def preview_url(ul, ur, lr, ll):
'''
'''
merc = MercatorProjection(0)
ul = merc.rawUnproject(Point(*ul))
ur = merc.rawUnproject(Point(*ur))
lr = merc.rawUnproject(Point(*lr))
ll = merc.rawUnproject(Point(*ll))
q = dict(width='512', height='384', module='map')
ulx, uly, urx, ury, lrx, lry, llx, lly \
= [rad2deg(v) for v in (ul.x, ul.y, ur.x, ur.y, lr.x, lr.y, ll.x, ll.y)]
xmin, ymin = min(ulx, urx, lrx, llx), min(uly, ury, lry, lly)
xmax, ymax = max(uly, ury, lry, lly), max(ulx, urx, lrx, llx)
perimeter = (ulx, uly, urx, ury, lrx, lry, llx, lly, ulx, uly)
q.update(dict(polygons=','.join(['%.4f' % v for v in perimeter])))
q.update(
dict(bbox=','.join(('%.4f' % xmin, '%.4f' % ymax, '%.4f' % xmax,
'%.4f' % ymin))))
return 'http://pafciu17.dev.openstreetmap.org/?' + urlencode(q)
def calculate_corners(aspect, x, y, size, theta):
''' Return latitude, longitude corners for a geometric placement.
'''
merc = MercatorProjection(0)
#
# Get the natural angle of the hypotenuse from map aspect ratio,
# measured from the lower-right to the upper-left corner and expressed
# in CCW radians from due east.
#
base_theta = atan2(1, -float(aspect))
#
# Derive center-to-corners offset from natural angle and placement theta.
#
place_theta = base_theta + theta
dx = sin(place_theta - pi/2) * size/2
dy = cos(place_theta - pi/2) * size/2
ul = Point(x - dx, y + dy)
lr = Point(x + dx, y - dy)
#
# Convert back to degree latitude and longitude
#
ul = merc.rawUnproject(ul)
lr = merc.rawUnproject(lr)
ul_lat, ul_lon = rad2deg(ul.y), rad2deg(ul.x)
lr_lat, lr_lon = rad2deg(lr.y), rad2deg(lr.x)
return ul_lat, ul_lon, lr_lat, lr_lon
def preview_url(ul, ur, lr, ll):
'''
'''
merc = MercatorProjection(0)
ul = merc.rawUnproject(Point(*ul))
ur = merc.rawUnproject(Point(*ur))
lr = merc.rawUnproject(Point(*lr))
ll = merc.rawUnproject(Point(*ll))
q = dict(width='512', height='384', module='map')
ulx, uly, urx, ury, lrx, lry, llx, lly \
= [rad2deg(v) for v in (ul.x, ul.y, ur.x, ur.y, lr.x, lr.y, ll.x, ll.y)]
xmin, ymin = min(ulx, urx, lrx, llx), min(uly, ury, lry, lly)
xmax, ymax = max(uly, ury, lry, lly), max(ulx, urx, lrx, llx)
perimeter = (ulx, uly, urx, ury, lrx, lry, llx, lly, ulx, uly)
q.update(dict(polygons=','.join(['%.4f' % v for v in perimeter])))
q.update(dict(bbox=','.join(('%.4f' % xmin, '%.4f' % ymax, '%.4f' % xmax, '%.4f' % ymin))))
return 'http://pafciu17.dev.openstreetmap.org/?' + urlencode(q)
