qgssymbolv2.h

/***************************************************************************
 qgssymbolv2.h
 ---------------------
 begin                : November 2009
 copyright            : (C) 2009 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 QGSSYMBOLV2_H
#define QGSSYMBOLV2_H

#include "qgis.h"
#include <QList>
#include <QMap>
#include "qgsmapunitscale.h"

class QColor;
class QImage;
class QPainter;
class QSize;
class QPointF;
class QPolygonF;

class QDomDocument;
class QDomElement;
//class

class QgsFeature;
class QgsFields;
class QgsSymbolLayerV2;
class QgsRenderContext;
class QgsVectorLayer;
class QgsPaintEffect;
class QgsMarkerSymbolLayerV2;
class QgsLineSymbolLayerV2;
class QgsFillSymbolLayerV2;

typedef QList<QgsSymbolLayerV2*> QgsSymbolLayerV2List;

class CORE_EXPORT QgsSymbolV2
{
  public:

    enum OutputUnit
    {
      MM = 0,
      MapUnit,
      Mixed, //mixed units in symbol layers
      Pixel
    };

    typedef QList<OutputUnit> OutputUnitList;

    enum SymbolType
    {
      Marker,
      Line,
      Fill
    };

    enum ScaleMethod
    {
      ScaleArea,
      ScaleDiameter
    };

    enum RenderHint
    {
      DataDefinedSizeScale = 1,
      DataDefinedRotation = 2
    };

    virtual ~QgsSymbolV2();

    //! return new default symbol for specified geometry type
    static QgsSymbolV2* defaultSymbol( QGis::GeometryType geomType );

    SymbolType type() const { return mType; }

    // symbol layers handling

    /**Returns list of symbol layers contained in the symbol.
     * @returns symbol layers list
     * @note added in QGIS 2.7
     * @see symbolLayer
     * @see symbolLayerCount
     */
    QgsSymbolLayerV2List symbolLayers() { return mLayers; }

    /**Returns a specific symbol layers contained in the symbol.
     * @param layer layer number
     * @returns corresponding symbol layer
     * @note added in QGIS 2.7
     * @see symbolLayers
     * @see symbolLayerCount
     */
    QgsSymbolLayerV2* symbolLayer( int layer );

    /**Returns total number of symbol layers contained in the symbol.
     * @returns count of symbol layers
     * @note added in QGIS 2.7
     * @see symbolLayers
     * @see symbolLayer
     */
    int symbolLayerCount() { return mLayers.count(); }

    //! insert symbol layer to specified index
    bool insertSymbolLayer( int index, QgsSymbolLayerV2* layer );

    //! append symbol layer at the end of the list
    bool appendSymbolLayer( QgsSymbolLayerV2* layer );

    //! delete symbol layer at specified index
    bool deleteSymbolLayer( int index );

    //! remove symbol layer from the list and return pointer to it
    QgsSymbolLayerV2* takeSymbolLayer( int index );

    //! delete layer at specified index and set a new one
    bool changeSymbolLayer( int index, QgsSymbolLayerV2 *layer );

    void startRender( QgsRenderContext& context, const QgsFields* fields = 0 );
    void stopRender( QgsRenderContext& context );

    void setColor( const QColor& color );
    QColor color() const;

    //! Draw icon of the symbol that occupyies area given by size using the painter.
    //! Optionally custom context may be given in order to get rendering of symbols that use map units right.
    //! @note customContext parameter added in 2.6
    void drawPreviewIcon( QPainter* painter, QSize size, QgsRenderContext* customContext = 0 );

    QImage asImage( QSize size, QgsRenderContext* customContext = 0 );

    QImage bigSymbolPreviewImage();

    QString dump() const;

    virtual QgsSymbolV2* clone() const = 0;

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

    QgsSymbolV2::OutputUnit outputUnit() const;
    void setOutputUnit( QgsSymbolV2::OutputUnit u );

    QgsMapUnitScale mapUnitScale() const;
    void setMapUnitScale( const QgsMapUnitScale& scale );

    //! Get alpha transparency 1 for opaque, 0 for invisible
    qreal alpha() const { return mAlpha; }
    //! Set alpha transparency 1 for opaque, 0 for invisible
    void setAlpha( qreal alpha ) { mAlpha = alpha; }

    void setRenderHints( int hints ) { mRenderHints = hints; }
    int renderHints() const { return mRenderHints; }

    /**Sets whether features drawn by the symbol should be clipped to the render context's
     * extent. If this option is enabled then features which are partially outside the extent
     * will be clipped. This speeds up rendering of the feature, but may have undesirable
     * side effects for certain symbol types.
     * @param clipFeaturesToExtent set to true to enable clipping (defaults to true)
     * @note added in QGIS 2.9
     * @see clipFeaturesToExtent
     */
    void setClipFeaturesToExtent( bool clipFeaturesToExtent ) { mClipFeaturesToExtent = clipFeaturesToExtent; }

    /**Returns whether features drawn by the symbol will be clipped to the render context's
     * extent. If this option is enabled then features which are partially outside the extent
     * will be clipped. This speeds up rendering of the feature, but may have undesirable
     * side effects for certain symbol types.
     * @returns true if features will be clipped
     * @note added in QGIS 2.9
     * @see setClipFeaturesToExtent
     */
    double clipFeaturesToExtent() const { return mClipFeaturesToExtent; }

    QSet<QString> usedAttributes() const;

    void setLayer( const QgsVectorLayer* layer ) { mLayer = layer; }
    const QgsVectorLayer* layer() const { return mLayer; }

  protected:
    QgsSymbolV2( SymbolType type, QgsSymbolLayerV2List layers ); // can't be instantiated

    QgsSymbolLayerV2List cloneLayers() const;

    //! check whether a symbol layer type can be used within the symbol
    //! (marker-marker, line-line, fill-fill/line)
    bool isSymbolLayerCompatible( SymbolType t );

    SymbolType mType;
    QgsSymbolLayerV2List mLayers;

    /**Symbol opacity (in the range 0 - 1)*/
    qreal mAlpha;

    int mRenderHints;
    bool mClipFeaturesToExtent;

    const QgsVectorLayer* mLayer; //current vectorlayer

};

///////////////////////

class CORE_EXPORT QgsSymbolV2RenderContext
{
  public:
    QgsSymbolV2RenderContext( QgsRenderContext& c, QgsSymbolV2::OutputUnit u, qreal alpha = 1.0, bool selected = false, int renderHints = 0, const QgsFeature* f = 0, const QgsFields* fields = 0, const QgsMapUnitScale& mapUnitScale = QgsMapUnitScale() );
    ~QgsSymbolV2RenderContext();

    QgsRenderContext& renderContext() { return mRenderContext; }
    const QgsRenderContext& renderContext() const { return mRenderContext; }

    QgsSymbolV2::OutputUnit outputUnit() const { return mOutputUnit; }
    void setOutputUnit( QgsSymbolV2::OutputUnit u ) { mOutputUnit = u; }

    QgsMapUnitScale mapUnitScale() const { return mMapUnitScale; }
    void setMapUnitScale( const QgsMapUnitScale& scale ) { mMapUnitScale = scale; }

    //! Get alpha transparency 1 for opaque, 0 for invisible
    qreal alpha() const { return mAlpha; }
    //! Set alpha transparency 1 for opaque, 0 for invisible
    void setAlpha( qreal alpha ) { mAlpha = alpha; }

    bool selected() const { return mSelected; }
    void setSelected( bool selected ) { mSelected = selected; }

    int renderHints() const { return mRenderHints; }
    void setRenderHints( int hints ) { mRenderHints = hints; }

    void setFeature( const QgsFeature* f ) { mFeature = f; }
    //! Current feature being rendered - may be null
    const QgsFeature* feature() const { return mFeature; }

    //! Fields of the layer. Currently only available in startRender() calls
    //! to allow symbols with data-defined properties prepare the expressions
    //! (other times fields() returns null)
    //! @note added in 2.4
    const QgsFields* fields() const { return mFields; }

    double outputLineWidth( double width ) const;
    double outputPixelSize( double size ) const;

    // workaround for sip 4.7. Don't use assignment - will fail with assertion error
    QgsSymbolV2RenderContext& operator=( const QgsSymbolV2RenderContext& );

  private:
    QgsRenderContext& mRenderContext;
    QgsSymbolV2::OutputUnit mOutputUnit;
    QgsMapUnitScale mMapUnitScale;
    qreal mAlpha;
    bool mSelected;
    int mRenderHints;
    const QgsFeature* mFeature; //current feature
    const QgsFields* mFields;
};



//////////////////////



class CORE_EXPORT QgsMarkerSymbolV2 : public QgsSymbolV2
{
  public:
    /** Create a marker symbol with one symbol layer: SimpleMarker with specified properties.
      This is a convenience method for easier creation of marker symbols.
    */
    static QgsMarkerSymbolV2* createSimple( const QgsStringMap& properties );

    QgsMarkerSymbolV2( QgsSymbolLayerV2List layers = QgsSymbolLayerV2List() );

    void setAngle( double angle );
    double angle();

    /** Sets the line angle modification for the symbol's angle. This angle is added to 
     * the marker's rotation and data defined rotation before rendering the symbol, and 
     * is usually used for orienting symbols to match a line's angle.
     * @param lineangle Angle in degrees, valid values are between 0 and 360
     * @note added in QGIS 2.9
    */
    void setLineAngle( double lineAngle );

    void setSize( double size );
    double size();

    void setScaleMethod( QgsSymbolV2::ScaleMethod scaleMethod );
    ScaleMethod scaleMethod();

    void renderPoint( const QPointF& point, const QgsFeature* f, QgsRenderContext& context, int layer = -1, bool selected = false );

    virtual QgsSymbolV2* clone() const override;

  private:

    void renderPointUsingLayer( QgsMarkerSymbolLayerV2* layer, const QPointF& point, QgsSymbolV2RenderContext& context );

};



class CORE_EXPORT QgsLineSymbolV2 : public QgsSymbolV2
{
  public:
    /** Create a line symbol with one symbol layer: SimpleLine with specified properties.
      This is a convenience method for easier creation of line symbols.
    */
    static QgsLineSymbolV2* createSimple( const QgsStringMap& properties );

    QgsLineSymbolV2( QgsSymbolLayerV2List layers = QgsSymbolLayerV2List() );

    void setWidth( double width );
    double width();

    void renderPolyline( const QPolygonF& points, const QgsFeature* f, QgsRenderContext& context, int layer = -1, bool selected = false );

    virtual QgsSymbolV2* clone() const override;

  private:

    void renderPolylineUsingLayer( QgsLineSymbolLayerV2* layer, const QPolygonF& points, QgsSymbolV2RenderContext& context );

};



class CORE_EXPORT QgsFillSymbolV2 : public QgsSymbolV2
{
  public:
    /** Create a fill symbol with one symbol layer: SimpleFill with specified properties.
      This is a convenience method for easier creation of fill symbols.
    */
    static QgsFillSymbolV2* createSimple( const QgsStringMap& properties );

    QgsFillSymbolV2( QgsSymbolLayerV2List layers = QgsSymbolLayerV2List() );
    void setAngle( double angle );
    void renderPolygon( const QPolygonF& points, QList<QPolygonF>* rings, const QgsFeature* f, QgsRenderContext& context, int layer = -1, bool selected = false );

    virtual QgsSymbolV2* clone() const override;

  private:

    void renderPolygonUsingLayer( QgsSymbolLayerV2* layer, const QPolygonF &points, QList<QPolygonF> *rings, QgsSymbolV2RenderContext &context );
    /**Calculates the bounds of a polygon including rings*/
    QRectF polygonBounds( const QPolygonF &points, const QList<QPolygonF> *rings ) const;
    /**Translates the rings in a polygon by a set distance*/
    QList<QPolygonF>* translateRings( const QList<QPolygonF> *rings, double dx, double dy ) const;
};

#endif


/*

QgsSymbolV2* ps = new QgsPointSymbol();

// ----

sl = QgsSymbolLayerV2Registry::instance()->createSymbolLayer("SimpleLine", { "color", "..." })

// (or)

sl = QgsSymbolLayerV2Registry::defaultSymbolLayer(QgsSymbolV2::Line)

// (or)

QgsSymbolLayerV2* sl = new QgsSimpleLineSymbolLayer(x,y,z);
QgsLineSymbol* s = new LineSymbol( [ sl ] );

// ----

rend = QgsSingleSymbolRenderer( new LineSymbol() );
*/