MapLineDraw lets you sketch corridors of railway lines or roads on an interactive map using smooth spline curves, ready to share with others.
Whether you're a transit enthusiast, a city planner, or just someone who loves to visualize infrastructure, MapLineDraw is a free and open source web application designed to let you draw smooth curves on a map provided by OpenStreetMap.
MapLineDraw is a free, open source web application that lets you draw smooth spline curves directly on an interactive map (using OpenStreetMap tiles). The tool is ideal for:
- Sketching railway lines, highways, race tracks, or other paths
- Measuring real-world infrastructure curves
- Visualizing concepts for future public transport
- Sharing your ideas with others using simple, link-based projects
Typically line-drawing tools rely on connected straight segments. MapLineDraw uses cubic B-splines, which means it can represent curves with continuous curvature — an important feature in real-world rail or road design.
The most important features of MapLineDraw are:
-
🎯 Interactive Spline Drawing
Click to place control points, drag them to adjust, and instantly see the resulting curve update in real time. -
🧩 Cubic B-splines (Degree 3)
Smooth paths with continuous curvature. -
📏 Automatic Geometry Analysis
The app calculates total curve length, minimum radius, and estimated maximum speed using typical comfort-based acceleration thresholds used in railway engineering. -
🔄 Open or Closed Curves
Usable for both routes and loops — you can do track modeling, circular paths, and more. -
📝 Project Metadata
Add a name, author, and description for your design ideas. -
📂 Download and Share
Save your projects to a custom .json file, which includes all curve geometry and metadata. Or, use shareable URLs to send your project directly to others. -
🎨 Customizable Legends
Color-coded curves, editable via the project JSON file to help clarify your visualizations.
Infrastructure design is no longer the exclusive domain of specialized, expensive CAD tools. With MapLineDraw, anyone can:
- Draft hypothetical rail corridors across regions
- Analyze existing road or rail curves for speed feasibility
- Trace real-world routes for measurement or export
- Sketch race track concepts, nature trails, or even fantasy transit systems
It's a tool built for hobbyists, students, planners, or open data advocates.
While MapLineDraw does not currently export GeoJSON or KML, it allows you to download your project in a custom JSON format. This includes:
- Curve type (open or closed)
- Degree of spline
- Control point coordinates (lat/lon)
- Project metadata and legend
Because the format is clean and structured, it's easy to convert into other formats using a simple script — or fork the project to add that feature.
MapLineDraw is fully open source under the MIT license. You can:
- View or contribute on GitHub: https://github.com/patrsc/MapLineDraw
- Suggest features or report bugs via issues
- Fork the project and customize it to your needs
MapLineDraw is not a professional-grade design tool. Its goal is simplicity, accessibility, and visual clarity, not engineering validation.
- No elevation (height) support (so no tunnels/bridges yet)
- No mobile browser optimization (best used on desktop)
- No built-in export to GIS formats (yet)
MapLineDraw provides a simple and free drawing tool for curves on a real map. Whether you're mapping out the next high-speed rail link or tracing an existing corridor for fun, it's a tool that helps ideas take shape — smoothly. Go to maplinedraw.com and start drawing.
If you like the tool or have suggestions how to improve it, feel free to contribute or open an issue on GitHub: https://github.com/patrsc/MapLineDraw.
