Open-source projection mapping you can actually fork
The open-source projection mappers most people know are copyleft desktop apps with uneven cadence: MapMap (GPLv3) still gets commits but hasn't tagged a release since 2018, Splash (GPLv3) ships slowly (0.10.8 landed in 2024), and VPT is source-available and effectively frozen at its 2018 release. Projektor is a fresh, actively-developed, MIT-licensed codebase — and it runs in the browser instead of a per-OS binary.
MIT means you can read it, fork it, embed it, and build on it commercially without the GPL's copyleft strings — a real difference from MapMap/Splash and from the closed browser mappers (map.club, 4mapper). The render engine is deliberately framework-agnostic (it consumes a plain scene snapshot per frame), the whole thing is TypeScript + raw WebGL2, and it ships an MCP server so an AI agent can drive the editor.
A modern, actively-developed, MIT-licensed projection mapper — permissive where the GPL desktop tools aren't, in the browser, with a live shader editor and agent control.
Side by side
| Projektor | MapMap | VPT | Splash | |
|---|---|---|---|---|
| License | MIT | GPLv3 | Source-available | GPLv3 |
| Release cadence | Active | Commits; no release since 2018 | Frozen (2018) | Slow (0.10.8, 2024) |
| Runs in a browser | ||||
| Cross-platform | Any browser | Linux-first | Win/Mac | Linux-first |
| No paid runtime dependency | Needs paid Max | |||
| Live GLSL shader editor | Via Max | Some | ||
| AI-agent controllable (MCP) | ||||
| Share project as a URL |
MapMap and Splash are GPLv3; VPT is source-available freeware that requires a paid Max runtime to modify. MapMap's last tagged release was 0.6.2 (2018) though its repo still sees commits; Splash shipped 0.10.8 in 2024; VPT's last release was 2018.
Where the other tools still have an edge
- Splash targets calibrated multi-projector dome/immersive rigs with camera-based blending — a specialist niche Projektor doesn't cover.
- Native desktop apps can tap OS-level video I/O (Syphon/NDI/Spout) the browser sandbox blocks, and run offline with no page load.
- "Open source" isn't unique — MapMap and Splash are GPLv3; Projektor's edge is the permissive MIT license, active development, browser delivery, and agent control, not merely being open.
FAQ
Is there an actively-maintained open-source projection mapper?
Yes — Projektor is MIT-licensed and under active development. Among the classic tools, Splash (GPLv3) still ships releases (0.10.8 in 2024) and MapMap (GPLv3) gets commits but hasn't tagged a release since 2018; VPT has been frozen since 2018.
Why MIT instead of GPL?
MIT lets you fork, embed, and build commercial work on top without copyleft obligations. MapMap and Splash are GPLv3, so a permissive license is a genuine differentiator for a tool people want to embed in installations and other apps.
Is Projektor the only open-source browser mapper?
It's the most capable and actively-developed MIT-licensed browser mapper we know of. Small OSS browser experiments exist, and the free browser tools map.club and 4mapper are closed-source — so Projektor's claim is permissive-license + active development + depth, not "the only one."
Where's the source and how do I contribute?
The code is on GitHub with a CONTRIBUTING guide covering the engine boundary and how to add a media source. Issues and PRs are welcome — start from the README.