Confused about normals on a conical shape

PeterBroof

Hey guys, I'm working on this piece, still WIP of course, so please disregard the seam and poor material definition.

I like to do things by the book, so I like the normals on the left side - perpendicular to the surface, how it's probably supposed to be.

But there's an obvious lighting difference between the conical shape and the tip. The normals on the right though - I moved them to point like cylinder normals would and the lighting is so much better now. It's more shiny and there's less discontinuation between meshes.

I could just leave it like in the right picture and call it a day, but I'm having hard time understanding how proper normal direction just gives you this bad effect. What am I missing here?

Eric Chadwick

The change on the left model is the correct lighting. A conical surface will naturally reflect in a different direction than a cylindrical shape.

If you want a sheen more like the model on the right, then use anisotropy in your game shader, to mimic the micro parallel grooves you see in brushed metal, which create an elongated specular (elongation runs perpendicular to the groove direction).

PeterBroof

Thanks Eric! That makes sense