brdf_hapke — 3D `render` op

• Data kinds: normalmap → image2d

• Call: import render_shade; render_shade.brdf_hapke(normals, light=(0.0, 0.0, 1.0), view=(0.0, 0.0, 1.0), w: 'float' = 0.42, g: 'float' = -0.35, B0: 'float' = 0.87, h: 'float' = 0.01, roughness_deg: 'float' = 26.0) -> 'np.ndarray' (or ops3d.get("brdf_hapke"))

Usage

Shade a normal map with the Hapke reflectance law (opposition effect + multiple scattering + macroscopic roughness θ̄) and return I/F `(H, W)`.

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

Runnable examples (verified samples that actually call this op)

• itokawa_regolith_hero — py -3.11 examples_3d/itokawa_regolith_hero.py

Ops the type connects to (they accept `image2d` as input)

fuse_to_voxel · fit_poly_surface · eval_poly_surface · surface_form_error · background_flatten · polar_unwrap · fit_zernike · matcap_shade

Same category (`render`)

project_points · render_point_depth · render_volume_projection · render_shaded · ambient_occlusion · cast_shadow · phong_shade · matcap_shade

*Provenance: render_shade.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

brdf_hapke — 3D render op