counter-intuitive form of glossiness parameter, so i was looking for some invert node, that would allow me to invert my glossiness shading network to convert it to roughness, but i did not find any. Is there any node that can invert RGB map result?