adds both simplify and centroid to qgsgeometry -> these will be used by the qgsanalysis branch

cfarmer · cfarmer · commit 1e7c7e86f29b · 2009-03-21T21:53:52.000Z
git-svn-id: http://svn.osgeo.org/qgis/trunk@10392 c8812cc2-4d05-0410-92ff-de0c093fc19c
diff --git a/python/core/qgsgeometry.sip b/python/core/qgsgeometry.sip
@@ -224,6 +224,14 @@ not disjoint with existing polygons of the feature*/
         of segments used to approximate curves */
     QgsGeometry* buffer(double distance, int segments) /Factory/;
 
+    /** Returns a simplified version of this geometry using a specified tolerance value */
+    QgsGeometry* simplify(double tolerance) /Factory/;
+    
+    /** Returns the center of mass of a geometry
+    * @note for line based geometries, the center point of the line is returned,
+    * and for point based geometries, the point itself is returned */
+    QgsGeometry* centroid() /Factory/;
+
     /** Returns the smallest convex polygon that contains all the points in the geometry. */
     QgsGeometry* convexHull() /Factory/;
     
diff --git a/src/core/qgsgeometry.cpp b/src/core/qgsgeometry.cpp
@@ -132,8 +132,10 @@ static GEOSInit geosinit;
 #define GEOSGetInteriorRingN(g,i) GEOSGetInteriorRingN( (GEOSGeometry *)g, i )
 #define GEOSDisjoint(g0,g1) GEOSDisjoint( (GEOSGeometry *)g0, (GEOSGeometry*)g1 )
 #define GEOSIntersection(g0,g1) GEOSIntersection( (GEOSGeometry*) g0, (GEOSGeometry*)g1 )
-#define GEOSBuffer(g, d, s) GEOSBuffer( (GEOSGeometry*) g, d, s)
-#define GEOSArea(g, a) GEOSArea( (GEOSGeometry*) g, a)
+#define GEOSBuffer(g, d, s) GEOSBuffer( (GEOSGeometry*) g, d, s )
+#define GEOSArea(g, a) GEOSArea( (GEOSGeometry*) g, a )
+#define GEOSSimplify(g, t) GEOSSimplify( (GEOSGeometry*) g, t )
+#define GEOSGetCentroid(g) GEOSGetCentroid( (GEOSGeometry*) g )
 
 #define GEOSCoordSeq_getSize(cs,n) GEOSCoordSeq_getSize( (GEOSCoordSequence *) cs, n )
 #define GEOSCoordSeq_getX(cs,i,x) GEOSCoordSeq_getX( (GEOSCoordSequence *)cs, i, x )
@@ -5328,6 +5330,40 @@ QgsGeometry* QgsGeometry::buffer( double distance, int segments )
   CATCH_GEOS( 0 )
 }
 
+QgsGeometry* QgsGeometry::simplify( double tolerance )
+{
+  if ( mGeos == NULL )
+  {
+    exportWkbToGeos();
+  }
+  if ( !mGeos )
+  {
+    return 0;
+  }
+  try
+  {
+    return fromGeosGeom( GEOSSimplify( mGeos, tolerance ) );
+  }
+  CATCH_GEOS( 0 )
+}
+
+QgsGeometry* QgsGeometry::centroid()
+{
+  if ( mGeos == NULL )
+  {
+    exportWkbToGeos();
+  }
+  if ( !mGeos )
+  {
+    return 0;
+  }
+  try
+  {
+    return fromGeosGeom( GEOSGetCentroid( mGeos ) );
+  }
+  CATCH_GEOS( 0 )
+}
+
 QgsGeometry* QgsGeometry::convexHull()
 {
   if ( mGeos == NULL )
@@ -5450,7 +5486,6 @@ QgsGeometry* QgsGeometry::symDifference( QgsGeometry* geometry )
   CATCH_GEOS( 0 )
 }
 
-
 QList<QgsGeometry*> QgsGeometry::asGeometryCollection()
 {
   if ( mGeos == NULL )
diff --git a/src/core/qgsgeometry.h b/src/core/qgsgeometry.h
@@ -128,8 +128,6 @@ class CORE_EXPORT QgsGeometry
     bool isMultipart();
 
 
-
-
     double distance( QgsGeometry& geom );
 
     /**
@@ -269,6 +267,14 @@ class CORE_EXPORT QgsGeometry
     /** Returns a buffer region around this geometry having the given width and with a specified number
         of segments used to approximate curves */
     QgsGeometry* buffer( double distance, int segments );
+    
+    /** Returns a simplified version of this geometry using a specified tolerance value */
+    QgsGeometry* simplify( double tolerance );
+    
+    /** Returns the center of mass of a geometry
+    * @note for line based geometries, the center point of the line is returned,
+    * and for point based geometries, the point itself is returned */
+    QgsGeometry* centroid();
 
     /** Returns the smallest convex polygon that contains all the points in the geometry. */
     QgsGeometry* convexHull();
diff --git a/src/gui/qgsgenericprojectionselector.cpp b/src/gui/qgsgenericprojectionselector.cpp
@@ -40,7 +40,7 @@ void QgsGenericProjectionSelector::setMessage( QString theMessage )
   {
     // Set up text edit pane
     QString format( "<h2>%1</h2>%2 %3" );
-    QString header = tr( "Define this layer's projection:" );
+    QString header = tr( "Define this layer's coordinate reference system:" );
     QString sentence1 = tr( "This layer appears to have no projection specification." );
     QString sentence2 = tr( "By default, this layer will now have its projection set to that of the project, "
                             "but you may override this by selecting a different projection below." );
diff --git a/src/ui/qgsgenericprojectionselectorbase.ui b/src/ui/qgsgenericprojectionselectorbase.ui
@@ -10,10 +10,12 @@
    </rect>
   </property>
   <property name="windowTitle" >
-   <string>Projection Selector</string>
+   <string>Coordinate Reference System Selector</string>
   </property>
   <property name="windowIcon" >
-   <iconset/>
+   <iconset>
+    <normaloff/>
+   </iconset>
   </property>
   <property name="modal" >
    <bool>true</bool>
@@ -53,7 +55,7 @@
    <item row="2" column="0" >
     <widget class="QDialogButtonBox" name="buttonBox" >
      <property name="standardButtons" >
-      <set>QDialogButtonBox::Cancel|QDialogButtonBox::NoButton|QDialogButtonBox::Ok</set>
+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
      </property>
     </widget>
    </item>

Original file line number	Diff line number	Diff line change
`@@ -40,7 +40,7 @@ void QgsGenericProjectionSelector::setMessage( QString theMessage )`
`40`	`40`	`{`
`41`	`41`	`// Set up text edit pane`
`42`	`42`	`QString format( "<h2>%1</h2>%2 %3" );`
`43`		`- QString header = tr( "Define this layer's projection:" );`
	`43`	`+ QString header = tr( "Define this layer's coordinate reference system:" );`
`44`	`44`	`QString sentence1 = tr( "This layer appears to have no projection specification." );`
`45`	`45`	`QString sentence2 = tr( "By default, this layer will now have its projection set to that of the project, "`
`46`	`46`	`"but you may override this by selecting a different projection below." );`