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import os |
import os |
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import os.path |
import os.path |
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import weakref |
import weakref |
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import traceback |
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import Thuban |
import Thuban |
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from Thuban import _ |
from Thuban import _ |
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PROJ_EXT = ".proj" |
PROJ_EXT = ".proj" |
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has_gdal_support = lambda: False |
# Determine the status of GDAL support. If GDAL is supported |
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try: |
# gdal_support_status will be set to the empty string, otherwise to a |
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# first try to see if our extension module is there. if it |
# string with information why it isn't supported |
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# wasn't even compiled, we obviously don't have gdal support. |
# |
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import gdalwarp |
# GDAL is supported if we can import both the thuban specific gdalwarp |
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# module and the GDAL python bindings. |
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# now try to import the python extension. if this doesn't |
for _module in ("gdalwarp", "gdal"): |
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# exist then we can't do anything. |
try: |
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import gdal |
__import__(_module) |
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|
except ImportError, val: |
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"""Return True if the gdal library is available.""" |
gdal_support_status = (_("No GDAL support because module '%s'" |
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has_gdal_support = lambda: True |
" cannot be imported. Python exception: '%s'") |
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except ImportError: |
% (_module, str(val))) |
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pass |
break |
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else: |
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gdal_support_status = "" |
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def has_gdal_support(): |
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return gdal_support_status == "" |
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projfile_cache = weakref.WeakValueDictionary() |
projfile_cache = weakref.WeakValueDictionary() |
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saver = ProjFileSaver(pf) |
saver = ProjFileSaver(pf) |
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saver.write(pf.GetFilename()) |
saver.write(pf.GetFilename()) |
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# |
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def get_system_proj_file(): |
# Constants for the get_system_proj_file function |
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"""Return the standard projections and a list with warnings |
# |
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|
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The projections read from the default thuban projection file |
# The default projection file with a few predefined projections |
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(usually in Resources/Projections/defaults.proj). The return value |
DEFAULT_PROJ_FILE = "defaults.proj" |
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is a tuple with the projections in a ProjFile object and a list of |
|
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strings with warning messages. The warnings list is usually empty |
# The epsg projections. |
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but may contain messages about ignored errors. |
EPSG_PROJ_FILE = "epsg.proj" |
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# Deprecated EPSG projections. |
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EPSG_DEPRECATED_PROJ_FILE = "epsg-deprecated.proj" |
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def get_system_proj_file(filename): |
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"""Return the projections from the indicated file and a list with warnings |
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The filename argument should be the name of a file in the directory |
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with Thuban's default projection files (Resources/Projections/). If |
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possible callers should not use hardwired string literal for the |
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name to avoid unnecessary duplication. Instead they should use one |
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of the predefined constants, currently DEFAULT_PROJ_FILE, |
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EPSG_PROJ_FILE or EPSG_DEPRECATED_PROJ_FILE. |
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The return value is a tuple with the projections in a ProjFile |
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object and a list of strings with warning messages. The warnings |
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list is usually empty but may contain messages about ignored errors. |
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If the file could could not be opened return an empty projection |
If the file could could not be opened return an empty projection |
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file object set to store data in the default file. |
file object set to store data in the indicated default file. |
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""" |
""" |
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filename = os.path.join(projdir, "defaults.proj") |
fullname = os.path.join(projdir, filename) |
132 |
try: |
try: |
133 |
return read_proj_file(filename) |
return read_proj_file(fullname) |
134 |
except (OSError, IOError, SAXParseException), val: |
except (OSError, IOError, SAXParseException), val: |
135 |
msg = _('Could not read "%s": %s') % (filename, str(val)) |
msg = _('Could not read "%s": %s') % (fullname, str(val)) |
136 |
return ProjFile(filename), [msg] |
return ProjFile(fullname), [msg] |
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|
138 |
def get_user_proj_file(): |
def get_user_proj_file(): |
139 |
"""Return the user's projections and a list with warnings |
"""Return the user's projections and a list with warnings |