OSL Support Status

Supported

• Diffuse, translucent, reflection, refraction and microfacet standard closures
• oren_nayar, ashikhmin_shirley and disney principled brdf appleseed specific closures
• Emission
• Texture lookups
• Transparency
• Object coordinate systems (when not using hierarchical instancing)
• get_attribute and trace calls

Missing

• dtime and dPdtime (work in progress)
• Camera, NDC and screen coordinate transforms
• Bump mapping (requires ray differentials)
• Background closure, is ignored right now. It shouldn't be too difficult to add
• Holdout and debug closure are ignored (we need some refactors to support it)
• Add OSL scenes to unit tests

Not yet supported by appleseed

• ShaderGlobal members that depend on ray differentials are set to 0 (we don't have ray differentials in appleseed yet)
• Geometry user data
• Displacement
• Subsurface scattering
• Arbitrary AOVs from shadergroups

Would be nice to have

• Light attenuation shaders
• Named coordinate systems
• More closures

Should work but untested

• Point clouds (using partio)
• Texture3d (using Field3D)