light_mask — GFX2D light op

• Data kinds: rgb × rgb → rgb

• Call: import gfx2d; gfx2d.light_mask(base, light, ambient=0.0) (or opsgfx2d.get("light_mask"))

Usage

Modulate an `rgb image by an rgb light map: base * (ambient + light)`.

`ambient is the light that reaches everything; ambient=1` with a black

light map returns the base exactly, which is the identity the test suite

pins.

The product is clipped to `[0, 1]`; the clipped amount is not returned.

Both arguments should be in the same encoding — mixing an sRGB base with a

linear light map is the second silent-error trap of this family, and the

only defence is that both arguments are named.

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.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• gfx2d_scene — py -3.11 examples/gfx2d_scene.py

Ops the type connects to (they accept rgb as input)

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

Same category (light)

radial_light · normal_map_decode · normal_map_shade · shadow_cast_2d

*Provenance: gfx2d.py — GFX2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

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