Cannot apply Normal Map to Sprite3D
Created by: grotar00
Godot version: 3.0.2 3.0.6
OS/device including version: Windows 10 Pro 64 bit
Issue description: I have a Sprite3D object with SpatialMaterial applied in GeometryInstance tab. Everything looks good until a normal map is enabled: sprite gets darker and stops reacting to any light sources regardless of normal texture picked (or none): However, material is rendered as intended on the preview ball: Also same material works fine with plane MeshInstance.
Steps to reproduce: Bumped into issue on Godot v3.0.2 (noticed fps drop when sprite entered viewport first time) and reproduced on v3.0.6 by creating a new project with initial settings, adding Sprite3D, adding SpatialMaterial to it and enabling normal map.
Minimal reproduction project: Sprite3D Normal Map.zip