Orientation of the tangent-space normal map's green (V) axis.
OPENGL (the engine's default): green points up (+Y). This is the Web/glTF convention and
matches the shader's tangent-space read path (N = v_tbn * (rgb*2-1)) with the flat
normal pointing toward the viewer. Never mix handedness between the authoring tool and the renderer,
or bumps render as dents.
Type Declaration
ReadonlyDIRECTX: "directx"
Green down (-Y). Required by some desktop DCC tools and legacy engines.
ReadonlyOPENGL: "opengl"
Green up (+Y). Web/glTF default; the Small World engine's convention.
Orientation of the tangent-space normal map's green (V) axis.
OPENGL (the engine's default): green points up (+Y). This is the Web/glTF convention and matches the shader's tangent-space read path (N = v_tbn * (rgb*2-1)) with the flat normal pointing toward the viewer. Never mix handedness between the authoring tool and the renderer, or bumps render as dents.