Merge pull request #2367 from manisandro/qgsround

nyalldawson · nyalldawson · commit ff43a5dc1f6e · 2015-10-13T21:11:41.000+11:00
Introduce qgsRound since std::round is available only in C++11 onwards
diff --git a/src/core/geometry/qgsgeos.cpp b/src/core/geometry/qgsgeos.cpp
@@ -1422,11 +1422,11 @@ GEOSCoordSequence* QgsGeos::createCoordinateSequence( const QgsCurveV2* curve, d
       for ( int i = 0; i < numPoints; ++i )
       {
         QgsPointV2 pt = line->pointN( i ); //todo: create method to get const point reference
-        GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, i, std::round( pt.x() / precision ) * precision );
-        GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, i, std::round( pt.y() / precision ) * precision );
+        GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, i, qgsRound( pt.x() / precision ) * precision );
+        GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, i, qgsRound( pt.y() / precision ) * precision );
         if ( hasZ )
         {
-          GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, i, 2, std::round( pt.z() / precision ) * precision );
+          GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, i, 2, qgsRound( pt.z() / precision ) * precision );
         }
         if ( hasM )
         {
@@ -1474,11 +1474,11 @@ GEOSGeometry* QgsGeos::createGeosPoint( const QgsAbstractGeometryV2* point, int
     GEOSCoordSequence* coordSeq = GEOSCoordSeq_create_r( geosinit.ctxt, 1, coordDims );
     if ( precision > 0. )
     {
-      GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, 0, std::round( pt->x() / precision ) * precision );
-      GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, 0, std::round( pt->y() / precision ) * precision );
+      GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, 0, qgsRound( pt->x() / precision ) * precision );
+      GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, 0, qgsRound( pt->y() / precision ) * precision );
       if ( pt->is3D() )
       {
-        GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, 0, 2, std::round( pt->z() / precision ) * precision );
+        GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, 0, 2, qgsRound( pt->z() / precision ) * precision );
       }
     }
     else
diff --git a/src/core/qgis.h b/src/core/qgis.h
@@ -289,6 +289,14 @@ inline bool qgsDoubleNearSig( double a, double b, int significantDigits = 10 )
          qRound( ar * pow( 10.0, significantDigits ) ) == qRound( br * pow( 10.0, significantDigits ) );
 }
 
+//
+// a round function which returns a double to guard against overflows
+//
+inline double qgsRound( double x )
+{
+  return x < 0.0 ? std::ceil( x - 0.5 ) : std::floor( x + 0.5 );
+}
+
 bool qgsVariantLessThan( const QVariant& lhs, const QVariant& rhs );
 
 bool qgsVariantGreaterThan( const QVariant& lhs, const QVariant& rhs );
diff --git a/tests/src/core/testqgis.cpp b/tests/src/core/testqgis.cpp
@@ -36,6 +36,7 @@ class TestQGis : public QObject
     void permissiveToDouble();
     void permissiveToInt();
     void doubleToString();
+    void qgsround();
 
   private:
     QString mReport;
@@ -136,5 +137,19 @@ void TestQGis::doubleToString()
   QCOMPARE( qgsDoubleToString( 12345, -1 ), QString( "12345" ) );
 }
 
+void TestQGis::qgsround()
+{
+  QCOMPARE( qgsRound( 3.141592653589793 ), 3. );
+  QCOMPARE( qgsRound( 2.718281828459045 ), 3. );
+  QCOMPARE( qgsRound( -3.141592653589793 ), -3. );
+  QCOMPARE( qgsRound( -2.718281828459045 ), -3. );
+  QCOMPARE( qgsRound( 314159265358979.3 ), 314159265358979. );
+  QCOMPARE( qgsRound( 2718281828459.045 ), 2718281828459. );
+  QCOMPARE( qgsRound( -314159265358979.3 ), -314159265358979. );
+  QCOMPARE( qgsRound( -2718281828459.045 ), -2718281828459. );
+  QCOMPARE( qgsRound( 1.5 ), 2. );
+  QCOMPARE( qgsRound( -1.5 ), -2. );
+}
+
 QTEST_MAIN( TestQGis )
 #include "testqgis.moc"

Original file line number	Diff line number	Diff line change
`@@ -1422,11 +1422,11 @@ GEOSCoordSequence* QgsGeos::createCoordinateSequence( const QgsCurveV2* curve, d`
`1422`	`1422`	`for ( int i = 0; i < numPoints; ++i )`
`1423`	`1423`	`{`
`1424`	`1424`	`QgsPointV2 pt = line->pointN( i ); //todo: create method to get const point reference`
`1425`		`- GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, i, std::round( pt.x() / precision ) * precision );`
`1426`		`- GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, i, std::round( pt.y() / precision ) * precision );`
	`1425`	`+ GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, i, qgsRound( pt.x() / precision ) * precision );`
	`1426`	`+ GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, i, qgsRound( pt.y() / precision ) * precision );`
`1427`	`1427`	`if ( hasZ )`
`1428`	`1428`	`{`
`1429`		`- GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, i, 2, std::round( pt.z() / precision ) * precision );`
	`1429`	`+ GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, i, 2, qgsRound( pt.z() / precision ) * precision );`
`1430`	`1430`	`}`
`1431`	`1431`	`if ( hasM )`
`1432`	`1432`	`{`
`@@ -1474,11 +1474,11 @@ GEOSGeometry* QgsGeos::createGeosPoint( const QgsAbstractGeometryV2* point, int`
`1474`	`1474`	`GEOSCoordSequence* coordSeq = GEOSCoordSeq_create_r( geosinit.ctxt, 1, coordDims );`
`1475`	`1475`	`if ( precision > 0. )`
`1476`	`1476`	`{`
`1477`		`- GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, 0, std::round( pt->x() / precision ) * precision );`
`1478`		`- GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, 0, std::round( pt->y() / precision ) * precision );`
	`1477`	`+ GEOSCoordSeq_setX_r( geosinit.ctxt, coordSeq, 0, qgsRound( pt->x() / precision ) * precision );`
	`1478`	`+ GEOSCoordSeq_setY_r( geosinit.ctxt, coordSeq, 0, qgsRound( pt->y() / precision ) * precision );`
`1479`	`1479`	`if ( pt->is3D() )`
`1480`	`1480`	`{`
`1481`		`- GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, 0, 2, std::round( pt->z() / precision ) * precision );`
	`1481`	`+ GEOSCoordSeq_setOrdinate_r( geosinit.ctxt, coordSeq, 0, 2, qgsRound( pt->z() / precision ) * precision );`
`1482`	`1482`	`}`
`1483`	`1483`	`}`
`1484`	`1484`	`else`