fullseye

normal_map_shade — GFX2D light op

使い方

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.

参考(サンプルデータ・文献)

実行できる例(この op を実際に呼ぶ検証済みサンプル)

型が繋がる次の op(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

同カテゴリ(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.