How to Calculate Centroid

Question

I am working with geospatial shapes and looking at the centroid algorithm here,

http://en.wikipedia.org/wiki/Centroid#Centroid_of_polygon

I have implemented the

Answer 1

public static Point GetCentroid( Point[ ] nodes, int count )
{
    int x = 0, y = 0, area = 0, k;
    Point a, b = nodes[ count - 1 ];

    for( int i = 0; i < count; i++ )
    {
        a = nodes[ i ];

        k = a.Y * b.X - a.X * b.Y;
        area += k;
        x += ( a.X + b.X ) * k;
        y += ( a.Y + b.Y ) * k;

        b = a;
    }
    area *= 3;

    return ( area == 0 ) ? Point.Empty : new Point( x /= area, y /= area );
}