QGIS/python/core/qgsgeometrysimplifier.sip

/** 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;
};