Merge pull request #3242 from mhugent/full_circle

Change full circle interpretation, fixes #15116
qgis · Jun 27, 2016 · 21b8ef0 · 21b8ef0
2 parents e02661c + 663333d
commit 21b8ef0
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Showing 3 changed files with 41 additions and 4 deletions.
diff --git a/src/core/geometry/qgscircularstringv2.cpp b/src/core/geometry/qgscircularstringv2.cpp
@@ -879,7 +879,7 @@ void QgsCircularStringV2::sumUpArea( double& sum ) const
     //segment is a full circle, p2 is the center point
     if ( p1 == p3 )
     {
-      double r2 = QgsGeometryUtils::sqrDistance2D( p1, p2 );
+      double r2 = QgsGeometryUtils::sqrDistance2D( p1, p2 ) / 4.0;
       sum += M_PI * r2;
       continue;
     }

diff --git a/src/core/geometry/qgsgeometryutils.cpp b/src/core/geometry/qgsgeometryutils.cpp
@@ -359,9 +359,9 @@ void QgsGeometryUtils::circleCenterRadius( const QgsPointV2& pt1, const QgsPoint
   //closed circle
   if ( qgsDoubleNear( pt1.x(), pt3.x() ) && qgsDoubleNear( pt1.y(), pt3.y() ) )
   {
-    centerX = pt2.x();
-    centerY = pt2.y();
-    radius = sqrt( pow( pt2.x() - pt1.x(), 2.0 ) + pow( pt2.y() - pt1.y(), 2.0 ) );
+    centerX = ( pt1.x() + pt2.x() ) / 2.0;
+    centerY = ( pt1.y() + pt2.y() ) / 2.0;
+    radius = sqrt( pow( centerX - pt1.x(), 2.0 ) + pow( centerY - pt1.y(), 2.0 ) );
     return;
   }
 

diff --git a/tests/src/core/testqgsgeometryutils.cpp b/tests/src/core/testqgsgeometryutils.cpp
@@ -44,6 +44,8 @@ class TestQgsGeometryUtils: public QObject
     void testAverageAngle_data();
     void testAverageAngle();
     void testDistanceToVertex();
+    void testCircleCenterRadius_data();
+    void testCircleCenterRadius();
 };
 
 
@@ -361,6 +363,41 @@ void TestQgsGeometryUtils::testDistanceToVertex()
   QCOMPARE( QgsGeometryUtils::distanceToVertex( point, QgsVertexId( 0, 0, 1 ) ), -1.0 );
 }
 
+void TestQgsGeometryUtils::testCircleCenterRadius_data()
+{
+  QTest::addColumn<double>( "x1" );
+  QTest::addColumn<double>( "y1" );
+  QTest::addColumn<double>( "x2" );
+  QTest::addColumn<double>( "y2" );
+  QTest::addColumn<double>( "x3" );
+  QTest::addColumn<double>( "y3" );
+  QTest::addColumn<double>( "expectedRadius" );
+  QTest::addColumn<double>( "expectedCenterX" );
+  QTest::addColumn<double>( "expectedCenterY" );
+
+  QTest::newRow( "circleCenterRadius1" ) << 1.0 << 1.0 << 5.0 << 7.0 << 1.0 << 1.0 << sqrt( 13.0 ) << 3.0 << 4.0;
+  QTest::newRow( "circleCenterRadius1" ) << 0.0 << 2.0 << 2.0 << 2.0 << 0.0 << 2.0 << 1.0 << 1.0 << 2.0;
+}
+
+void TestQgsGeometryUtils::testCircleCenterRadius()
+{
+  QFETCH( double, x1 );
+  QFETCH( double, y1 );
+  QFETCH( double, x2 );
+  QFETCH( double, y2 );
+  QFETCH( double, x3 );
+  QFETCH( double, y3 );
+  QFETCH( double, expectedRadius );
+  QFETCH( double, expectedCenterX );
+  QFETCH( double, expectedCenterY );
+
+  double radius, centerX, centerY;
+  QgsGeometryUtils::circleCenterRadius( QgsPointV2( x1, y1 ), QgsPointV2( x2, y2 ), QgsPointV2( x3, y3 ), radius, centerX, centerY );
+  QVERIFY( qgsDoubleNear( expectedRadius, radius ) );
+  QVERIFY( qgsDoubleNear( expectedCenterX, centerX ) );
+  QVERIFY( qgsDoubleNear( expectedCenterY, centerY ) );
+}
+
 
 QTEST_MAIN( TestQgsGeometryUtils )
 #include "testqgsgeometryutils.moc"