ideas
web frontend
- die INT-chart Grenzen (als Basis fuer ein download-tool) bekomme ich inzwischen auf den Schirm: http://kap.grade.de/int-chart-ol2.html , sicherlich verbesserungsbeduerftig
- workflow
- INT-Chart durch klick auf die Karte waehlen
- download iniziieren
- Weiterleitung auf neue Seite
- pruefen, ob und in welchem Format vorhanden
- wenn ja und nicht zu alt, downloadlinks anbieten
- wenn nein Job in queue-db schreiben
- number, name, bbox, scale, sessionid, ip-address, email, microtime, status=open, ...
- das ganze garnieren mit
- Pruefung, ob das script fuer diese karte schon in der Warteschlange ist
- Limitierung auf x downloads/jobs pro session ...
- email notifier
- captcha
prerequisites
tile server
- cronjob checkt queue-db alle x Minuten
- waehlt aeltesten job aus queue-db mit status=open
- tiledownload ueber proxy mit landez
- sinnvolles zoom-level anhand bbox errechnen (max. 10MB/chart)
- mbtiles erzeugen (siehe auch mbtiles implementation)
- stitchen und .png/.jpg erzeugen
- .kap mit imgkap erstellen
- ...
- status=done, zoom-level, date, ... in queue-db setzen
- temp-dir bereinigen und results in charts-dir kopieren
- erste Ergebnisse meiner Versuche: kap.grade.de
prerequisites
- apache
- tilestache
- nginx remote proxy
- imagemagick
- python
- imgkap
py script
import logging
import shutil
import math
from landez import MBTilesBuilder, ImageExporter, TilesManager
import sqlite3
import os
import sys
logging.basicConfig(level=logging.DEBUG)
# to be imported from sqlite-queue
con = sqlite3.connect('queue.sqlite')
with con:
con.row_factory = sqlite3.Row
cur = con.cursor()
cur.execute('SELECT * FROM jobs WHERE status="open" ORDER BY microtime DESC')
rows = cur.fetchall()
for row in rows:
sqMicrotime = row["Microtime"]
sqChart = row["Chart"]
sqName = row["Name"]
sqHO = row["HO"]
sqBottomGeoPre = row["BottomGeoPre"]
sqTopGeoPre = row["TopGeoPre"]
sqLeftGeoPre = row["LeftGeoPre"]
sqRightGeoPre = row["RightGeoPre"]
sqNumTiles16 = row["NumTiles16"]
# to be calculated from numtiles16, numtiles < 700
# numtiles16 is right now hardcoded at int-chart.gejson for ol depth of view reasons, there might be smarter ways in future
# https://github.com/makinacorpus/landez/issues/44
myNumTiles = sqNumTiles16 * 4 * 4
myZoom = 18
while (myNumTiles > 4):
myNumTiles = myNumTiles / 4
myZoom = myZoom - 1
# settings
# myUrlBase = "http://tiles.grade.de/tiles.py/openriverboatmap/{z}/{x}/{y}.png"
myUrlBase = "http://otile1.mqcdn.com/tiles/1.0.0/map/{z}/{x}/{y}.jpg"
myUrlSeamark = "http://tiles.grade.de/tiles.py/seamark/{z}/{x}/{y}.png"
if sqHO == "DE":
myUrlHydro = "http://tiles.grade.de/tiles.py/NAUTHIS_SkinOfEarth/{z}/{x}/{y}.png"
elif sqHO== "NL/GB":
myUrlHydro = "http://tiles.grade.de/tiles.py/ncp_diepte14/{z}/{x}/{y}.png"
else:
myUrlHydro = ""
myFileName = str(sqMicrotime)
myMbtilesFile = myFileName + ".mbtiles"
myImageFile = myFileName + ".jpg"
myKapFile = myFileName + ".kap"
myTextFile = myFileName + ".txt"
myBbox = (sqLeftGeoPre, sqBottomGeoPre, sqRightGeoPre, sqTopGeoPre)
myZoomLevels = [myZoom]
myZoomLevel = myZoom
myTileSize = 256
#myTileFormat = 'image/png'
myTileFormat = 'image/jpeg'
# download and mbtiles build
mb = MBTilesBuilder(tiles_url=myUrlBase, cache=True, filepath=myMbtilesFile, tile_size=myTileSize, tile_format=myTileFormat)
mb.add_coverage(myBbox, myZoomLevels)
if myUrlHydro != "":
hydro = TilesManager(tiles_url=myUrlHydro)
seamark = TilesManager(tiles_url=myUrlSeamark)
hydro.add_layer(seamark)
overlay = hydro
else:
seamark = TilesManager(tiles_url=myUrlSeamark)
overlay = seamark
mb.add_layer(overlay)
mb.run(force=True)
# export image from mbtiles
# not the best idea: causes IO at temp dir, again
ie = ImageExporter(mbtiles_file=myMbtilesFile)
ie.export_image(myBbox, myZoomLevel, imagepath=myImageFile)
# save the geoinfo
myGrid = ie.grid_tiles(myBbox, myZoomLevel)
sqWidth = len(myGrid[0])
sqHeight = len(myGrid)
sqWidthPix = sqWidth * myTileSize
sqHeightPix = sqHeight * myTileSize
# delete temp dir (ImageExporter does not!)
# bad: path is hard coded. how do I get hold of landez's temp path?
# https://github.com/makinacorpus/landez/issues/42
try:
shutil.rmtree('/tmp/landez')
except OSError:
pass
# geoinfo output
logging.debug(" grid: " + str(myGrid))
myLeftColumn = myGrid[0]
myTopLeft = myLeftColumn[0]
sqLeftTile = myTopLeft[0]
sqTopTile = myTopLeft[-1]
myRightColumn = myGrid[-1]
myBottomRight = myRightColumn[-1]
sqRightTile = myBottomRight[0]
sqBottomTile = myBottomRight[-1]
# calculate coords from tilenumbers
def num2deg(xtile, ytile, zoom):
n = 2.0 ** zoom
lon_deg = -180.0 + 360.0 * xtile / n
lat_rad = math.atan(math.sinh(math.pi * (1.0 - 2.0 * (ytile / n))))
lat_deg = 180.0 * lat_rad / math.pi
return (lon_deg, lat_deg)
sqBottomGeoPost = (num2deg(sqRightTile + 1, sqBottomTile + 1, myZoom)[-1])
sqTopGeoPost = (num2deg(sqLeftTile, sqTopTile, myZoom)[-1])
sqLeftGeoPost = (num2deg(sqLeftTile, sqTopTile, myZoom)[0])
sqRightGeoPost = (num2deg(sqRightTile + 1, sqBottomTile + 1, myZoom)[0])
# shall be exported to sqlite-queue
logging.debug(" baselayer: " + str(myUrlBase))
logging.debug(" seamark: " + str(myUrlSeamark))
logging.debug(" hydro: " + str(myUrlHydro))
logging.debug(" zoom: " + str(myZoom))
logging.debug(" width: " + str(sqWidth) + " tiles")
logging.debug(" height: " + str(sqHeight) + " tiles")
logging.debug(" widthpix: " + str(sqWidthPix) + " pixel")
logging.debug(" heightpix: "+ str(sqHeightPix) + " pixel")
logging.debug(" left tile " + str(sqLeftTile))
logging.debug(" right tile: " + str(sqRightTile))
logging.debug(" top tile: " + str(sqTopTile))
logging.debug(" bottom tile: "+ str(sqBottomTile))
logging.debug(" left: " + str(sqLeftGeoPost))
logging.debug(" right: " + str(sqRightGeoPost))
logging.debug(" top: " + str(sqTopGeoPost))
logging.debug(" bottom: " + str(sqBottomGeoPost))
sqPost = [
'UrlBase="' + str(myUrlBase) + '"',
'UrlSeamark="' + str(myUrlSeamark) + '"',
'UrlHydro="' + str(myUrlHydro) + '"',
'Zoom=' + str(myZoom),
'BottomGeoPost='+ str(sqBottomGeoPost),
'TopGeoPost='+ str(sqTopGeoPost),
'LeftGeoPost='+ str(sqLeftGeoPost),
'RightGeoPost='+ str(sqRightGeoPost),
'status="done"'
]
t = ", "
sqPost = t.join(sqPost)
sqlUpdate = "UPDATE jobs " + "SET " + str(sqPost) + " WHERE Microtime=" + str(sqMicrotime)
logging.debug(" sqlUpdate: " + str(sqlUpdate))
con = sqlite3.connect('queue.sqlite')
with con:
con.row_factory = sqlite3.Row
cur = con.cursor()
cur.execute(sqlUpdate)
con.commit()
logging.debug(" Number of rows updated: " + str(cur.rowcount))
# start imgkap to generate .kap file
import subprocess
myImgkapCall = "./imgkap " + myImageFile + " " + str(sqTopGeoPost) + " " + str(sqLeftGeoPost) + " " + str(sqBottomGeoPost) + " " + str(sqRightGeoPost) + " " + myKapFile
print myImgkapCall
subprocess.call(myImgkapCall, shell=True)
# write textfile
txtPost = [
'INT Chart Number= ' + sqChart,
'INT Chart Name= ' + sqName,
'',
'Copyright Notices:',
'Base Layer= http://developer.mapquest.com/de/web/products/open/map',
'Seamark Layer= http://www.openseamap.org/',
'DE Hydrography= http://gdiwiki.bsh.de/wiki/index.php/NAUTHIS_Skin_Of_The_Earth',
'NL Hydrography= http://www.rijkswaterstaat.nl/zakelijk/databestanden/online_geografische_gegevens_rijkswaterstaat/',
'',
'Zoom Level= ' + str(myZoom),
'',
'Bottom= '+ str(sqBottomGeoPost),
'Top= '+ str(sqTopGeoPost),
'Left= '+ str(sqLeftGeoPost),
'Right= '+ str(sqRightGeoPost),
'',
'width= ' + str(sqWidth) + ' tiles',
'height= ' + str(sqHeight) + ' tiles',
'width= ' + str(sqWidthPix) + ' pixel',
'height= ' + str(sqHeightPix) + ' pixel',
'',
'left tile number= ' + str(sqLeftTile),
'right tile number= ' + str(sqRightTile),
'top tile number= ' + str(sqTopTile),
'bottom tile number= '+ str(sqBottomTile)
]
t = "\n"
txtPost = t.join(txtPost)
logging.debug(" txtPost: " + str(txtPost))
with open(myTextFile, 'w') as f:
f.write(txtPost)
# move and rename files
myPath = "../INT-CHART/INT-"
myNotice = "_MapQuest-OSeaM-BSH"
myNewMbtilesFile = myPath + sqChart + myNotice + ".mbtiles"
myNewImageFile = myPath + sqChart + myNotice + ".jpg"
myNewKapFile = myPath + sqChart + myNotice + ".kap"
myNewTextFile = myPath + sqChart + myNotice + ".txt"
try:
os.rename (myMbtilesFile, myNewMbtilesFile)
os.remove(myMbtilesFile)
except OSError:
pass
try:
os.rename (myImageFile, myNewImageFile)
os.remove(myImageFile)
except OSError:
pass
try:
os.rename (myKapFile, myNewKapFile)
os.remove(myKapFile)
except OSError:
pass
try:
os.rename (myTextFile, myNewTextFile)
os.remove(myTextFile)
except OSError:
pass
Reason for ChartBundler
- Lets talk a bit about amounts here and not low stress or high stress. Using the charts offline on a mobile device. Lets say the display is about 1024x1024 Pixel, then we will need at least 16 tiles per map. If we start on zoom level 8 with the bounding box and continue to zoom level 16 for the harbours, we need around 2 Mio tiles. This 16 tiles on zoom level 8 is about the northern Adria. If we want the Channel just skipping Lands End up to the belgian coast, this would be 6 by 5 on zoom level 8. --Alexej
- Hi Alexej, do not understand this paragraph!? 2 test datasets of mine:
- INT-1463 bei zoom-level 13 (s="53.7" n="54.25" w="7.4" e="9.05"):
x: 37
y: 21
total: 777
[1]
- river Ruhr
zoomlevel=16
~ 370 tiles
[2]
- --Kannix (Diskussion) 16:22, 29. Jan. 2015 (UTC)
