Editing Gift wrapping algorithm (section)

==Algorithm==
For the sake of simplicity, the description below assumes that the points are in [[general position]], i.e., no three points are [[collinear]]. The algorithm may be easily modified to deal with collinearity, including the choice whether it should report only  [[extreme point]]s (vertices of the convex hull) or all points that lie on the convex hull{{citation needed|reason=Link to a resource describing the details for these degenerate cases required.|date=March 2018}}. Also, the complete implementation must choose how to deal with [[degenerate case]]s when the convex hull has only 1 or 2 vertices, as well as with the issues of limited [[arithmetic precision]], both of computer computations and input data.
 
The gift wrapping algorithm begins with ''i''=0 and a point ''p<sub>0</sub>'' known to be on the convex hull, e.g., the leftmost point, and selects the point ''p<sub>i+1</sub>'' such that all points are to the right of the line ''p<sub>i</sub> p<sub>i+1</sub>''. This point may be found in ''O''(''n'') time by comparing [[Polar coordinate system|polar angle]]s of all points with respect to point ''p<sub>i</sub>'' taken for the center of [[polar coordinates]]. Letting ''i''=''i''+1, and repeating with until one reaches ''p<sub>h</sub>''=''p<sub>0</sub>'' again yields the convex hull in ''h'' steps.  In two dimensions, the gift wrapping algorithm is similar to the process of winding a string (or wrapping paper) around the set of points.

The approach can be extended to higher dimensions.