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:
            self.name = _("Unknown")
        elif isinstance(name, StringTypes):
            self.name = name

        self.params = params

    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 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 object proj from the projection file.

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

        self.__projs.remove(proj)

    def Replace(self, oldproj, newproj):
        """Replace the object 'oldproj' with 'newproj'.
        
        Raises ValueError if oldproj is not in the file.
        """

        #
        # see if the projection already exists.
        # this only works if Projection doesn't override __eq__
        #
        self.__projs[self.__projs.index(oldproj)] = newproj

    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	self.name = _("Unknown")
32	elif isinstance(name, StringTypes):
33	self.name = name
34
35	self.params = params
36
37	def ForwardBBox(self, bbox):
38	"""Return the bounding box of the corners of the bounding box bbox
39	"""
40	# This is not really the correct way to determine the bbox of a
41	# projected shape, but for now it works well enough
42	llx, lly, urx, ury = bbox
43	xs = []; ys = []
44	x, y = self.Forward(llx, lly)
45	xs.append(x); ys.append(y)
46	x, y = self.Forward(llx, ury)
47	xs.append(x); ys.append(y)
48	x, y = self.Forward(urx, ury)
49	xs.append(x); ys.append(y)
50	x, y = self.Forward(urx, lly)
51	xs.append(x); ys.append(y)
52
53	return min(xs), min(ys), max(xs), max(ys)
54
55	def GetName(self):
56	"""Return the name of the projection."""
57	return self.name
58
59	def GetParameter(self, param):
60	"""Return the projection value for the given parameter.
61
62	If 'param' exists as a valid parameter then the returned
63	value is a string with that value. If the parameter doesn't
64	exist an empty string is returned.
65	"""
66
67	for pair in self.params:
68	p, v = pair.split("=")
69	if p == param:
70	return v
71
72	return ""
73
74	def GetAllParameters(self):
75	"""Return list of 'parameter=value' strings"""
76	return self.params
77
78	def __repr__(self):
79	return self.name + ": " + repr(self.params)
80
81	class ProjFile:
82
83	def __init__(self, filename):
84	"""Intialize the ProjFile.
85
86	filename -- name of the file that this ProjFile represents.
87	"""
88
89	self.__projs = []
90
91	self.SetFilename(filename)
92
93	def Add(self, proj):
94	"""Add the given projection to the end of the file. If 'proj'
95	already exists, it is replaced in the same location as the
96	original projection.
97	"""
98
99	try:
100	#
101	# see if the projection already exists.
102	# this only works if Projection doesn't override __eq__
103	#
104	self.__projs[self.__projs.index(proj)] = proj
105	except ValueError:
106	self.__projs.append(proj)
107
108	def Remove(self, proj):
109	"""Remove the object proj from the projection file.
110
111	Raises a ValueError is proj is not found.
112	"""
113
114	self.__projs.remove(proj)
115
116	def Replace(self, oldproj, newproj):
117	"""Replace the object 'oldproj' with 'newproj'.
118
119	Raises ValueError if oldproj is not in the file.
120	"""
121
122	#
123	# see if the projection already exists.
124	# this only works if Projection doesn't override __eq__
125	#
126	self.__projs[self.__projs.index(oldproj)] = newproj
127
128	def GetFilename(self):
129	"""Return the filename where the ProjFile was read or will be
130	written to.
131	"""
132
133	return self.__filename
134
135	def SetFilename(self, filename):
136	"""Set the filename where the ProjFile will be written to."""
137	self.__filename = filename
138
139	def GetProjections(self):
140	"""Return a list of the projections in the order they were read
141	from the file or will be written.
142
143	This is not a deep copy list, so any modifications made to the
144	Projection objects will be written to the file.
145	"""
146
147	return self.__projs
148
Name	Value
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svn:keywords	Author Date Id Revision