mirror of
https://github.com/wassname/PyCRS.git
synced 2026-07-14 01:10:36 +08:00
Karim Bahgat
124 lines
3.1 KiB
Python
124 lines
3.1 KiB
Python
|
|
import json
|
|
|
|
|
|
#################
|
|
# USER FUNCTIONS
|
|
#################
|
|
|
|
|
|
# parse from text strings
|
|
# possible use module: https://github.com/rockdoc/grabbag/wiki/CRS-WKT-Parser
|
|
# also note some paramter descriptions: http://www.geoapi.org/3.0/javadoc/org/opengis/referencing/doc-files/WKT.html
|
|
# and see gdal source code: http://gis.stackexchange.com/questions/129764/how-are-esri-wkt-projections-different-from-ogc-wkt-projections
|
|
|
|
def from_epsg_code(string):
|
|
# must go online (or look up local table) to get crs details
|
|
pass
|
|
|
|
def from_esri_code(string):
|
|
# must go online (or look up local table) to get crs details
|
|
pass
|
|
|
|
def from_sr_code(string):
|
|
# must go online (or look up local table) to get crs details
|
|
pass
|
|
|
|
def from_esri_wkt(string):
|
|
# parse arguments into components
|
|
# use args to create crs
|
|
pass
|
|
|
|
def from_ogc_wkt(string):
|
|
# parse arguments into components
|
|
# use args to create crs
|
|
pass
|
|
|
|
def from_unknown_wkt(string):
|
|
# detect if ogc wkt or esri wkt
|
|
# TIPS: esri wkt datums all use "D_" before the datum name
|
|
# then load with appropriate function
|
|
pass
|
|
|
|
def from_proj4(string):
|
|
# parse arguments into components
|
|
# use args to create crs
|
|
pass
|
|
|
|
def from_ogc_urn(string):
|
|
# hmmm, seems like ogc urn could be anything incl online link, epsg, etc...
|
|
# if necessary, must go online (or lookup local table) to get details
|
|
# maybe test which of these and run their function?
|
|
pass
|
|
|
|
def from_unknown_text(text):
|
|
# detect type and load with appropriate function
|
|
|
|
if string.startswith("urn:"):
|
|
from_ogc_urn(string)
|
|
|
|
elif string.startswith("+proj="):
|
|
from_proj4(string)
|
|
|
|
elif string.startswith("PROJCS["):
|
|
from_unknown_wkt(string)
|
|
|
|
elif string.startswith("EPSG:"):
|
|
from_epsg_code(string)
|
|
|
|
elif string.startswith("ESRI:"):
|
|
from_esri_code(string)
|
|
|
|
elif string.startswith("SR-ORG:"):
|
|
from_sr_code(string)
|
|
|
|
else: raise Exception("Could not detect which type of crs")
|
|
|
|
def from_geotiff_params(**params):
|
|
pass
|
|
|
|
|
|
|
|
|
|
# convenience methods for loading from different sources
|
|
|
|
def from_url(url, format=None):
|
|
# first get string from url
|
|
# ...
|
|
|
|
# then load
|
|
if format:
|
|
# load string using specified format
|
|
pass
|
|
else:
|
|
from_unknown_text(string)
|
|
|
|
def from_file(filepath):
|
|
if filepath.endswith(".prj"):
|
|
string = open(filepath, "r").read()
|
|
from_esri_wkt(string)
|
|
|
|
elif filepath.endswith((".geojson",".json")):
|
|
crsinfo = json.load(filepath)["crs"]
|
|
|
|
if crsinfo["type"] == "name":
|
|
string = crsinfo["properties"]["name"]
|
|
from_unknown_text(string)
|
|
|
|
elif crsinfo["type"] == "link":
|
|
url = crsinfo["properties"]["name"]
|
|
type = crsinfo["properties"].get("type")
|
|
from_url(url, format=type)
|
|
|
|
else: raise Exception("invalid geojson crs type: must be either name or link")
|
|
|
|
elif filepath.endswith((".tif",".tiff",".geotiff")):
|
|
pass
|
|
# ...
|
|
|
|
|
|
|
|
|
|
|
|
|