Normal MapにはOpenGL形式とDirectX形式がある

Tangent SpaceのNormal Mapの話

Yの正負方向が反転している

https://gyazo.com/82a4bb32e939ec8d6a18129523722358

OpenGL

Yの+方向は上にくる

AMD

Maya

Verigo

OpenGL

Unity

Blender

DirectX

Yの+方向は下にくる

3dsMax

Substance

NVidia

UE4

@andrewpprice: Technical artists: Is there any mathematical formula that can tell whether a normal map is OpenGL or DirectX format? It's crazy that in 2025 users are still guessing.

https://gyazo.com/7e47b78a8581bcc76aa15c2a45cae64c

https://gyazo.com/f0277851b4a6fc6ed509c9e3ef792d79https://gyazo.com/8d20efc8ba88d1841edbad68d427eb7d

blenderならこの2つのどちらかで直せば良い