入画 · WITHIN
Explore 18 painting and landscape worlds through chapter tours, free roaming and walking, with driving in Roadster and boat rides in Sakura Valley.
An interactive particle-art sandbox: morph 48,000 light points between a flower, a gravity ring, and a galaxy, disturb the sculpture, and export a moment as a poster.

Details
The work description and facts above come from the upstream README. Any Astra Games guides are listed separately, with their own sources and verification notes.
Platform
Modern browser with WebGL; click the title to try it online. Free, no login or API key; the standalone HTML also works offline. Optional ambient sound requires Web Audio.
GPT-6 Astra
Creation record and model contribution — The creator used GPT-6 Astra ultra for the concept, code, and copy, with collaborative review; not a one-shot test.
Resources
Source and setup instructions · Standalone HTML · Prompt · Built with: native WebGL, Web Audio, and Canvas 2D.
Beyond the preview
Understand the controls, mechanics and use cases. Each guide states its sources and what was actually checked.
A practical way to compare a scored game, a creative sandbox and an AI development example before you open a demo.
Read guideUse form, viewpoint, motion and pause as separate creative controls in this particle-art sandbox.
Read guideExplore 18 painting and landscape worlds through chapter tours, free roaming and walking, with driving in Roadster and boat rides in Sakura Valley.
Six browser games in one arcade, including mountain rally, snowboarding and antigravity racing; counted as one collection.
An unofficial multiplayer Chao Garden fan game: choose a Sonic character, explore the garden and interact with Chao.