/* Function: getArea
* -----------------
* Gets the area of a voronoi cell.
*/
private float getArea(VoronoiCell cell)
{
float area = 0.0f;
Vertex v1, v2;
for (int i = cell.halfEdges.Count - 1; i >= 0; i--)
{
HalfEdge he = cell.halfEdges[i];
v1 = he.getStartVertex();
v2 = he.getEndVertex();
area += v1.x * v2.y;
area -= v1.y * v2.x;
}
area /= 2.0f;
return(area);
}
/* Function: getCentroid
* ---------------------
* Gets the centroid of the cell.
*/
private Site getCentroid(VoronoiCell cell)
{
float x, y, mult;
x = y = 0.0f;
Vertex v1, v2;
for (int i = cell.halfEdges.Count - 1; i >= 0; i--)
{
HalfEdge he = cell.halfEdges[i];
v1 = he.getStartVertex();
v2 = he.getEndVertex();
mult = v1.x * v2.y - v1.y * v2.x;
x += (v1.x + v2.x) * mult;
y += (v1.y + v2.y) * mult;
}
mult = getArea(cell) * 6.0f;
return(new Site(x / mult, y / mult));
}