# Hedra: Wrap the points in their tightest shape

> Andrew's monotone-chain hull, shoelace area, point-in-polygon, and segment intersection - all from the cross product. 13 tests, including a property-based fuzz that the hull is convex, encloses every point, and is minimal.

Hedra is a computational-geometry toolkit that wraps a set of points in their tightest enclosing shape and answers related spatial questions. The signature technique is Andrew's monotone-chain convex hull, with shoelace area, point-in-polygon, and segment intersection all derived from the cross product, plus a property-based fuzz test proving the hull is convex, encloses every point, and is minimal. It is a from-scratch, dependency-light build you can download and run locally.

## About the app

Computational geometry

## What to take away

- Andrew's monotone-chain hull, shoelace area, point-in-polygon, and segment intersection - all from the cross product. 13 tests, including a property-based fuzz that the hull is convex, encloses every point, and is minimal.
- Download: Hedra (ZIP)

## Tags

Free software, Hedra

## Read the full write-up

/downloads/hedra.zip

## Terms used in this piece

- https://dfieldsolutions.com/en/glossary/fuzz.md

## We build this for clients

https://dfieldsolutions.com/en/services/full-stack

## More from the lab

- https://dfieldsolutions.com/en/lab/sylex.md — Sylex: Make sense of the slashes
- https://dfieldsolutions.com/en/lab/kindra.md — Kindra: Miss a beat, not the rhythm
- https://dfieldsolutions.com/en/lab/voxara.md — Voxara: Argue better. Lose gracefully
- https://dfieldsolutions.com/en/lab/wraithward.md — Wraithward: Spot the bait before you bite

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Source: https://dfieldsolutions.com/en/lab/hedra
DField Solutions — Torony köz 5-1.a, 2120 Dunakeszi, Hungary — +36 20 722 0002 — dezso@dfieldsolutions.com
Booking: see https://dfieldsolutions.com/en/contact