normal_map_shade — GFX2D light op

資料種類:normalmaprgb

呼叫: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')(或 opsgfx2d.get("normal_map_shade"))

用法

用一盞平行光給 2-D 法線貼圖著色(Lambert + Blinn 1977)。

> 以下的詳細說明為原文 —— 摘要與標題已翻譯。

`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.

參考(範例資料・文獻)

• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。

• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。

• 演算法的正典(作者・年份)與用途見上面的族使用指南

可執行的範例(實際呼叫該運算子並已驗證的樣例)

gfx2d_scenepy -3.11 examples/gfx2d_scene.py

型別可銜接的下一個運算子(可接受 rgb 作為輸入)

srgb_to_linear · linear_to_srgb · blend_mode · light_mask · normal_map_decode · bloom · vignette · chromatic_aberration

同類別(light)

radial_light · light_mask · normal_map_decode · shadow_cast_2d


*Provenance: gfx2d.py — GFX2D 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.