Let’s go step by step.
- In SpeedTree, I create my plants, trees, etc. making sure all normals are consistent.
- Import .srt into UE4. Some of the faces have been flipped!
- This causes the plants to shade incorrectly. The backsides of these flipped faces look like they’re receiving direct light.
- Multiplication of the normal map with ‘two-sided sign’ node causes both sides of a face to receive same lighting information which makes it undesirable.
So is this issue happening during SpeedTree’s export or UE4’s import?
I’ve posted this issue even in the SpeedTree forums.
I sincerely request the UE4 developers to fix this problem so that we can have great looking foliage.
Screenshots with descriptions here.
http://postimg.org/image/6tym5fi2p/