Thuban/Model/proj.py

# Copyright (c) 2001 by Intevation GmbH
# Authors:
# Bernhard Herzog <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

__version__ = "$Revision$"

from Thuban import _

from types import StringTypes

import Projection
BaseProjection = Projection.Projection
del Projection

class Projection(BaseProjection):

    """A proj4 projection object that remembers the parameters"""

    def __init__(self, params, name = None):
        """Initialize the Projection with a list of 
        'parameter=value' strings and an optional name. If 'name' is
        None, the name will be set to 'Unknown' in the local language.
        """

        BaseProjection.__init__(self, params)

        if name is None:
            name = _("Unknown")

        self.params = params
        self.name = name

    def ForwardBBox(self, bbox):
        """Return the bounding box of the corners of the bounding box bbox
        """
        # This is not really the correct way to determine the bbox of a
        # projected shape, but for now it works well enough
        llx, lly, urx, ury = bbox
        xs = []; ys = []
        x, y = self.Forward(llx, lly)
        xs.append(x); ys.append(y)
        x, y = self.Forward(llx, ury)
        xs.append(x); ys.append(y)
        x, y = self.Forward(urx, ury)
        xs.append(x); ys.append(y)
        x, y = self.Forward(urx, lly)
        xs.append(x); ys.append(y)
        return min(xs), min(ys), max(xs), max(ys)

    def GetName(self):
        """Return the name of the projection."""
        return self.name

    def SetName(self, name):
        """Set the name of the projection."""
        if isinstance(name, StringTypes):
            self.name = name

    def GetParameter(self, param):
        """Return the projection value for the given parameter.

        If 'param' exists as a valid parameter then the returned
        value is a string with that value. If the parameter doesn't
        exist an empty string is returned.
        """

        for pair in self.params:
            p, v = pair.split("=")
            if p == param:
                return v

        return ""

    def GetAllParameters(self):
        """Return list of 'parameter=value' strings"""
        return self.params

    def __repr__(self):
        return self.name + ": " + repr(self.params)

class ProjFile:

    def __init__(self, filename):
        """Intialize the ProjFile.

        filename -- name of the file that this ProjFile represents.
        """

        self.__projs = []

        self.SetFilename(filename)
    
    def Add(self, proj):
        """Add the given projection to the end of the file. If 'proj'
        already exists, it is replaced in the same location as the
        original projection.
        """

        try:
            #
            # see if the projection already exists.
            # this only works if Projection doesn't override __eq__
            #
            self.__projs[self.__projs.index(proj)] = proj
        except ValueError:
            self.__projs.append(proj)

    def Remove(self, proj):
        """Remove the objection proj from the projection file.

        Raises a ValueError is proj is not found.
        """

        self.__projs.remove(proj)

    def GetFilename(self):
        """Return the filename where the ProjFile was read or will be
        written to.
        """

        return self.__filename

    def SetFilename(self, filename):
        """Set the filename where the ProjFile will be written to."""
        self.__filename = filename

    def GetProjections(self):
        """Return a list of the projections in the order they were read
        from the file or will be written.

        This is not a deep copy list, so any modifications made to the
        Projection objects will be written to the file.
        """

        return self.__projs

1	# Copyright (c) 2001 by Intevation GmbH
2	# Authors:
3	# Bernhard Herzog <[email protected]>
4	#
5	# This program is free software under the GPL (>=v2)
6	# Read the file COPYING coming with Thuban for details.
7
8	__version__ = "$Revision$"
9
10	from Thuban import _
11
12	from types import StringTypes
13
14	import Projection
15	BaseProjection = Projection.Projection
16	del Projection
17
18	class Projection(BaseProjection):
19
20	"""A proj4 projection object that remembers the parameters"""
21
22	def __init__(self, params, name = None):
23	"""Initialize the Projection with a list of
24	'parameter=value' strings and an optional name. If 'name' is
25	None, the name will be set to 'Unknown' in the local language.
26	"""
27
28	BaseProjection.__init__(self, params)
29
30	if name is None:
31	name = _("Unknown")
32
33	self.params = params
34	self.name = name
35
36	def ForwardBBox(self, bbox):
37	"""Return the bounding box of the corners of the bounding box bbox
38	"""
39	# This is not really the correct way to determine the bbox of a
40	# projected shape, but for now it works well enough
41	llx, lly, urx, ury = bbox
42	xs = []; ys = []
43	x, y = self.Forward(llx, lly)
44	xs.append(x); ys.append(y)
45	x, y = self.Forward(llx, ury)
46	xs.append(x); ys.append(y)
47	x, y = self.Forward(urx, ury)
48	xs.append(x); ys.append(y)
49	x, y = self.Forward(urx, lly)
50	xs.append(x); ys.append(y)
51	return min(xs), min(ys), max(xs), max(ys)
52
53	def GetName(self):
54	"""Return the name of the projection."""
55	return self.name
56
57	def SetName(self, name):
58	"""Set the name of the projection."""
59	if isinstance(name, StringTypes):
60	self.name = name
61
62	def GetParameter(self, param):
63	"""Return the projection value for the given parameter.
64
65	If 'param' exists as a valid parameter then the returned
66	value is a string with that value. If the parameter doesn't
67	exist an empty string is returned.
68	"""
69
70	for pair in self.params:
71	p, v = pair.split("=")
72	if p == param:
73	return v
74
75	return ""
76
77	def GetAllParameters(self):
78	"""Return list of 'parameter=value' strings"""
79	return self.params
80
81	def __repr__(self):
82	return self.name + ": " + repr(self.params)
83
84	class ProjFile:
85
86	def __init__(self, filename):
87	"""Intialize the ProjFile.
88
89	filename -- name of the file that this ProjFile represents.
90	"""
91
92	self.__projs = []
93
94	self.SetFilename(filename)
95
96	def Add(self, proj):
97	"""Add the given projection to the end of the file. If 'proj'
98	already exists, it is replaced in the same location as the
99	original projection.
100	"""
101
102	try:
103	#
104	# see if the projection already exists.
105	# this only works if Projection doesn't override __eq__
106	#
107	self.__projs[self.__projs.index(proj)] = proj
108	except ValueError:
109	self.__projs.append(proj)
110
111	def Remove(self, proj):
112	"""Remove the objection proj from the projection file.
113
114	Raises a ValueError is proj is not found.
115	"""
116
117	self.__projs.remove(proj)
118
119	def GetFilename(self):
120	"""Return the filename where the ProjFile was read or will be
121	written to.
122	"""
123
124	return self.__filename
125
126	def SetFilename(self, filename):
127	"""Set the filename where the ProjFile will be written to."""
128	self.__filename = filename
129
130	def GetProjections(self):
131	"""Return a list of the projections in the order they were read
132	from the file or will be written.
133
134	This is not a deep copy list, so any modifications made to the
135	Projection objects will be written to the file.
136	"""
137
138	return self.__projs
139
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svn:keywords	Author Date Id Revision