qgsgeometryanalyzer.h

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/***************************************************************************
    qgsgeometryanalyzer.h - QGIS Tools for vector geometry analysis
                             -------------------
    begin                : 19 March 2009
    copyright            : (C) Carson Farmer
    email                : [email protected]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSGEOMETRYANALYZERH
#define QGSGEOMETRYANALYZERH

#include "qgsvectorlayer.h"
#include "qgsfield.h"
#include "qgsfeature.h"
#include "qgsgeometry.h"
#include "qgsfield.h"
#include "qgsdistancearea.h"

class QgsVectorFileWriter;
class QProgressDialog;


class ANALYSIS_EXPORT QgsGeometryAnalyzer
{
  public:

    bool simplify( QgsVectorLayer* layer, const QString& shapefileName, double tolerance,
                   bool onlySelectedFeatures = false, QProgressDialog* p = 0 );

    bool centroids( QgsVectorLayer* layer, const QString& shapefileName,
                    bool onlySelectedFeatures = false, QProgressDialog* p = 0 );

    bool extent( QgsVectorLayer* layer, const QString& shapefileName, bool onlySelectedFeatures = false, QProgressDialog* p = 0 );

    bool buffer( QgsVectorLayer* layer, const QString& shapefileName, double bufferDistance,
                 bool onlySelectedFeatures = false, bool dissolve = false, int bufferDistanceField = -1, QProgressDialog* p = 0 );

    bool convexHull( QgsVectorLayer* layer, const QString& shapefileName, bool onlySelectedFeatures = false,
                     int uniqueIdField = -1, QProgressDialog* p = 0 );

    bool dissolve( QgsVectorLayer* layer, const QString& shapefileName, bool onlySelectedFeatures = false,
                   int uniqueIdField = -1, QProgressDialog* p = 0 );

    bool eventLayer( QgsVectorLayer* lineLayer, QgsVectorLayer* eventLayer, int lineField, int eventField, QgsFeatureIds &unlocatedFeatureIds, const QString& outputLayer,
                     const QString& outputFormat, int locationField1, int locationField2 = -1, int offsetField = -1, double offsetScale = 1.0,
                     bool forceSingleGeometry = false, QgsVectorDataProvider* memoryProvider = 0, QProgressDialog* p = 0 );

    QgsGeometry* locateBetweenMeasures( double fromMeasure, double toMeasure, QgsGeometry* lineGeom );
    QgsGeometry* locateAlongMeasure( double measure, QgsGeometry* lineGeom );

  private:

    QList<double> simpleMeasure( QgsGeometry* geometry );
    double perimeterMeasure( QgsGeometry* geometry, QgsDistanceArea& measure );
    void simplifyFeature( QgsFeature& f, QgsVectorFileWriter* vfw, double tolerance );
    void centroidFeature( QgsFeature& f, QgsVectorFileWriter* vfw );
    void bufferFeature( QgsFeature& f, int nProcessedFeatures, QgsVectorFileWriter* vfw, bool dissolve, QgsGeometry** dissolveGeometry,
                        double bufferDistance, int bufferDistanceField );
    void convexFeature( QgsFeature& f, int nProcessedFeatures, QgsGeometry** dissolveGeometry );
    void dissolveFeature( QgsFeature& f, int nProcessedFeatures, QgsGeometry** dissolveGeometry );

    //helper functions for event layer
    void addEventLayerFeature( QgsFeature& feature, QgsGeometry* geom, QgsGeometry* lineGeom, QgsVectorFileWriter* fileWriter, QgsFeatureList& memoryFeatures, int offsetField = -1, double offsetScale = 1.0,
                               bool forceSingleType = false );
    bool createOffsetGeometry( QgsGeometry* geom, QgsGeometry* lineGeom, double offset );
    QgsPoint createPointOffset( double x, double y, double dist, QgsGeometry* lineGeom ) const;
    const unsigned char* locateBetweenWkbString( const unsigned char* ptr, QgsMultiPolyline& result, double fromMeasure, double toMeasure );
    const unsigned char* locateAlongWkbString( const unsigned char* ptr, QgsMultiPoint& result, double measure );
    static bool clipSegmentByRange( double x1, double y1, double m1, double x2, double y2, double m2, double range1, double range2, QgsPoint& pt1, QgsPoint& pt2, bool& secondPointClipped );
    static void locateAlongSegment( double x1, double y1, double m1, double x2, double y2, double m2, double measure, bool& pt1Ok, QgsPoint& pt1, bool& pt2Ok, QgsPoint& pt2 );
};
#endif //QGSVECTORANALYZER