def get_coords(self, zoom, x, y):
bounds = calculate_bounds(zoom, x, y)
az1, dec1, az2, dec2 = bounds
mid_az = (az2 - az1) / 2.0 + az1
mid_dec = (dec1 - dec2) / 2.0 + dec2
assert get_tile_coords((mid_az, mid_dec), zoom) == (x, y), get_tile_coords((mid_az, mid_dec), zoom)
radec = self.projector.unproject(AzAlt(mid_az, mid_dec))
#assert self.projector.project(radec) == AzAlt(mid_az, mid_dec), (self.projector.project(radec), AzAlt(mid_az, mid_dec))
cx, cy = get_tile_coords(radec, zoom)
return cx, cy, az1, az2, bounds, radec
def compose_tiles(projected_sky_objects):
start = time()
tiles = {}
for (p, r, mag, id) in projected_sky_objects:
for zoom in range(3, 10):
if mag < 4 + zoom:
x, y = get_tile_coords((p, r), zoom)
key = "%d-%d-%d" % (zoom, x, y)
if key not in tiles:
tiles[key] = []
tiles[key].append((p, r, mag, id))
print "completed tiling %d after %.1f seconds" % (len(tiles), time() - start)
averages = {}
for k in tiles:
z = k.split("-")[0]
if z not in averages:
averages[z] = (0, 0)
sum, count = averages[z]
sum = sum + len(tiles[k])
count = count + 1
averages[z] = (sum, count)
stats = {}
stats["total tiles"] = len(tiles)
for z in sorted(averages.keys()):
stats["zoom %d" % zoom] = "%d tiles %.1f avg objects/tile" % (count, sum/float(count))
return stats, tiles
def build_tile(params):
hparts, vparts, zoom, x, y = params
hparts_size = 24.0 / hparts
vparts_size = 180.0 / vparts
v1 = azalt_to_vector(0, 0)
v2 = azalt_to_vector(hparts_size, vparts_size)
min_distance = vector3_distance(v1, v2)
hour = ((x * hparts_size + hparts_size / 2.0) + 12) % 24
deg = 90 - y * vparts_size - vparts_size / 2.0
mid_v = azalt_to_vector(hour, deg)
tile_coords = get_tile_coords((hour, deg), zoom)
assert tile_coords == (x, y + vparts / 2), (tile_coords, (x, y + vparts / 2))
tile_id = "%s-%s-%s" % (zoom, x, y + vparts / 2)
tile_objects = []
for star in get_stars():
object_v = azalt_to_vector(star.ra, star.dec)
if vector3_distance(mid_v, object_v) <= min_distance:
obj = (star.id, star.ra, star.dec, star.mag)
# Some stars that are part of our constellations do not have
# B/F designation. Need to make sure they're shown at all zoom levels
if star.id in EXEMPTIONS and zoom >= EXEMPTIONS[star.id]:
tile_objects.append(obj)
continue
# Always show stars if they have a proper name or part of a constellation
# excluding Gliese designation
if star.bayer_flamsteed or star.proper_name:
tile_objects.append(obj)
continue
# All stars visible by zoom 7
if zoom >= 7:
tile_objects.append(obj)
continue
if star.mag <= 6 + (zoom - 5):
tile_objects.append(obj)
tile_objects.sort(key=lambda o: o[3], reverse=True)
print "Tile: %s Objects: %d" % (tile_id, len(tile_objects))
zpath = os.path.join("../indexes", str(zoom))
try:
os.mkdir(zpath)
except:
pass
f = open(os.path.join(zpath, "%s.dat"%tile_id), "wb")
try:
pickle.dump(tile_objects, f)
finally:
f.close()
def get_star(self, az, alt):
radec = self.projector.unproject(AzAlt(az, alt))
zoom = 6
cx, cy = get_tile_coords(radec, zoom)
objects = load_tile(zoom, cx, cy, cache=self.cache)
nearest = None
nearest_d = None
for id, ra, dec, mag in objects:
object_azalt = self.projector.project(RaDec(ra, dec))
distance = threed_distance(AzAlt(az, alt), object_azalt)
if (not nearest) or (nearest_d > distance):
nearest = (id, object_azalt)
nearest_d = distance
return nearest
def build_tile(params):
hparts, vparts, zoom, x, y = params
hparts_size = 24.0 / hparts
vparts_size = 180.0 / vparts
v1 = azalt_to_vector(0, 0)
v2 = azalt_to_vector(hparts_size, vparts_size)
min_distance = vector3_distance(v1, v2)
hour = ((x * hparts_size + hparts_size / 2.0) + 12) % 24
deg = 90 - y * vparts_size - vparts_size / 2.0
mid_v = azalt_to_vector(hour, deg)
tile_coords = get_tile_coords((hour, deg), zoom)
assert tile_coords == (x, y + vparts / 2), (tile_coords, (x, y + vparts / 2))
tile_id = "%s-%s-%s" % (zoom, x, y + vparts / 2)
tile_objects = []
print "Building", tile_id
for radec1, radec2 in get_all_lines():
p0 = azalt_to_vector(*radec1)
p1 = azalt_to_vector(*radec2)
segment = (p0, p1)
if point_to_segment_distance(mid_v, segment) <= min_distance:
tile_objects.append((radec1, radec2))
print "Tile: %s Objects: %d" % (tile_id, len(tile_objects))
zpath = os.path.join("../line-indexes", str(zoom))
try:
os.mkdir(zpath)
except:
pass
f = open(os.path.join(zpath, "%s.dat"%tile_id), "wb")
try:
pickle.dump(tile_objects, f)
finally:
f.close()
