src/core/symbology-ng/qgsrulebasedrendererv2.h

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/***************************************************************************
    qgsrulebasedrendererv2.h - Rule-based renderer (symbology-ng)
    ---------------------
    begin                : May 2010
    copyright            : (C) 2010 by Martin Dobias
    email                : wonder dot sk at gmail dot com
 ***************************************************************************
 *                                                                         *
 *   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 QGSRULEBASEDRENDERERV2_H
#define QGSRULEBASEDRENDERERV2_H

#include "qgsfield.h"
#include "qgsfeature.h"
#include "qgis.h"

#include "qgsrendererv2.h"

class QgsExpression;

class QgsCategorizedSymbolRendererV2;
class QgsGraduatedSymbolRendererV2;

class CORE_EXPORT QgsRuleBasedRendererV2 : public QgsFeatureRendererV2
{
  public:


    // TODO: use QVarLengthArray instead of QList

    enum FeatureFlags { FeatIsSelected = 1, FeatDrawMarkers = 2 };

    // feature for rendering: QgsFeature and some flags
    struct FeatureToRender
    {
      FeatureToRender( QgsFeature& _f, int _flags ) : feat( _f ), flags( _flags ) {}
      QgsFeature feat;
      int flags; // selected and/or draw markers
    };

    // rendering job: a feature to be rendered with a particular symbol
    // (both f, symbol are _not_ owned by this class)
    struct RenderJob
    {
      RenderJob( FeatureToRender& _ftr, QgsSymbolV2* _s ) : ftr( _ftr ), symbol( _s ) {}
      FeatureToRender& ftr;
      QgsSymbolV2* symbol;
    };

    // render level: a list of jobs to be drawn at particular level
    // (jobs are owned by this class)
    struct RenderLevel
    {
      RenderLevel( int z ): zIndex( z ) {}
      ~RenderLevel() { foreach ( RenderJob* j, jobs ) delete j; }
      int zIndex;
      QList<RenderJob*> jobs;
    };

    // rendering queue: a list of rendering levels
    typedef QList<RenderLevel> RenderQueue;

    class Rule;
    typedef QList<Rule*> RuleList;

    class CORE_EXPORT Rule
    {
      public:
        Rule( QgsSymbolV2* symbol, int scaleMinDenom = 0, int scaleMaxDenom = 0, QString filterExp = QString(),
              QString label = QString(), QString description = QString() );
        //Rule( const Rule& other );
        ~Rule();
        QString dump( int offset = 0 ) const;
        QSet<QString> usedAttributes();
        QgsSymbolV2List symbols();
        QgsLegendSymbolList legendSymbolItems();
        bool isFilterOK( QgsFeature& f ) const;
        bool isScaleOK( double scale ) const;

        QgsSymbolV2* symbol() { return mSymbol; }
        QString label() const { return mLabel; }
        bool dependsOnScale() const { return mScaleMinDenom != 0 || mScaleMaxDenom != 0; }
        int scaleMinDenom() const { return mScaleMinDenom; }
        int scaleMaxDenom() const { return mScaleMaxDenom; }
        QgsExpression* filter() const { return mFilter; }
        QString filterExpression() const { return mFilterExp; }
        QString description() const { return mDescription; }

        void setSymbol( QgsSymbolV2* sym );
        void setLabel( QString label ) { mLabel = label; }
        void setScaleMinDenom( int scaleMinDenom ) { mScaleMinDenom = scaleMinDenom; }
        void setScaleMaxDenom( int scaleMaxDenom ) { mScaleMaxDenom = scaleMaxDenom; }
        void setFilterExpression( QString filterExp ) { mFilterExp = filterExp; initFilter(); }
        void setDescription( QString description ) { mDescription = description; }

        Rule* clone() const;

        void toSld( QDomDocument& doc, QDomElement &element, QgsStringMap props );
        static Rule* createFromSld( QDomElement& element, QGis::GeometryType geomType );

        QDomElement save( QDomDocument& doc, QgsSymbolV2Map& symbolMap );

        bool startRender( QgsRenderContext& context, const QgsVectorLayer *vlayer );
        QSet<int> collectZLevels();
        void setNormZLevels( const QMap<int, int>& zLevelsToNormLevels );

        bool renderFeature( FeatureToRender& featToRender, QgsRenderContext& context, RenderQueue& renderQueue );

        bool willRenderFeature( QgsFeature& feat );

        QgsSymbolV2List symbolsForFeature( QgsFeature& feat );

        RuleList rulesForFeature( QgsFeature& feat );

        void stopRender( QgsRenderContext& context );

        static Rule* create( QDomElement& ruleElem, QgsSymbolV2Map& symbolMap );

        RuleList& children() { return mChildren; }
        RuleList descendants() const { RuleList l; foreach ( Rule *c, mChildren ) { l += c; l += c->children(); } return l; }
        Rule* parent() { return mParent; }

        void appendChild( Rule* rule ) { mChildren.append( rule ); rule->mParent = this; }
        void insertChild( int i, Rule* rule ) { mChildren.insert( i, rule ); rule->mParent = this; }
        void removeChild( Rule* rule ) { mChildren.removeAll( rule ); delete rule; }
        void removeChildAt( int i ) { Rule* rule = mChildren[i]; mChildren.removeAt( i ); delete rule; }
        void takeChild( Rule* rule ) { mChildren.removeAll( rule ); rule->mParent = NULL; }
        Rule* takeChildAt( int i ) { Rule* rule = mChildren.takeAt( i ); rule->mParent = NULL; return rule; }

      protected:
        void initFilter();

        Rule* mParent; // parent rule (NULL only for root rule)
        QgsSymbolV2* mSymbol;
        int mScaleMinDenom, mScaleMaxDenom;
        QString mFilterExp, mLabel, mDescription;
        bool mElseRule;
        RuleList mChildren;

        // temporary
        QgsExpression* mFilter;
        // temporary while rendering
        QList<int> mSymbolNormZLevels;
        RuleList mActiveChildren;
    };


    static QgsFeatureRendererV2* create( QDomElement& element );

    QgsRuleBasedRendererV2( QgsRuleBasedRendererV2::Rule* root );
    QgsRuleBasedRendererV2( QgsSymbolV2* defaultSymbol );

    ~QgsRuleBasedRendererV2();

    virtual QgsSymbolV2* symbolForFeature( QgsFeature& feature );

    virtual bool renderFeature( QgsFeature& feature, QgsRenderContext& context, int layer = -1, bool selected = false, bool drawVertexMarker = false );

    virtual void startRender( QgsRenderContext& context, const QgsVectorLayer *vlayer );

    virtual void stopRender( QgsRenderContext& context );

    virtual QList<QString> usedAttributes();

    virtual QgsFeatureRendererV2* clone();

    virtual void toSld( QDomDocument& doc, QDomElement &element ) const;

    static QgsFeatureRendererV2* createFromSld( QDomElement& element, QGis::GeometryType geomType );

    virtual QgsSymbolV2List symbols();

    virtual QDomElement save( QDomDocument& doc );

    virtual QgsLegendSymbologyList legendSymbologyItems( QSize iconSize );

    virtual QgsLegendSymbolList legendSymbolItems();

    virtual QString dump();

    virtual bool willRenderFeature( QgsFeature& feat );

    virtual QgsSymbolV2List symbolsForFeature( QgsFeature& feat );

    virtual int capabilities() { return MoreSymbolsPerFeature | Filter | ScaleDependent; }


    Rule* rootRule() { return mRootRule; }


    static void refineRuleCategories( Rule* initialRule, QgsCategorizedSymbolRendererV2* r );
    static void refineRuleRanges( Rule* initialRule, QgsGraduatedSymbolRendererV2* r );
    static void refineRuleScales( Rule* initialRule, QList<int> scales );

  protected:
    Rule* mRootRule;

    // temporary
    RenderQueue mRenderQueue;
    QList<FeatureToRender> mCurrentFeatures;
};

#endif // QGSRULEBASEDRENDERERV2_H