Adaptive subdiv + normal map renders black
Closed, DuplicatePublic

Description

System Information
Win 10, GF 780

Blender Version
Broken: 2.78 RC1
Worked: never

Short description of error
Objects using both a normal map and adaptive subdivision render as black.

Exact steps for others to reproduce the error

  1. Open attached .blend file
  2. Shift-Z

Details

Type
To Do
Brecht Van Lommel (brecht) triaged this task as "Normal" priority.Sep 4 2016, 12:22 PM
Brecht Van Lommel (brecht) changed Type from Bug to To Do.

This is a known limitation at the moment, marking as a To Do.

Hope to fix this soon, but I'm a bit curious why you need normal mapping in this file, doesn't displacement method "both" produce the correct result?

In this particular file, sure, "both" works.

Being able to use a separate normal map is important if you want to render game/realtime assets however. These are typically authored with separate normal and displacement maps and use straight tesselation instead of Catmull-Clark.

It's important that tesselation and displacement doesn't affect the normals when a normal map is used. A tangent space normal map should be applied against the basemesh normals, not the normals of a displaced mesh.