Convex Hull without the in-built function.

Hello, I want to do the convex hull algorithm without using the built-in function. I know i have to use atan2 fucntion and sort function and that I have to start from the poin with the lowest y-value. But other than that I don't have concrete plan as how to do it. Can anyone guide me?Also,

Answer 1

[Bjorn Gustavsson]

Take it step by step.

1, put points on paper.

2, work out how to step from the point with the smallest y-value to the next point along the perimeter in the counter-clock direction, what comparisons and conditions you need to make when selecting the next point, think this out graphically and write down the steps in pseudo-code on another paper.

3, progress to that next point and do the same for selecting the third point.

4, from this you should be able to work out a loop for this.

HTH

Answer 2

[Jan]

There are many known algorithms, which can inspire you. See https://en.wikipedia.org/wiki/Convex_hull_algorithms