normal_map_shade — GFX2D light op

数据种类:normalmaprgb

调用: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

用一盏平行光给 2-D 法线贴图着色(Lambert + Blinn 1977)。

> 以下的详细说明为原文 —— 摘要与标题已翻译。

`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(示例数据・文献)

• 示例数据目录(下载 URL / 许可证) —— 2-D 用 skimage.data(BSD/公有领域)加合成图,3-D 给出真实数据源(Stanford/PDS 等)的下载 URL。

• 算子来历与参考文献 —— 该算子族所依据的研究/方法出处。

• 算法的正典(作者・年份)与用途见上面的族使用指南

可运行的示例(实际调用该算子并已验证的样例)

gfx2d_scenepy -3.11 examples/gfx2d_scene.py

类型可衔接的下一个算子(可接受 rgb 作为输入)

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

同类别(light)

radial_light · light_mask · normal_map_decode · shadow_cast_2d


*Provenance: gfx2d.py — GFX2D 算子登记表。本条目由 tools/opdocs.py md 自动生成(请勿手工编辑)。*

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