GitHub - blackears/blenderNormalBrush: Blender addon that allows you to adjust normals with a brush stroke
Is it possible to select normals in Blender based on the direction they are facing, so they can be flipped? - Quora
![Recalculating and flipping normals not working—but manually re-adding the faces does? (Simple mesh) - Blender Stack Exchange Recalculating and flipping normals not working—but manually re-adding the faces does? (Simple mesh) - Blender Stack Exchange](https://i.stack.imgur.com/JzDpS.jpg)
Recalculating and flipping normals not working—but manually re-adding the faces does? (Simple mesh) - Blender Stack Exchange
![What is the exact correct normal map interpretation for Blender? - Graphics and GPU Programming - GameDev.net What is the exact correct normal map interpretation for Blender? - Graphics and GPU Programming - GameDev.net](http://i.imgur.com/4O61kwB.png)