eye.shader

An eye: an iris refracting behind a clear cornea.

The iris sample is displaced by refracting the view ray at the cornea and walking it iris_depth inward, so the iris slides as the viewing angle changes. The cornea itself is the engine's clearcoat lobe, which keeps one continuous specular highlight across the iris and the sclera.

iris_radius, pupil_radius and limbus_softness shape the disc; iris_texture is sampled in the refracted frame, sclera_texture in the surface's own UVs.