Hi,
what should be the setting of material and light to render a tube geometry to appear like a metallic tube?
I’ve already search for it on other discussion into the forum and on the samples program but I was not able to find it out.
Thank you in advance.
Metal is hard to do right. If you are using Phong or something close to it, then you need a high gloss value and a texture that looks like metal. It will look much better with any kind of reflections, even a cheese spheremap will help, cubemap is a better option (just a static sky box) and screen space reflections will do wonders.
If you are after something more realistic - there’s Tobias Render Pipeline for PBR, there you just have to set how metallic you want your object to be.
The thing about metals is that they have no diffuse reflection at all but only a specular reflection. To get good results with this you need some sort of environment map since just using the specular highlight won’t generate good results. In the simplest case, these are usually pregenerated from a particular viewpoint in the scene. This technique is explained in the manual.
To make a metal rough instead of perfectly shiny, you can blur the resulting environment map, or add a bias to the sampled mipmap level.
Actually, in order to render realistic metals, you need an anisotropic BRDF. This basically works by using two BRDFs over the u and v derivatives, and is used for achieving the typical metallic look:
http://www.cs.ubc.ca/nest/imager/tr/2011/DisplacementInterpolation/BRDFA.jpg
However, I do agree on the others that you can get good results by just using an environment map and a pure specular component