Function graham_scan 

pub fn graham_scan<O, T>(
    points: &[Point2<T>],
    assume_sorted: bool,
    voxel_size: Option<O>,
) -> Option<Vec<Point2<T>>>
where
    O: AsPrimitive<isize> + ComplexField + Copy + PartialOrd,
    T: AsPrimitive<O> + Debug + IsNan + NumAssign + PartialOrd,
    usize: AsPrimitive<T>,

Computes the convex hull of a set of points using the Graham Scan algorithm. Specifically the Monotone Chain variant This version sorts the points lexicographically before computing the convex hull. A downside of using this algorithm is that it does not handle collinear points well.

Arguments

• points - A slice of points to compute the convex hull of
• assume_sorted - A boolean indicating whether the points are already sorted lexicographically, this is critical for correctness so make sure you don’t set this to true unless you are sure the points are sorted
• voxel_size - An optional parameter specifying the voxel size by which to downsample the point cloud before computing the convex hull, useful in reducing errors due to close or identical vertices.

Genericsoc -

• O - The output type of the trigonometric functions, essentially the precision of the calculations
• T - The type of the points, can be of any scalar type

Returns

An Option of Vec<Point2<T>> representing the convex hull, or None if there were not enough points to compute a convex hull, or if all points are collinear