[postgis-users] Centroid Within Multi Part Polygon

[Rob Agar]

hi Simon

Simon Greener wrote:
 > Someone asked recently about a centroid function which guaranteed that
 > the created centroid:
 >
 > 1. Fell within a polygon (not outside it as is the case with
 > implementations that average the X and Y coords of an area);
 > 2. If the polygon is multi-part, put the centroid in the largest part.
 >
 > I have just such a function


Out of curiosity, where would your function place the centroid of a (2D) 
doughnut?

Rob