light op• データ種: normalmap → rgb
• 呼び出し: import gfx2d; gfx2d.normal_map_shade(normals, light_dir=(0.0, 0.0, 1.0), ambient=0.1, diffuse='reference', specular=0.0, shininess=32.0, view_dir=(0.0, 0.0, 1.0), scheme='okabe_ito') (または opsgfx2d.get("normal_map_shade"))
Shade a 2-D normal map with one directional light (Lambert + Blinn 1977).
`normals is a normalmap: (H, W, 3)` unit vectors, as
:func:normal_map_decode returns. Non-unit input raises rather than being
normalised for you — a normal map that is not normalised is usually a map
that was never decoded, and quietly fixing it hides the mistake.
`out = diffuse * (ambient + max(n·l, 0)) + specular * max(n·h, 0)^shininess`
with `h` the normalised halfway vector between light and view.
Directions are `(x, y, z)` with **+x right, +y down, +z out of the
screen** — the same handedness as the pixel grid, so a light at
`(0, -1, 1)` comes from above the screen. Getting the sign of y wrong
flips the perceived relief (bumps become dents) without raising anything;
that is the one thing to check on first render.
• サンプルデータ カタログ(DL URL / ライセンス) — 2-D は skimage.data(BSD/public)+ 合成、3-D は実データ源(Stanford/PDS 等)の DL URL。
• 演算子の来歴・参考文献 — この op 族の元になった研究/手法の出典。
• アルゴリズムの正典(著者・年)と用途は上記ファミリ使い方ガイドに記載。
• gfx2d_scene — py -3.11 examples/gfx2d_scene.py
rgb を入力に取れる)srgb_to_linear · linear_to_srgb · blend_mode · light_mask · normal_map_decode · bloom · vignette · chromatic_aberration
light)radial_light · light_mask · normal_map_decode · shadow_cast_2d
*Provenance: gfx2d.py — GFX2D operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.