Coding Challenge

In this coding challenge, I implement the “Gift Wrapping algorithm” (aka Jarvis march) for calculating a convex hull in JavaScript. This is a foundational topic in computational geometry! Code: https://thecodingtrain.com/challenges...

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References:
🌐 Gift Wrapping Algorithm: https://en.wikipedia.org/wiki/Gift_wr...
🌐 Cross Product: https://en.wikipedia.org/wiki/Cross_p...
📝 The splice() Array Function: https://developer.mozilla.org/en-US/d...

Videos:
🎥 ES6 Arrow Syntax:    • 16.3: ES6 Arrow Function - Topics of JavaS...  
🔴 Coding Train Live 180:    • Coding Train Live 180: Processing Java Lib...  

Timestamps:
00:00 Introduction
00:47 What is a Convex Hull?
02:36 The Gift Wrapping Algorithm
03:50 Animated Example of the Algorithm
04:58 Time Complexity of this Algorithm
05:30 Code! Drawing Random Points
05:42 Find the Leftmost Point
07:05 Set up Variables for the Animation
09:03 Make a Guess about the Next Point
10:58 Find out which Vector is “to the Left”
15:00 Add Spacing around the Points
15:33 Add an Exit Condition
15:54 Add the Next Vertex to the Hull
16:26 Draw the Hull
17:12 Continue the Algorithm with the Vertices
18:33 Check when the Algorithm is Done
19:08 Mutating the Array is not necessary
19:50 Watching the Algorithm with More Points
20:13 Inefficiencies about this Algorithm
20:29 Closing the Shape
20:54 (Gift) Wrapping up this Coding Challenge

Editing by Mathieu Blanchette
Animations by Jason Heglund
Music from Epidemic Sound

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🔗 Processing: https://processing.org

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#algorithm #computationalgeometry #convexhull #p5js #javascript