recompute_points.py

def pointPhysics():
    global pts # array of points on a sphere, specified as (lat,lon) pairs
    new_pts = []
    for i in xrange(nbrPoints):
        (clat,clon) = pts[i] # center point for gnomonic projection (projects to 0,0)
        fx,fy = (0,0)
        for j in xrange(nbrPoints):
            if j == i:
                continue
            jlat,jlon = pts[j]
            hd = haversine(pts[i],pts[j])
            if hd < maxInfluence:
                force = map(pow(hd/maxInfluence,2),0,1,1,0) * iScale  # closer points have more influence..
                gx,gy = gnomic(jlat,jlon,clat,clon)
                d = sqrt(gx**2 + gy**2) # dist(0,0,gx,gy)
                nfx,nfy =  -(gx/d)*force,-(gy/d)*force
                fx += nfx
                fy += nfy
        new_pts.append( ignomic(fx,fy,clat,clon) )
        
    pts = new_pts