Cel shading: tuning pass (glossy highlights / env reflection, bands, shadows, outlines) #726

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opened 2026-10-12 17:42:36 +00:00 by sky_line · 0 comments

sky_line commented

2026-10-12 17:42:36 +00:00

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Cel shading (#550) works, but it has had little real-world tuning. Do a look pass over it in varied scenes and lighting, and tune what needs it.

Things to check

Shiny / glossy surfaces: the environment reflection on the cel path isn't attenuated, and the cel specular step can read as a solid bright patch on flat glossy faces instead of a highlight. Possibly scale the cel env reflection and specular (named constants in clean_cel_common.glsl, celSpecStep).
Band count and thresholds of the toon light ramp under bright sun, sunset, night and indoor local lights.
Shadow tint / strength in the cel shadow band, with sun shadow maps and RT shadows.
Outline width and colour (clean_cel_outline.frag) at different distances and render scales (FSR / upscaling), and on avatars vs. objects.
Emissive, fullbright and glow with cel on.
PBR vs. legacy materials: both should read consistently.
Avatars vs. world: the avatar mask (Cel P6).

Deliverable: tuned defaults, with any user-facing knobs that turn out to matter exposed in the cel settings. Use before/after screenshots in a few reference scenes.

Cel shading (#550) works, but it has had little real-world tuning. Do a look pass over it in varied scenes and lighting, and tune what needs it. **Things to check** - **Shiny / glossy surfaces:** the environment reflection on the cel path isn't attenuated, and the cel specular step can read as a solid bright patch on flat glossy faces instead of a highlight. Possibly scale the cel env reflection and specular (named constants in `clean_cel_common.glsl`, `celSpecStep`). - **Band count and thresholds** of the toon light ramp under bright sun, sunset, night and indoor local lights. - **Shadow tint / strength** in the cel shadow band, with sun shadow maps and RT shadows. - **Outline width and colour** (`clean_cel_outline.frag`) at different distances and render scales (FSR / upscaling), and on avatars vs. objects. - **Emissive, fullbright and glow** with cel on. - **PBR vs. legacy materials:** both should read consistently. - **Avatars vs. world:** the avatar mask (Cel P6). **Deliverable:** tuned defaults, with any user-facing knobs that turn out to matter exposed in the cel settings. Use before/after screenshots in a few reference scenes.

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2026-10-12 17:42:36 +00:00

sky_line added this to the Slipstream project

2026-10-12 17:42:37 +00:00

sky_line referenced this issue from a commit

2026-10-12 20:07:06 +00:00

#726: cel rim lights silhouettes, not ground seen at a grazing angle