QGIS/python/core/qgsgeometrysimplifier.sip
Juergen E. Fischer a90be95f7b sip sync
2016-02-14 03:50:49 +01:00

48 lines
1.9 KiB
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/**
* Abstract base class for simplify geometries using a specific algorithm
*/
class QgsAbstractGeometrySimplifier
{
%TypeHeaderCode
#include "qgsgeometrysimplifier.h"
%End
public:
virtual ~QgsAbstractGeometrySimplifier();
//! Returns a simplified version the specified geometry
virtual QgsGeometry* simplify( QgsGeometry* geometry ) const = 0;
//! Simplifies the specified geometry
virtual bool simplifyGeometry( QgsGeometry* geometry ) const = 0;
// MapToPixel simplification helper methods
public:
//! Returns whether the device-envelope can be replaced by its BBOX when is applied the specified tolerance
static bool isGeneralizableByDeviceBoundingBox( const QgsRectangle& envelope, float mapToPixelTol = 1.0f );
//! Returns whether the device-geometry can be replaced by its BBOX when is applied the specified tolerance
static bool isGeneralizableByDeviceBoundingBox( const QVector<QPointF>& points, float mapToPixelTol = 1.0f );
};
/***************************************************************************/
/**
* Implementation of GeometrySimplifier using the Douglas-Peucker algorithm
*
* Simplifies a geometry, ensuring that the result is a valid geometry having the same dimension and number of components as the input.
* The simplification uses a maximum distance difference algorithm similar to the one used in the Douglas-Peucker algorithm.
*/
class QgsTopologyPreservingSimplifier : QgsAbstractGeometrySimplifier
{
%TypeHeaderCode
#include "qgsgeometrysimplifier.h"
%End
public:
QgsTopologyPreservingSimplifier( double tolerance );
virtual ~QgsTopologyPreservingSimplifier();
//! Returns a simplified version the specified geometry
virtual QgsGeometry* simplify( QgsGeometry* geometry ) const;
//! Simplifies the specified geometry
virtual bool simplifyGeometry( QgsGeometry* geometry ) const;
};