qgslabel.h

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/***************************************************************************
                         qgslabel.h - render vector labels
                             -------------------
    begin                : August 2004
    copyright            : (C) 2004 by Radim Blazek
    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 QGSLABEL_H
#define QGSLABEL_H

#include <vector>

#include <QColor>
#include <QList>
#include <QMap>

#include "qgspoint.h"

class QDomNode;
class QDomDocument;
class QDomElement;
class QString;
class QPainter;
class QPaintDevice;

class QgsFeature;
class QgsField;
class QgsLabelAttributes;

#include "qgsfield.h"
#include "qgsrectangle.h"
#include "qgsrendercontext.h"

typedef QList<int> QgsAttributeList;

typedef QMap<int, QgsField> QgsFieldMap;
class QgsFields;

class CORE_EXPORT QgsLabel
{
  public:
    QgsLabel( const QgsFields & fields );

    ~QgsLabel();

    /* Fields */
    enum LabelField
    {
      Text = 0,
      Family,
      Size,
      SizeType,
      Bold,
      Italic,
      Underline,
      Color,
      XCoordinate,
      YCoordinate,
      XOffset,
      YOffset,
      Angle,
      Alignment,
      BufferEnabled,
      BufferSize,
      BufferColor,
      BufferBrush,
      BorderWidth,
      BorderColor,
      BorderStyle,
      MultilineEnabled,
      StrikeOut,     // added in 1.5
      LabelFieldCount
    };

    struct labelpoint
    {
      QgsPoint p;
      double angle;
    };

    void renderLabel( QgsRenderContext &renderContext, QgsFeature &feature, bool selected, QgsLabelAttributes *classAttributes = 0 );

    void readXML( const QDomNode& node );

    void writeXML( QDomNode & label_node, QDomDocument & document ) const;

    void addRequiredFields( QgsAttributeList& fields ) const;

    void setFields( const QgsFields & fields );

    QgsFields & fields();

    QgsLabelAttributes *labelAttributes();

    void setLabelField( int attr, int fieldIndex );

    QString labelField( int attr ) const;

    QString fieldValue( int attr, QgsFeature& feature );

    void setMinScale( float theMinScale );
    float minScale() const;

    void setMaxScale( float theMaxScale );
    float maxScale() const;

    void setScaleBasedVisibility( bool theVisibilityFlag );
    bool scaleBasedVisibility() const;

  private:
    void renderLabel( QgsRenderContext &renderContext, QgsPoint point,
                      QString text, QFont font, QPen pen,
                      int dx, int dy,
                      double xoffset, double yoffset,
                      double ang,
                      int width, int height, int alignment );

    bool readLabelField( QDomElement &el, int attr, QString prefix );

    void labelPoint( std::vector<labelpoint>&, QgsFeature &feature );

    const unsigned char* labelPoint( labelpoint& point, const unsigned char* wkb, size_t wkblen );

    QColor mSelectionColor;

    QgsLabelAttributes *mLabelAttributes;

    QgsFields mFields;

    std::vector<QString> mLabelField;

    std::vector<int> mLabelFieldIdx;

    float mMinScale;
    float mMaxScale;
    bool mScaleBasedVisibility;
};

#endif