jonathan: thuban/Thuban/UI baserenderer.py, 1.17, 1.18 renderer.py, 1.57, 1.58

[cvs@intevation.de]

Author: jonathan

Update of /thubanrepository/thuban/Thuban/UI
In directory doto:/tmp/cvs-serv11859/Thuban/UI

Modified Files:
	baserenderer.py renderer.py 
Log Message:
Refactored baserenderer.py and renderer.py to remove baserenderer.py's
dependencies on wxPython. Added a new method projected_raster_layer()
that returns a raster layer image in projected space. This must be
implemented in classes derived from BaseRenderer. This also eliminates
the dependency on gdal in baserenderer.py.


Index: baserenderer.py
===================================================================
RCS file: /thubanrepository/thuban/Thuban/UI/baserenderer.py,v
retrieving revision 1.17
retrieving revision 1.18
diff -u -d -r1.17 -r1.18
--- baserenderer.py	16 Feb 2005 21:14:47 -0000	1.17
+++ baserenderer.py	18 Feb 2005 14:54:17 -0000	1.18
@@ -30,8 +30,6 @@
 
 import Thuban.Model.resource
 
-if Thuban.Model.resource.has_gdal_support():
-    from gdalwarp import ProjectRasterFile
 
 
 #
@@ -192,8 +190,7 @@
                 if isinstance(layer, Layer):
                     for i in self.draw_shape_layer_incrementally(layer):
                         yield True
-                elif isinstance(layer, RasterLayer) \
-                    and Thuban.Model.resource.has_gdal_support():
+                elif isinstance(layer, RasterLayer):
                     self.draw_raster_layer(layer)
                     yield True
                 else:
@@ -443,10 +440,10 @@
     def draw_raster_layer(self, layer):
         """Draw the raster layer
 
-        This implementation does the projection and scaling of the data
-        as required by the layer's and map's projections and the scale
-        and offset of the renderer and then hands the transformed data
-        to self.draw_raster_data() which has to be implemented in
+        This implementation uses self.projected_raster_layer() to project 
+        and scale the data as required by the layer's and map's projections 
+        and the scale and offset of the renderer and then hands the transformed 
+        data to self.draw_raster_data() which has to be implemented in
         derived classes.
         """
         offx, offy = self.offset
@@ -483,24 +480,47 @@
         width  = int(min(width,  round(fmax[0] - fmin[0] + 1)))
         height = int(min(height, round(fmax[1] - fmin[1] + 1)))
 
-        try:
-            options = 0
-            options = options | layer.MaskType()
-
-            project_params = (layer.GetImageFilename(), in_proj, out_proj, 
-                              (xmin, ymin, xmax, ymax), "", (width, height),
-                              options)
+        options = 0
+        options = options | layer.MaskType()
 
-            data = (width, height, apply(ProjectRasterFile, project_params))
+        img_data = self.projected_raster_layer(layer, in_proj, out_proj, 
+                    (xmin,ymin,xmax,ymax), [0,0], (width, height), options)
 
-        except (MemoryError, IOError, AttributeError, ValueError):
-            # Why does this catch AttributeError and ValueError?
-            # FIXME: The exception should be communicated to the user
-            # better.
-            traceback.print_exc()
-        else:
+        if img_data is not None:
+            data = (width, height, img_data)
             self.draw_raster_data(fmin[0]+offx, offy-fmax[1], data, "RAW")
             data = None
+
+    def projected_raster_layer(self, layer, srcProj, dstProj, extents,
+                               resolution, dimensions, options):
+        """Return the projected raster image associated with the layer.
+
+        The returned value will be a tuple of the form
+
+            (image_data, mask_data, alpha_data)
+
+        suitable for the data parameter to draw_raster_data.
+
+        The return value may be None if raster projections are not supported.
+
+        srcProj     --  a string describing the source projection
+        dstProj     --  a string describing the destination projection
+        extents     --  a tuple of the region to project in map coordinates
+        resolution  --  (currently not used, defaults to [0,0])
+        dimensions  --  a tuple (width, height) for the output image
+        options     --  bit-wise options to pass to the renderer
+
+        the currently supported values for options are
+
+            OPTS_MASK        = 1  -- generate a mask
+            OPTS_ALPHA       = 2  -- generate an alpha channel
+            OPTS_INVERT_MASK = 4  -- invert the values in the mask 
+                                     (if generated)
+
+        This method has to be implemented by derived classes.
+        """
+
+        raise NotImplementedError
 
     def draw_raster_data(self, x, y, data, format="BMP"):
         """Draw the raster image in data onto the DC with the top

Index: renderer.py
===================================================================
RCS file: /thubanrepository/thuban/Thuban/UI/renderer.py,v
retrieving revision 1.57
retrieving revision 1.58
diff -u -d -r1.57 -r1.58
--- renderer.py	16 Feb 2005 21:14:47 -0000	1.57
+++ renderer.py	18 Feb 2005 14:54:17 -0000	1.58
@@ -45,6 +45,9 @@
 
 from Thuban.version import versions
 
+if Thuban.Model.resource.has_gdal_support():
+    from gdalwarp import ProjectRasterFile
+
 
 # Map the strings used for the format parameter of the draw_raster_data
 # method to the appropriate wxWindows constants
@@ -107,6 +110,30 @@
     def label_font(self):
         return wxFont(int(round(self.resolution * 10)), wxSWISS, wxNORMAL,
                       wxNORMAL)
+
+    def projected_raster_layer(self, layer, srcProj, dstProj, extents,
+                               resolution, dimensions, options):
+
+        ret = None
+
+        if Thuban.Model.resource.has_gdal_support():
+
+            if versions['wxPython-tuple'] < (2,5,3):
+                options = options | 4  # INVERT_MASK_BITS
+                options = options & ~2 # ALPHA_MASK not supported
+
+            try:
+                ret = ProjectRasterFile(layer.GetImageFilename(), 
+                                        srcProj, dstProj,
+                                        extents, resolution, dimensions, 
+                                        options)
+            except (MemoryError, IOError, AttributeError, ValueError):
+                # Why does this catch AttributeError and ValueError?
+                # FIXME: The exception should be communicated to the user
+                # better.
+                traceback.print_exc()
+
+        return ret
 
     def draw_raster_data(self, x,y, data, format = 'BMP'):