Thuban/Model/layer.py

# Copyright (c) 2001, 2002, 2003 by Intevation GmbH
# Authors:
# Bernhard Herzog <[email protected]>
# Jonathan Coles <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

__version__ = "$Revision$"

from math import log, ceil

from Thuban import _

import shapelib, shptree

import gdal
from gdalconst import GA_ReadOnly

from messages import LAYER_PROJECTION_CHANGED, LAYER_VISIBILITY_CHANGED, \
     LAYER_CHANGED

from color import Color

import classification

from base import TitledObject, Modifiable


class Shape:

    """Represent one shape"""

    def __init__(self, points):
        self.points = points
        #self.compute_bbox()
        self.bbox = None

    def compute_bbox(self):
        if self.bbox is not None:
            return self.bbox

        xs = []
        ys = []
        for x, y in self.points:
            xs.append(x)
            ys.append(y)
        self.llx = min(xs)
        self.lly = min(ys)
        self.urx = max(xs)
        self.ury = max(ys)

        self.bbox = (self.llx, self.lly, self.urx, self.ury)

        return self.bbox

    def Points(self):
        return self.points


# Shape type constants
SHAPETYPE_POLYGON = "polygon"
SHAPETYPE_ARC = "arc"
SHAPETYPE_POINT = "point"

# mapping from shapelib shapetype constants to our constants
shapelib_shapetypes = {shapelib.SHPT_POLYGON: SHAPETYPE_POLYGON,
                       shapelib.SHPT_ARC: SHAPETYPE_ARC,
                       shapelib.SHPT_POINT: SHAPETYPE_POINT}

shapetype_names = {SHAPETYPE_POINT: "Point",
                   SHAPETYPE_ARC: "Arc",
                   SHAPETYPE_POLYGON: "Polygon"}

class BaseLayer(TitledObject, Modifiable):

    """Base class for the layers."""

    def __init__(self, title, visible = True, projection = None):
        """Initialize the layer.

        title -- the title
        visible -- boolean. If true the layer is visible.
        """
        TitledObject.__init__(self, title)
        Modifiable.__init__(self)
        self.visible = visible
        self.projection = projection

    def Visible(self):
        """Return true if layer is visible"""
        return self.visible

    def SetVisible(self, visible):
        """Set the layer's visibility."""
        self.visible = visible
        self.issue(LAYER_VISIBILITY_CHANGED, self)

    def HasClassification(self):
        """Determine if this layer support classifications."""
        return False

    def GetProjection(self):
        """Return the layer's projection."""
        return self.projection

    def SetProjection(self, projection):
        """Set the layer's projection"""
        self.projection = projection
        self.changed(LAYER_PROJECTION_CHANGED, self)

class Layer(BaseLayer):

    """Represent the information of one geodata file (currently a shapefile)

    All children of the layer have the same type.

    A layer has fill and stroke colors. Colors should be instances of
    Color. They can also be None, indicating no fill or no stroke.

    The layer objects send the following events, all of which have the
    layer object as parameter:

        TITLE_CHANGED -- The title has changed.
        LAYER_PROJECTION_CHANGED -- the projection has changed.
    """

    def __init__(self, title, data, projection = None,
                 fill = Color.Transparent, 
                 stroke = Color.Black, 
                 lineWidth = 1, 
                 visible = True):
        """Initialize the layer.

        title -- the title
        data -- datastore object for the shape data shown by the layer
        projection -- the projection object. Its Inverse method is
               assumed to map the layer's coordinates to lat/long
               coordinates
        fill -- the fill color or Color.Transparent if the shapes are 
                not filled
        stroke -- the stroke color or Color.Transparent if the shapes 
                are not stroked
        visible -- boolean. If true the layer is visible.

        colors are expected to be instances of Color class
        """
        BaseLayer.__init__(self, title, 
                                 visible = visible,
                                 projection = projection)

        #
        # this is really important so that when the classification class
        # tries to set its parent layer the variable will exist
        #
        self.__classification = None
        self.__setClassLock = False

        self.SetShapeStore(data)

        self.SetClassification(None)

        self.__classification.SetDefaultLineColor(stroke)
        self.__classification.SetDefaultLineWidth(lineWidth)
        self.__classification.SetDefaultFill(fill)
        self.__classification.SetLayer(self)

        self.UnsetModified()


    def SetShapeStore(self, store):
        self.store = store
        self.shapefile = self.store.Shapefile()
        self.shapetable = self.store.Table()
        if hasattr(self.store, "FileName"):
            self.filename = self.store.FileName()
        self.table = self.shapetable

        numshapes, shapetype, mins, maxs = self.shapefile.info()
        self.numshapes = numshapes
        self.shapetype = shapelib_shapetypes[shapetype]

        # if there are shapes, set the bbox accordingly. Otherwise
        # set it to None.
        if self.numshapes:
            self.bbox = mins[:2] + maxs[:2]
        else:
            self.bbox = None

        # estimate a good depth for the quad tree. Each depth
        # multiplies the number of nodes by four, therefore we
        # basically take the base 4 logarithm of the number of
        # shapes.
        if self.numshapes < 4:
            maxdepth = 1
        else:
            maxdepth = int(ceil(log(self.numshapes / 4.0) / log(4)))

        self.shapetree = shptree.SHPTree(self.shapefile.cobject(), 2,
                                         maxdepth)
        # Set the classification to None if there is a classification
        # and the new shapestore doesn't have a table with a suitable
        # column, i.e one with the same name and type as before
        # FIXME: Maybe we should keep it the same if the type is
        # compatible enough such as FIELDTYPE_DOUBLE and FIELDTYPE_INT
        if self.__classification is not None:
            fieldname = self.__classification.GetField()
            fieldtype = self.__classification.GetFieldType()
            table = self.store.Table()
            if (fieldname is not None
                and (not table.HasColumn(fieldname)
                     or table.Column(fieldname).type != fieldtype)):
                self.SetClassification(None)
        self.changed(LAYER_CHANGED, self)

    def ShapeStore(self):
        return self.store

    def Destroy(self):
        BaseLayer.Destroy(self)
        self.SetClassification(None)

    def BoundingBox(self):
        """Return the layer's bounding box in the intrinsic coordinate system.

        If the layer has no shapes, return None.
        """
        return self.bbox

    def LatLongBoundingBox(self):
        """Return the layer's bounding box in lat/long coordinates.

        Return None, if the layer doesn't contain any shapes.
        """
        bbox = self.BoundingBox()
        if bbox is not None:
            llx, lly, urx, ury = bbox
            if self.projection is not None:
                llx, lly = self.projection.Inverse(llx, lly)
                urx, ury = self.projection.Inverse(urx, ury)
            return llx, lly, urx, ury
        else:
            return None

    def ShapesBoundingBox(self, shapes):
        """Return a bounding box in lat/long coordinates for the given
        list of shape ids.

        If shapes is None or empty, return None.
        """

        if shapes is None or len(shapes) == 0: return None

        llx = []
        lly = []
        urx = []
        ury = []

        if self.projection is not None:
            inverse = lambda x, y: self.projection.Inverse(x, y)
        else:
            inverse = lambda x, y: (x, y)

        for id in shapes:
            left, bottom, right, top = self.Shape(id).compute_bbox()

            left, bottom = inverse(left, bottom)
            right, top   = inverse(right, top)

            llx.append(left)
            lly.append(bottom)
            urx.append(right)
            ury.append(top)

        return (min(llx), min(lly), max(urx), max(ury))

    def GetFieldType(self, fieldName):
        if self.table.HasColumn(fieldName):
            return self.table.Column(fieldName).type
        return None

    def NumShapes(self):
        """Return the number of shapes in the layer"""
        return self.numshapes

    def ShapeType(self):
        """Return the type of the shapes in the layer.
        This is either SHAPETYPE_POINT, SHAPETYPE_ARC or SHAPETYPE_POLYGON.
        """
        return self.shapetype

    def Shape(self, index):
        """Return the shape with index index"""
        shape = self.shapefile.read_object(index)

        if self.shapetype == SHAPETYPE_POINT:
            points = shape.vertices()
        else:
            #for poly in shape.vertices():
            poly = shape.vertices()[0]
            points = []
            for x, y in poly:
                points.append((x, y))

        return Shape(points)

    def ShapesInRegion(self, box):
        """Return the ids of the shapes that overlap the box.

        Box is a tuple (left, bottom, right, top) in unprojected coordinates.
        """
        left, bottom, right, top = box

        if self.projection is not None:
            left,  bottom = self.projection.Forward(left, bottom)
            right, top    = self.projection.Forward(right, top)

        return self.shapetree.find_shapes((left, bottom), (right, top))

    def HasClassification(self):
        return True

    def GetClassification(self):
        return self.__classification

    def SetClassification(self, clazz):
        """Set the classification to 'clazz'

        If 'clazz' is None a default classification is created
        """

        # prevent infinite recursion when calling SetLayer()
        if self.__setClassLock: return

        self.__setClassLock = True

        if clazz is None:
            if self.__classification is not None:
                self.__classification.SetLayer(None)
            self.__classification = classification.Classification()
        else:
            self.__classification = clazz
            try:
                self.__classification.SetLayer(self)
            except ValueError:
                self.__setClassLock = False
                raise ValueError

        self.changed(LAYER_CHANGED, self)

        self.__setClassLock = False

    def ClassChanged(self):
        """Called from the classification object when it has changed."""
        self.changed(LAYER_CHANGED, self)
 
    def TreeInfo(self):
        items = []

        if hasattr(self, 'filename'):
            items.append(_("Filename: %s") % self.filename)

        if self.Visible():
            items.append(_("Shown"))
        else:
            items.append(_("Hidden"))
        items.append(_("Shapes: %d") % self.NumShapes())

        bbox = self.LatLongBoundingBox()
        if bbox is not None:
            items.append(_("Extent (lat-lon): (%g, %g, %g, %g)") % bbox)
        else:
            items.append(_("Extent (lat-lon):"))
        items.append(_("Shapetype: %s") % shapetype_names[self.ShapeType()])

        if self.projection and len(self.projection.params) > 0:
            items.append((_("Projection"),
                        [str(param) for param in self.projection.params]))

        items.append(self.__classification)

        return (_("Layer '%s'") % self.Title(), items)


class RasterLayer(BaseLayer):

    def __init__(self, title, filename, projection = None, visible = True):
        """Initialize the Raster Layer.

        title -- title for the layer.

        filename -- file name of the source image.

        projection -- Projection object describing the projection which
                      the source image is in.

        visible -- True is the layer should initially be visible.

        Throws IOError if the filename is invalid or points to a file that
        is not in a format GDAL can use.
        """

        BaseLayer.__init__(self, title, visible = visible)

        self.projection = projection
        self.filename = filename

        self.bbox = -1

        #
        # temporarily open the file so that GDAL can test if it's valid.
        #
        dataset = gdal.Open(self.filename, GA_ReadOnly)

        if dataset is None:
            raise IOError()

        self.UnsetModified()

    def BoundingBox(self):
        """Return the layer's bounding box in the intrinsic coordinate system.

        If the layer has no shapes, return None.
        """
        if self.bbox == -1:
            dataset = gdal.Open(self.filename, GA_ReadOnly)
            if dataset is None:
                self.bbox = None
            else:
                geotransform = dataset.GetGeoTransform()
                if geotransform is None:
                    return None

                x = 0
                y = dataset.RasterYSize
                left = geotransform[0] +        \
                       geotransform[1] * x +    \
                       geotransform[2] * y

                bottom = geotransform[3] +      \
                         geotransform[4] * x +  \
                         geotransform[5] * y

                x = dataset.RasterXSize
                y = 0
                right = geotransform[0] +       \
                        geotransform[1] * x +   \
                        geotransform[2] * y

                top = geotransform[3] +         \
                      geotransform[4] * x +     \
                      geotransform[5] * y

                self.bbox = (left, bottom, right, top)

        return self.bbox

    def LatLongBoundingBox(self):
        bbox = self.BoundingBox()
        if bbox is None:
            return None

        llx, lly, urx, ury = bbox
        if self.projection is not None:
            llx, lly = self.projection.Inverse(llx, lly)
            urx, ury = self.projection.Inverse(urx, ury)

        return llx, lly, urx, ury

    def GetImageFilename(self):
        return self.filename

    def TreeInfo(self):
        items = []

        if self.Visible():
            items.append(_("Shown"))
        else:
            items.append(_("Hidden"))
        items.append(_("Shapes: %d") % self.NumShapes())

        bbox = self.LatLongBoundingBox()
        if bbox is not None:
            items.append(_("Extent (lat-lon): (%g, %g, %g, %g)") % bbox)
        else:
            items.append(_("Extent (lat-lon):"))

        if self.projection and len(self.projection.params) > 0:
            items.append((_("Projection"),
                        [str(param) for param in self.projection.params]))

        return (_("Layer '%s'") % self.Title(), items)

1	bh	701	# Copyright (c) 2001, 2002, 2003 by Intevation GmbH
2	bh	6	# Authors:
3			# Bernhard Herzog <[email protected]>
4	jonathan	412	# Jonathan Coles <[email protected]>
5	bh	6	#
6			# This program is free software under the GPL (>=v2)
7			# Read the file COPYING coming with Thuban for details.
8
9			__version__ = "$Revision$"
10
11	bh	171	from math import log, ceil
12
13	jan	374	from Thuban import _
14
15	bh	143	import shapelib, shptree
16	bh	6
17	jonathan	929	import gdal
18			from gdalconst import GA_ReadOnly
19
20	bh	701	from messages import LAYER_PROJECTION_CHANGED, LAYER_VISIBILITY_CHANGED, \
21			LAYER_CHANGED
22	bh	6
23			from color import Color
24
25	jonathan	437	import classification
26	bh	6
27			from base import TitledObject, Modifiable
28
29	bh	723
30	bh	6	class Shape:
31
32			"""Represent one shape"""
33
34			def __init__(self, points):
35			self.points = points
36			#self.compute_bbox()
37	jonathan	828	self.bbox = None
38	bh	6
39			def compute_bbox(self):
40	jonathan	828	if self.bbox is not None:
41			return self.bbox
42
43	bh	6	xs = []
44			ys = []
45			for x, y in self.points:
46			xs.append(x)
47			ys.append(y)
48			self.llx = min(xs)
49			self.lly = min(ys)
50			self.urx = max(xs)
51			self.ury = max(ys)
52
53	jonathan	828	self.bbox = (self.llx, self.lly, self.urx, self.ury)
54
55			return self.bbox
56
57	bh	6	def Points(self):
58			return self.points
59
60
61
62			# Shape type constants
63			SHAPETYPE_POLYGON = "polygon"
64			SHAPETYPE_ARC = "arc"
65			SHAPETYPE_POINT = "point"
66
67			# mapping from shapelib shapetype constants to our constants
68			shapelib_shapetypes = {shapelib.SHPT_POLYGON: SHAPETYPE_POLYGON,
69			shapelib.SHPT_ARC: SHAPETYPE_ARC,
70			shapelib.SHPT_POINT: SHAPETYPE_POINT}
71
72			shapetype_names = {SHAPETYPE_POINT: "Point",
73			SHAPETYPE_ARC: "Arc",
74			SHAPETYPE_POLYGON: "Polygon"}
75
76			class BaseLayer(TitledObject, Modifiable):
77
78			"""Base class for the layers."""
79
80	jonathan	929	def __init__(self, title, visible = True, projection = None):
81	bh	6	"""Initialize the layer.
82
83			title -- the title
84			visible -- boolean. If true the layer is visible.
85			"""
86			TitledObject.__init__(self, title)
87			Modifiable.__init__(self)
88			self.visible = visible
89	jonathan	929	self.projection = projection
90	bh	6
91			def Visible(self):
92			"""Return true if layer is visible"""
93			return self.visible
94
95			def SetVisible(self, visible):
96			"""Set the layer's visibility."""
97			self.visible = visible
98			self.issue(LAYER_VISIBILITY_CHANGED, self)
99	bh	276
100	jonathan	929	def HasClassification(self):
101			"""Determine if this layer support classifications."""
102			return False
103	bh	276
104	jonathan	929	def GetProjection(self):
105			"""Return the layer's projection."""
106			return self.projection
107
108			def SetProjection(self, projection):
109			"""Set the layer's projection"""
110			self.projection = projection
111			self.changed(LAYER_PROJECTION_CHANGED, self)
112
113	bh	6	class Layer(BaseLayer):
114
115			"""Represent the information of one geodata file (currently a shapefile)
116
117			All children of the layer have the same type.
118
119			A layer has fill and stroke colors. Colors should be instances of
120			Color. They can also be None, indicating no fill or no stroke.
121
122			The layer objects send the following events, all of which have the
123			layer object as parameter:
124
125			TITLE_CHANGED -- The title has changed.
126			LAYER_PROJECTION_CHANGED -- the projection has changed.
127			"""
128
129	bh	723	def __init__(self, title, data, projection = None,
130	jonathan	610	fill = Color.Transparent,
131	jonathan	412	stroke = Color.Black,
132	jonathan	464	lineWidth = 1,
133	jonathan	771	visible = True):
134	bh	6	"""Initialize the layer.
135
136			title -- the title
137	bh	723	data -- datastore object for the shape data shown by the layer
138	bh	6	projection -- the projection object. Its Inverse method is
139			assumed to map the layer's coordinates to lat/long
140			coordinates
141	jonathan	610	fill -- the fill color or Color.Transparent if the shapes are
142			not filled
143			stroke -- the stroke color or Color.Transparent if the shapes
144			are not stroked
145	bh	6	visible -- boolean. If true the layer is visible.
146
147			colors are expected to be instances of Color class
148			"""
149	jonathan	929	BaseLayer.__init__(self, title,
150			visible = visible,
151			projection = projection)
152	bh	276
153	jonathan	481	#
154			# this is really important so that when the classification class
155			# tries to set its parent layer the variable will exist
156			#
157	bh	723	self.__classification = None
158	jonathan	529	self.__setClassLock = False
159	jonathan	481
160	bh	723	self.SetShapeStore(data)
161	jonathan	492
162			self.SetClassification(None)
163
164	jonathan	464	self.__classification.SetDefaultLineColor(stroke)
165			self.__classification.SetDefaultLineWidth(lineWidth)
166	jonathan	412	self.__classification.SetDefaultFill(fill)
167	jonathan	492	self.__classification.SetLayer(self)
168	jonathan	364
169	jonathan	389	self.UnsetModified()
170
171	bh	6
172	bh	723	def SetShapeStore(self, store):
173			self.store = store
174			self.shapefile = self.store.Shapefile()
175			self.shapetable = self.store.Table()
176	bh	996	if hasattr(self.store, "FileName"):
177			self.filename = self.store.FileName()
178	bh	723	self.table = self.shapetable
179	bh	179
180	bh	723	numshapes, shapetype, mins, maxs = self.shapefile.info()
181			self.numshapes = numshapes
182			self.shapetype = shapelib_shapetypes[shapetype]
183	bh	171
184	bh	723	# if there are shapes, set the bbox accordingly. Otherwise
185			# set it to None.
186			if self.numshapes:
187			self.bbox = mins[:2] + maxs[:2]
188			else:
189			self.bbox = None
190	bh	171
191	bh	723	# estimate a good depth for the quad tree. Each depth
192			# multiplies the number of nodes by four, therefore we
193			# basically take the base 4 logarithm of the number of
194			# shapes.
195			if self.numshapes < 4:
196			maxdepth = 1
197			else:
198			maxdepth = int(ceil(log(self.numshapes / 4.0) / log(4)))
199
200			self.shapetree = shptree.SHPTree(self.shapefile.cobject(), 2,
201			maxdepth)
202	bh	1088	# Set the classification to None if there is a classification
203			# and the new shapestore doesn't have a table with a suitable
204			# column, i.e one with the same name and type as before
205			# FIXME: Maybe we should keep it the same if the type is
206			# compatible enough such as FIELDTYPE_DOUBLE and FIELDTYPE_INT
207	bh	723	if self.__classification is not None:
208			fieldname = self.__classification.GetField()
209	bh	1088	fieldtype = self.__classification.GetFieldType()
210			table = self.store.Table()
211			if (fieldname is not None
212			and (not table.HasColumn(fieldname)
213			or table.Column(fieldname).type != fieldtype)):
214	bh	723	self.SetClassification(None)
215			self.changed(LAYER_CHANGED, self)
216
217			def ShapeStore(self):
218			return self.store
219
220	bh	258	def Destroy(self):
221	bh	260	BaseLayer.Destroy(self)
222	jonathan	529	self.SetClassification(None)
223	bh	258
224	bh	6	def BoundingBox(self):
225	bh	179	"""Return the layer's bounding box in the intrinsic coordinate system.
226
227			If the layer has no shapes, return None.
228			"""
229	bh	6	return self.bbox
230
231			def LatLongBoundingBox(self):
232	bh	179	"""Return the layer's bounding box in lat/long coordinates.
233	bh	6
234	bh	179	Return None, if the layer doesn't contain any shapes.
235			"""
236			bbox = self.BoundingBox()
237			if bbox is not None:
238			llx, lly, urx, ury = bbox
239			if self.projection is not None:
240			llx, lly = self.projection.Inverse(llx, lly)
241			urx, ury = self.projection.Inverse(urx, ury)
242			return llx, lly, urx, ury
243			else:
244			return None
245
246	jonathan	828	def ShapesBoundingBox(self, shapes):
247			"""Return a bounding box in lat/long coordinates for the given
248			list of shape ids.
249
250			If shapes is None or empty, return None.
251			"""
252
253			if shapes is None or len(shapes) == 0: return None
254
255			llx = []
256			lly = []
257			urx = []
258			ury = []
259
260			if self.projection is not None:
261			inverse = lambda x, y: self.projection.Inverse(x, y)
262			else:
263			inverse = lambda x, y: (x, y)
264
265			for id in shapes:
266			left, bottom, right, top = self.Shape(id).compute_bbox()
267
268			left, bottom = inverse(left, bottom)
269			right, top = inverse(right, top)
270
271			llx.append(left)
272			lly.append(bottom)
273			urx.append(right)
274			ury.append(top)
275
276			return (min(llx), min(lly), max(urx), max(ury))
277
278	jonathan	464	def GetFieldType(self, fieldName):
279	bh	839	if self.table.HasColumn(fieldName):
280			return self.table.Column(fieldName).type
281			return None
282	jonathan	464
283	bh	6	def NumShapes(self):
284			"""Return the number of shapes in the layer"""
285			return self.numshapes
286
287			def ShapeType(self):
288			"""Return the type of the shapes in the layer.
289			This is either SHAPETYPE_POINT, SHAPETYPE_ARC or SHAPETYPE_POLYGON.
290			"""
291			return self.shapetype
292
293			def Shape(self, index):
294			"""Return the shape with index index"""
295			shape = self.shapefile.read_object(index)
296	jonathan	364
297	bh	6	if self.shapetype == SHAPETYPE_POINT:
298			points = shape.vertices()
299			else:
300			#for poly in shape.vertices():
301			poly = shape.vertices()[0]
302			points = []
303			for x, y in poly:
304	bh	82	points.append((x, y))
305	jonathan	364
306	bh	6	return Shape(points)
307
308	bh	143	def ShapesInRegion(self, box):
309			"""Return the ids of the shapes that overlap the box.
310
311	jonathan	794	Box is a tuple (left, bottom, right, top) in unprojected coordinates.
312	bh	143	"""
313			left, bottom, right, top = box
314	jonathan	794
315			if self.projection is not None:
316			left, bottom = self.projection.Forward(left, bottom)
317			right, top = self.projection.Forward(right, top)
318
319	bh	147	return self.shapetree.find_shapes((left, bottom), (right, top))
320	bh	143
321	jonathan	929	def HasClassification(self):
322			return True
323	jonathan	725
324	jonathan	412	def GetClassification(self):
325			return self.__classification
326
327			def SetClassification(self, clazz):
328	jonathan	492	"""Set the classification to 'clazz'
329	jonathan	481
330	jonathan	492	If 'clazz' is None a default classification is created
331			"""
332	jonathan	481
333	jonathan	529	# prevent infinite recursion when calling SetLayer()
334			if self.__setClassLock: return
335
336			self.__setClassLock = True
337
338	jonathan	492	if clazz is None:
339	jonathan	529	if self.__classification is not None:
340			self.__classification.SetLayer(None)
341	jonathan	492	self.__classification = classification.Classification()
342			else:
343			self.__classification = clazz
344	jonathan	529	try:
345			self.__classification.SetLayer(self)
346			except ValueError:
347			self.__setClassLock = False
348			raise ValueError
349	jonathan	492
350	jonathan	545	self.changed(LAYER_CHANGED, self)
351	jonathan	412
352	jonathan	529	self.__setClassLock = False
353
354	jonathan	492	def ClassChanged(self):
355			"""Called from the classification object when it has changed."""
356	jonathan	558	self.changed(LAYER_CHANGED, self)
357	jonathan	492
358	bh	217	def TreeInfo(self):
359			items = []
360
361	jan	1086	if hasattr(self, 'filename'):
362			items.append(_("Filename: %s") % self.filename)
363	jan	1012
364	bh	217	if self.Visible():
365	jan	374	items.append(_("Shown"))
366	bh	217	else:
367	jan	374	items.append(_("Hidden"))
368			items.append(_("Shapes: %d") % self.NumShapes())
369	bh	217
370			bbox = self.LatLongBoundingBox()
371			if bbox is not None:
372	jan	374	items.append(_("Extent (lat-lon): (%g, %g, %g, %g)") % bbox)
373	bh	217	else:
374	jan	374	items.append(_("Extent (lat-lon):"))
375			items.append(_("Shapetype: %s") % shapetype_names[self.ShapeType()])
376	bh	217
377	jonathan	736	if self.projection and len(self.projection.params) > 0:
378			items.append((_("Projection"),
379			[str(param) for param in self.projection.params]))
380
381	jonathan	412	items.append(self.__classification)
382	bh	217
383	jan	374	return (_("Layer '%s'") % self.Title(), items)
384	jonathan	382
385	jonathan	736
386	jonathan	929	class RasterLayer(BaseLayer):
387
388			def __init__(self, title, filename, projection = None, visible = True):
389			"""Initialize the Raster Layer.
390
391			title -- title for the layer.
392
393			filename -- file name of the source image.
394
395			projection -- Projection object describing the projection which
396			the source image is in.
397
398			visible -- True is the layer should initially be visible.
399	jonathan	961
400			Throws IOError if the filename is invalid or points to a file that
401			is not in a format GDAL can use.
402	jonathan	929	"""
403
404			BaseLayer.__init__(self, title, visible = visible)
405
406			self.projection = projection
407			self.filename = filename
408
409			self.bbox = -1
410
411	jonathan	961	#
412			# temporarily open the file so that GDAL can test if it's valid.
413			#
414			dataset = gdal.Open(self.filename, GA_ReadOnly)
415
416			if dataset is None:
417			raise IOError()
418
419	jonathan	929	self.UnsetModified()
420
421			def BoundingBox(self):
422			"""Return the layer's bounding box in the intrinsic coordinate system.
423
424			If the layer has no shapes, return None.
425			"""
426			if self.bbox == -1:
427			dataset = gdal.Open(self.filename, GA_ReadOnly)
428			if dataset is None:
429			self.bbox = None
430			else:
431	jonathan	961	geotransform = dataset.GetGeoTransform()
432			if geotransform is None:
433			return None
434
435			x = 0
436			y = dataset.RasterYSize
437			left = geotransform[0] + \
438			geotransform[1] * x + \
439			geotransform[2] * y
440
441			bottom = geotransform[3] + \
442			geotransform[4] * x + \
443			geotransform[5] * y
444
445			x = dataset.RasterXSize
446			y = 0
447			right = geotransform[0] + \
448			geotransform[1] * x + \
449			geotransform[2] * y
450
451			top = geotransform[3] + \
452			geotransform[4] * x + \
453			geotransform[5] * y
454
455	jonathan	929	self.bbox = (left, bottom, right, top)
456
457			return self.bbox
458
459			def LatLongBoundingBox(self):
460			bbox = self.BoundingBox()
461	jonathan	961	if bbox is None:
462	jonathan	929	return None
463
464	jonathan	961	llx, lly, urx, ury = bbox
465			if self.projection is not None:
466			llx, lly = self.projection.Inverse(llx, lly)
467			urx, ury = self.projection.Inverse(urx, ury)
468
469			return llx, lly, urx, ury
470
471	jonathan	929	def GetImageFilename(self):
472			return self.filename
473
474			def TreeInfo(self):
475			items = []
476
477			if self.Visible():
478			items.append(_("Shown"))
479			else:
480			items.append(_("Hidden"))
481			items.append(_("Shapes: %d") % self.NumShapes())
482
483			bbox = self.LatLongBoundingBox()
484			if bbox is not None:
485			items.append(_("Extent (lat-lon): (%g, %g, %g, %g)") % bbox)
486			else:
487			items.append(_("Extent (lat-lon):"))
488
489			if self.projection and len(self.projection.params) > 0:
490			items.append((_("Projection"),
491			[str(param) for param in self.projection.params]))
492
493			return (_("Layer '%s'") % self.Title(), items)
494
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