/[thuban]/trunk/thuban/Thuban/Model/layer.py
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revision 481 by jonathan, Thu Mar 6 16:46:36 2003 UTC revision 1117 by bh, Fri May 30 18:31:19 2003 UTC
# Line 1  Line 1 
1  # Copyright (c) 2001, 2002 by Intevation GmbH  # Copyright (c) 2001, 2002, 2003 by Intevation GmbH
2  # Authors:  # Authors:
3  # Bernhard Herzog <[email protected]>  # Bernhard Herzog <[email protected]>
4  # Jonathan Coles <[email protected]>  # Jonathan Coles <[email protected]>
# Line 8  Line 8 
8    
9  __version__ = "$Revision$"  __version__ = "$Revision$"
10    
 import os  
11  from math import log, ceil  from math import log, ceil
12    
13  from Thuban import _  from Thuban import _
14    
15  import shapelib, shptree  import shapelib, shptree
16    
17  from messages import LAYER_PROJECTION_CHANGED, LAYER_LEGEND_CHANGED, \  import gdal
18       LAYER_VISIBILITY_CHANGED  from gdalconst import GA_ReadOnly
19    
20    from messages import LAYER_PROJECTION_CHANGED, LAYER_VISIBILITY_CHANGED, \
21         LAYER_CHANGED
22    
23  from color import Color  from color import Color
24    
25  import classification  import classification
26    
 from table import Table  
   
27  from base import TitledObject, Modifiable  from base import TitledObject, Modifiable
28    
29    
30  class Shape:  class Shape:
31    
32      """Represent one shape"""      """Represent one shape"""
# Line 33  class Shape: Line 34  class Shape:
34      def __init__(self, points):      def __init__(self, points):
35          self.points = points          self.points = points
36          #self.compute_bbox()          #self.compute_bbox()
37            self.bbox = None
38    
39      def compute_bbox(self):      def compute_bbox(self):
40            if self.bbox is not None:
41                return self.bbox
42    
43          xs = []          xs = []
44          ys = []          ys = []
45          for x, y in self.points:          for x, y in self.points:
# Line 45  class Shape: Line 50  class Shape:
50          self.urx = max(xs)          self.urx = max(xs)
51          self.ury = max(ys)          self.ury = max(ys)
52    
53            self.bbox = (self.llx, self.lly, self.urx, self.ury)
54    
55            return self.bbox
56    
57      def Points(self):      def Points(self):
58          return self.points          return self.points
59    
# Line 68  class BaseLayer(TitledObject, Modifiable Line 77  class BaseLayer(TitledObject, Modifiable
77    
78      """Base class for the layers."""      """Base class for the layers."""
79    
80      def __init__(self, title, visible = 1):      def __init__(self, title, visible = True, projection = None):
81          """Initialize the layer.          """Initialize the layer.
82    
83          title -- the title          title -- the title
# Line 77  class BaseLayer(TitledObject, Modifiable Line 86  class BaseLayer(TitledObject, Modifiable
86          TitledObject.__init__(self, title)          TitledObject.__init__(self, title)
87          Modifiable.__init__(self)          Modifiable.__init__(self)
88          self.visible = visible          self.visible = visible
89            self.projection = projection
90    
91      def Visible(self):      def Visible(self):
92          """Return true if layer is visible"""          """Return true if layer is visible"""
# Line 87  class BaseLayer(TitledObject, Modifiable Line 97  class BaseLayer(TitledObject, Modifiable
97          self.visible = visible          self.visible = visible
98          self.issue(LAYER_VISIBILITY_CHANGED, self)          self.issue(LAYER_VISIBILITY_CHANGED, self)
99    
100        def HasClassification(self):
101            """Determine if this layer support classifications."""
102            return False
103    
104        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  class Layer(BaseLayer):  class Layer(BaseLayer):
114    
# Line 102  class Layer(BaseLayer): Line 124  class Layer(BaseLayer):
124    
125          TITLE_CHANGED -- The title has changed.          TITLE_CHANGED -- The title has changed.
126          LAYER_PROJECTION_CHANGED -- the projection has changed.          LAYER_PROJECTION_CHANGED -- the projection has changed.
         LAYER_LEGEND_CHANGED -- the fill or stroke attributes have changed  
   
127      """      """
128    
129      def __init__(self, title, filename, projection = None,      def __init__(self, title, data, projection = None,
130                   fill = Color.None,                   fill = Color.Transparent,
131                   stroke = Color.Black,                   stroke = Color.Black,
132                   lineWidth = 1,                   lineWidth = 1,
133                   visible = 1):                   visible = True):
134          """Initialize the layer.          """Initialize the layer.
135    
136          title -- the title          title -- the title
137          filename -- the name of the shapefile          data -- datastore object for the shape data shown by the layer
138          projection -- the projection object. Its Inverse method is          projection -- the projection object. Its Inverse method is
139                 assumed to map the layer's coordinates to lat/long                 assumed to map the layer's coordinates to lat/long
140                 coordinates                 coordinates
141          fill -- the fill color or Color.None if the shapes are not filled          fill -- the fill color or Color.Transparent if the shapes are
142          stroke -- the stroke color or Color.None if the shapes are not stroked                  not filled
143            stroke -- the stroke color or Color.Transparent if the shapes
144                    are not stroked
145          visible -- boolean. If true the layer is visible.          visible -- boolean. If true the layer is visible.
146    
147          colors are expected to be instances of Color class          colors are expected to be instances of Color class
148          """          """
149          BaseLayer.__init__(self, title, visible = visible)          BaseLayer.__init__(self, title,
150                                     visible = visible,
151          # Make the filename absolute. The filename will be                                   projection = projection)
         # interpreted relative to that anyway, but when saving a  
         # session we need to compare absolute paths and it's usually  
         # safer to always work with absolute paths.  
         self.filename = os.path.abspath(filename)  
   
         self.projection = projection  
         self.shapefile = None  
         self.shapetree = None  
         self.open_shapefile()  
         # shapetable is the table associated with the shapefile, while  
         # table is the default table used to look up attributes for  
         # display  
         self.shapetable = Table(filename)  
         self.table = self.shapetable  
152    
153          #          #
154          # this is really important so that when the classification class          # this is really important so that when the classification class
155          # tries to set its parent layer the variable will exist          # tries to set its parent layer the variable will exist
156          #          #
157          self.__classification = None          self.__classification = None
158            self.__setClassLock = False
159    
160            self.SetShapeStore(data)
161    
162            self.SetClassification(None)
163    
         self.SetClassification(classification.Classification(self))  
164          self.__classification.SetDefaultLineColor(stroke)          self.__classification.SetDefaultLineColor(stroke)
165          self.__classification.SetDefaultLineWidth(lineWidth)          self.__classification.SetDefaultLineWidth(lineWidth)
166          self.__classification.SetDefaultFill(fill)          self.__classification.SetDefaultFill(fill)
167            self.__classification.SetLayer(self)
168    
169          self.UnsetModified()          self.UnsetModified()
170    
     def open_shapefile(self):  
         if self.shapefile is None:  
             self.shapefile = shapelib.ShapeFile(self.filename)  
             numshapes, shapetype, mins, maxs = self.shapefile.info()  
             self.numshapes = numshapes  
             self.shapetype = shapelib_shapetypes[shapetype]  
   
             # if there are shapes, set the bbox accordinly. Otherwise  
             # set it to None.  
             if self.numshapes:  
                 self.bbox = mins[:2] + maxs[:2]  
             else:  
                 self.bbox = None  
171    
172              # estimate a good depth for the quad tree. Each depth      def SetShapeStore(self, store):
173              # multiplies the number of nodes by four, therefore we          self.store = store
174              # basically take the base 4 logarithm of the number of          self.shapefile = self.store.Shapefile()
175              # shapes.          self.shapetable = self.store.Table()
176              if self.numshapes < 4:          if hasattr(self.store, "FileName"):
177                  maxdepth = 1              self.filename = self.store.FileName()
178              else:          self.table = self.shapetable
179                  maxdepth = int(ceil(log(self.numshapes / 4.0) / log(4)))  
180            numshapes, shapetype, mins, maxs = self.shapefile.info()
181            self.numshapes = numshapes
182            self.shapetype = shapelib_shapetypes[shapetype]
183    
184            # 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    
191              self.shapetree = shptree.SHPTree(self.shapefile.cobject(), 2,          # estimate a good depth for the quad tree. Each depth
192                                               maxdepth)          # 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            # 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            if self.__classification is not None:
208                fieldname = self.__classification.GetField()
209                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                    self.SetClassification(None)
215            self.changed(LAYER_CHANGED, self)
216    
217        def ShapeStore(self):
218            return self.store
219    
220      def Destroy(self):      def Destroy(self):
221          BaseLayer.Destroy(self)          BaseLayer.Destroy(self)
222          if self.shapefile is not None:          self.SetClassification(None)
223              self.shapefile.close()          self.store = self.shapetree = None
224              self.shapefile = None          self.table = self.shapefile = self.shapetable = None
             self.shapetree = None  
         self.table.Destroy()  
225    
226      def BoundingBox(self):      def BoundingBox(self):
227          """Return the layer's bounding box in the intrinsic coordinate system.          """Return the layer's bounding box in the intrinsic coordinate system.
228    
229          If the layer has no shapes, return None.          If the layer has no shapes, return None.
230          """          """
         # The bbox will be set by open_shapefile just as we need it  
         # here.  
         self.open_shapefile()  
231          return self.bbox          return self.bbox
232    
233      def LatLongBoundingBox(self):      def LatLongBoundingBox(self):
# Line 214  class Layer(BaseLayer): Line 245  class Layer(BaseLayer):
245          else:          else:
246              return None              return None
247    
248      def GetFieldType(self, fieldName):      def ShapesBoundingBox(self, shapes):
249          self.open_shapefile()          """Return a bounding box in lat/long coordinates for the given
250          info = self.table.field_info_by_name(fieldName)          list of shape ids.
251          if info is not None:  
252              return info[0]          If shapes is None or empty, return None.
253            """
254    
255            if shapes is None or len(shapes) == 0: return None
256    
257            llx = []
258            lly = []
259            urx = []
260            ury = []
261    
262            if self.projection is not None:
263                inverse = lambda x, y: self.projection.Inverse(x, y)
264          else:          else:
265              return None              inverse = lambda x, y: (x, y)
266    
267            for id in shapes:
268                left, bottom, right, top = self.Shape(id).compute_bbox()
269    
270                left, bottom = inverse(left, bottom)
271                right, top   = inverse(right, top)
272    
273                llx.append(left)
274                lly.append(bottom)
275                urx.append(right)
276                ury.append(top)
277    
278            return (min(llx), min(lly), max(urx), max(ury))
279    
280        def GetFieldType(self, fieldName):
281            if self.table.HasColumn(fieldName):
282                return self.table.Column(fieldName).type
283            return None
284    
285      def NumShapes(self):      def NumShapes(self):
286          """Return the number of shapes in the layer"""          """Return the number of shapes in the layer"""
         self.open_shapefile()  
287          return self.numshapes          return self.numshapes
288    
289      def ShapeType(self):      def ShapeType(self):
290          """Return the type of the shapes in the layer.          """Return the type of the shapes in the layer.
291          This is either SHAPETYPE_POINT, SHAPETYPE_ARC or SHAPETYPE_POLYGON.          This is either SHAPETYPE_POINT, SHAPETYPE_ARC or SHAPETYPE_POLYGON.
292          """          """
         self.open_shapefile()  
293          return self.shapetype          return self.shapetype
294    
295      def Shape(self, index):      def Shape(self, index):
296          """Return the shape with index index"""          """Return the shape with index index"""
         self.open_shapefile()  
297          shape = self.shapefile.read_object(index)          shape = self.shapefile.read_object(index)
298    
299          if self.shapetype == SHAPETYPE_POINT:          if self.shapetype == SHAPETYPE_POINT:
# Line 253  class Layer(BaseLayer): Line 310  class Layer(BaseLayer):
310      def ShapesInRegion(self, box):      def ShapesInRegion(self, box):
311          """Return the ids of the shapes that overlap the box.          """Return the ids of the shapes that overlap the box.
312    
313          Box is a tuple (left, bottom, right, top) in the coordinate          Box is a tuple (left, bottom, right, top) in unprojected coordinates.
         system used by the layer's shapefile.  
314          """          """
315          left, bottom, right, top = box          left, bottom, right, top = box
316    
317            if self.projection is not None:
318                left,  bottom = self.projection.Forward(left, bottom)
319                right, top    = self.projection.Forward(right, top)
320    
321          return self.shapetree.find_shapes((left, bottom), (right, top))          return self.shapetree.find_shapes((left, bottom), (right, top))
322    
323      def SetProjection(self, projection):      def HasClassification(self):
324          """Set the layer's projection"""          return True
         self.projection = projection  
         self.changed(LAYER_PROJECTION_CHANGED, self)  
325    
326      def GetClassification(self):      def GetClassification(self):
327          return self.__classification          return self.__classification
328    
329      def SetClassification(self, clazz):      def SetClassification(self, clazz):
330            """Set the classification to 'clazz'
331    
332            If 'clazz' is None a default classification is created
333            """
334    
335          # prevent infinite recursion when calling SetLayer()          # prevent infinite recursion when calling SetLayer()
336          if clazz == self.__classification:          if self.__setClassLock: return
             return  
337    
338          self.__classification = clazz          self.__setClassLock = True
         self.__classification.SetLayer(self)  
         self.changed(LAYER_LEGEND_CHANGED, self)  
339    
340            if clazz is None:
341                if self.__classification is not None:
342                    self.__classification.SetLayer(None)
343                self.__classification = classification.Classification()
344            else:
345                self.__classification = clazz
346                try:
347                    self.__classification.SetLayer(self)
348                except ValueError:
349                    self.__setClassLock = False
350                    raise ValueError
351    
352            self.changed(LAYER_CHANGED, self)
353    
354            self.__setClassLock = False
355    
356        def ClassChanged(self):
357            """Called from the classification object when it has changed."""
358            self.changed(LAYER_CHANGED, self)
359    
360      def TreeInfo(self):      def TreeInfo(self):
361          items = []          items = []
362    
363            if hasattr(self, 'filename'):
364                items.append(_("Filename: %s") % self.filename)
365    
366          if self.Visible():          if self.Visible():
367              items.append(_("Shown"))              items.append(_("Shown"))
368          else:          else:
# Line 293  class Layer(BaseLayer): Line 376  class Layer(BaseLayer):
376              items.append(_("Extent (lat-lon):"))              items.append(_("Extent (lat-lon):"))
377          items.append(_("Shapetype: %s") % shapetype_names[self.ShapeType()])          items.append(_("Shapetype: %s") % shapetype_names[self.ShapeType()])
378    
379            if self.projection and len(self.projection.params) > 0:
380                items.append((_("Projection"),
381                            [str(param) for param in self.projection.params]))
382    
383          items.append(self.__classification)          items.append(self.__classification)
384    
385          return (_("Layer '%s'") % self.Title(), items)          return (_("Layer '%s'") % self.Title(), items)
386    
387    
388    class RasterLayer(BaseLayer):
389    
390        def __init__(self, title, filename, projection = None, visible = True):
391            """Initialize the Raster Layer.
392    
393            title -- title for the layer.
394    
395            filename -- file name of the source image.
396    
397            projection -- Projection object describing the projection which
398                          the source image is in.
399    
400            visible -- True is the layer should initially be visible.
401    
402            Throws IOError if the filename is invalid or points to a file that
403            is not in a format GDAL can use.
404            """
405    
406            BaseLayer.__init__(self, title, visible = visible)
407    
408            self.projection = projection
409            self.filename = filename
410    
411            self.bbox = -1
412    
413            #
414            # temporarily open the file so that GDAL can test if it's valid.
415            #
416            dataset = gdal.Open(self.filename, GA_ReadOnly)
417    
418            if dataset is None:
419                raise IOError()
420    
421            self.UnsetModified()
422    
423        def BoundingBox(self):
424            """Return the layer's bounding box in the intrinsic coordinate system.
425    
426            If the layer has no shapes, return None.
427            """
428            if self.bbox == -1:
429                dataset = gdal.Open(self.filename, GA_ReadOnly)
430                if dataset is None:
431                    self.bbox = None
432                else:
433                    geotransform = dataset.GetGeoTransform()
434                    if geotransform is None:
435                        return None
436    
437                    x = 0
438                    y = dataset.RasterYSize
439                    left = geotransform[0] +        \
440                           geotransform[1] * x +    \
441                           geotransform[2] * y
442    
443                    bottom = geotransform[3] +      \
444                             geotransform[4] * x +  \
445                             geotransform[5] * y
446    
447                    x = dataset.RasterXSize
448                    y = 0
449                    right = geotransform[0] +       \
450                            geotransform[1] * x +   \
451                            geotransform[2] * y
452    
453                    top = geotransform[3] +         \
454                          geotransform[4] * x +     \
455                          geotransform[5] * y
456    
457                    self.bbox = (left, bottom, right, top)
458    
459            return self.bbox
460    
461        def LatLongBoundingBox(self):
462            bbox = self.BoundingBox()
463            if bbox is None:
464                return None
465    
466            llx, lly, urx, ury = bbox
467            if self.projection is not None:
468                llx, lly = self.projection.Inverse(llx, lly)
469                urx, ury = self.projection.Inverse(urx, ury)
470    
471            return llx, lly, urx, ury
472    
473        def GetImageFilename(self):
474            return self.filename
475    
476        def TreeInfo(self):
477            items = []
478    
479            if self.Visible():
480                items.append(_("Shown"))
481            else:
482                items.append(_("Hidden"))
483            items.append(_("Shapes: %d") % self.NumShapes())
484    
485            bbox = self.LatLongBoundingBox()
486            if bbox is not None:
487                items.append(_("Extent (lat-lon): (%g, %g, %g, %g)") % bbox)
488            else:
489                items.append(_("Extent (lat-lon):"))
490    
491            if self.projection and len(self.projection.params) > 0:
492                items.append((_("Projection"),
493                            [str(param) for param in self.projection.params]))
494    
495            return (_("Layer '%s'") % self.Title(), items)
496    
Legend:
Removed from v.481  
changed lines
  Added in v.1117
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