Point in Polygon for a trilateration fix
Built for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field. Simulate a trilateration fix live below — adjust the inputs and watch it respond, right in your browser.
Controls
Is a point inside a shape? The ray-casting algorithm shoots a ray from the point in any direction and counts how many polygon edges it crosses: an odd number means inside, an even number means outside. It is the math behind geofencing — triggering an alert when a phone or vehicle enters or leaves a region — and behind hit-testing in graphics. Drag the point, or click anywhere to move it there.
Data Inspector
Governing equation
Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.
More with Point in Polygon
Frequently asked questions
- Is this good for first responders?
- Yes — this version of "Point in Polygon for a trilateration fix" is framed for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field.
- Do I need to install anything?
- No. It runs in any modern browser, free, with no account required.