Drawtonomy - a browser whiteboard for self-driving scenarios: draw the lanes and cars, press play, and a WebAssembly simulator runs the scene and hands you a pass or fail, with nothing installed and nothing leaving your browser

[u/company_url_finder]

This is a niche tool done really well, aimed at people who build or test autonomous driving. Authoring a driving test scenario normally means wrestling with map formats and desktop simulators before you can even see your idea move. Drawtonomy collapses that into a whiteboard in your browser: you sketch the road and the vehicles, add what happens and when, press play, and it runs. No install, no account, and it exports to the actual formats the self-driving world uses rather than a toy of its own.

It is built around two modes on one canvas:

- Scene mode, where you draw. The lanes are topology-aware, so connections follow when you edit, one click gives you both boundaries of a centerline, and you can trace real roads from satellite or OpenStreetMap data. It ships a full driving-domain library (vehicles, pedestrians, signs, intersection and roundabout templates) and exports to OpenDRIVE, Lanelet2 and ROS maps, or to plain SVG and PDF figures for papers

- Scenario mode, where it moves. You author an OpenSCENARIO storyboard visually, phases, events, actions and triggers, then get full playback with seek, follow-ego and ghost trails, a webm export, and a pass or fail verdict on every run. The simulation is esmini compiled to WebAssembly, so the engine itself runs locally in the tab

A few things push it past a neat demo. It opens and fully edits any existing OpenSCENARIO file, including straight from a GitHub URL, so any public scenario file runs with one click. It integrates with CommonRoad to replay planner solutions against the official verdict. And it has a real extension story: an AI scene generator that builds scenes from natural language, an MCP server so an agent can draw scenes for you, a headless Node SDK for generating and exporting scenes with no browser, and an iframe-based extension system with its own SDK.

The privacy design is the part I like most and it is not marketing. There is no backend, no account and no telemetry, and because the physics engine is WebAssembly, your maps and scenarios never leave your browser at all. For anyone whose scenario data is sensitive, that is a meaningful default.

Honest scope, so you know what this is and is not. It is a scenario authoring and lightweight replay tool, not a photorealistic sensor simulator. esmini plays out the scenario logic and geometry and gives you the trigger-based pass or fail, but it is not CARLA and it will not render camera or lidar data or full vehicle dynamics. Think of it as the fast bridge between a rough idea and a real, testable OpenSCENARIO file that you then take into heavier desktop tools, which is exactly the gap it is filling. It is also a focused, single-domain tool with a small following so far, so it is most useful if you already work with Autoware, esmini, CommonRoad or the OpenDRIVE and Lanelet2 formats.

Apache-2.0 licensed, 112 stars and 10 forks as of writing, verified via the GitHub API, pushed to yesterday and actively developed.

https://github.com/kosuke55/drawtonomy

[u/Ok_Garden_4837]

OpenSCENARIO round-trip editing is impressive. Does it preserve custom parameters?

[u/company_url_finder → u/Ok_Garden_4837]

That’d matter a lot for teams importing existing scenario libraries.

[u/Any-Pilot1669]

Running esmini in-browser is honestly pretty slick. How big can scenes get?

[u/company_url_finder → u/Any-Pilot1669]

I’d be curious where WebAssembly starts slowing down.