Menu

Individual skill

3d-sky-rays

0upvotes

Add sun shafts and crepuscular rays to a Three.js or equivalent 3D scene, using scene occlusion, a projected sun position, controlled foreground spill, and scalable post-processing. Use for rays of light from the sky, sunlight through trees or roofs, and golden-hour architectural scenes.

agent-skills/3d/3d-sky-rays/SKILL.md

Read pinned source

Source commit 5ea1661a0e05d82b054553daaa6baf6d0233c33c

What was checked

Matches the observed repository HEAD
Yes
Scanner rules are current
No
Repository scan complete
No
Skill scan complete
No
Observed behavior
Not checked yet
Last checked
Nov 8, 2026

These are observations at the recorded commit, not a guarantee of safety. Review the source before running it.

Install this skill

Choose an agent in your Stack or copy a command below. Commands fetch the pinned commit and copy only this skill directory. Existing destinations are refused. Copying a command does not install anything.

An install command is unavailable: current rules, complete repository and skill scans, an eligible behavior level and a permitted license are required.

Repository context

Repository stars (not skill ratings)
7,324
Repository last updated
Nov 5, 2026
License
MIT

Observed agent integration: No specific integration evidence. Standard SKILL.md installation does not imply verified compatibility.

Files and excerpt

File metadata and permitted, redacted excerpts come from the recorded scan. Source links are pinned to that commit.

Browse files
Read excerpt

# 3D Sky Rays

Make the light appear to travel through gaps in the scene. Roof edges and foliage should shape the shafts as the camera moves.

## Fit the existing renderer

Inspect the renderer version, render targets, alpha usage, depth path, tone mapping, and post-processing order. Keep the existing WebGL or WebGPU backend. The shader recipe below describes a WebGL screen-space effect; implement the equivalent in the project's node/render pipeline when using WebGPU.

Use one normalized world-space direction pointing **toward the sun** for the sky, ray source, and directional lighting. If the art direction deliberately offsets the visible sun from the lighting sun, document and control that offset in one place.

## Build an occlusion-aware ray pass

1. Render scene color in linear HDR. Obtain a mask identifying open sky: white for sky, black for opaque occluders. Match foliage alpha cutouts and vertex motion in the mask pass so leaves do not become solid rectangles.
2. A dedicated sky mask is the portable default. Reusing scene alpha is an optimization only when every preceding pass preserves its meaning: sky alpha 0, opaque geometry alpha 1. Transparent glass, particles, canvas compositing, and AO can break that convention; inspect the mask directly.