display maps color-coded by intersection connectivity

rift.py

import sqlite3

def main(osmdb_name, gdb_name,map_filename):
    osmdb = sqlite3.connect(osmdb_name)
    gdb = sqlite3.connect(gdb_name)
    
    c = gdb.cursor()
    
    c.execute( "select vertex1, count(*) from edges where vertex1 LIKE 'osm%' group by vertex1" )
    
    intersection_counts = dict(list(c))
    
    c.close()
    
    c = osmdb.cursor()
    
    c.execute("""select min(lon),min(lat),max(lon),max(lat) from nodes""")

    ll,bb,rr,tt = list(c)[0]

    from prender import processing
    mr = processing.MapRenderer()
    mr.start(ll,bb,rr,tt,3000) #left,bottom,right,top,width
    mr.background(255,255,255)
    mr.strokeWeight(0.001)
    mr.smooth()
    
    c.execute( "select id,lat,lon from nodes where endnode_refs>1" )
    
    for id,lat,lon in c:
        if "osm-%s"%id in intersection_counts:
            count=intersection_counts["osm-%s"%id]
            
            if(count==3):
                mr.stroke(64,64,64)
            elif(count==4):
                mr.stroke(255,0,0)
            elif(count>2):
                mr.stroke(128,128,128)
            else:
                continue
            
            mr.point( lon,lat )
            print id,lat,lon,intersection_counts["osm-%s"%id]
            
    c.close()

    mr.saveLocal(map_filename)
    mr.stop()
    
if __name__=='__main__':
    main('/home/brandon/Desktop/pugetsound/pugetsound.osmdb','/home/brandon/Desktop/pugetsound/pugetsound.gdb',"/home/brandon/Desktop/pugetsound/map.png")