[FEATURE] Add 'shapeburst' fill style. Shapeburst fills implement a b…

…uffered gradient fill, where a gradient is drawn from the boundary of a polygon towards the polygon's centre. Configurable parameters include distance from the boundary to shade, use of color ramps or simple two color gradients, optional blurring of the fill and offsets.

python/core/composer/qgspaperitem.sip

@@ -2,6 +2,9 @@
  * drawn above all other composer items, while the paper item is drawn below all others.*/
 class QgsPaperGrid : QGraphicsRectItem
 {
+%TypeHeaderCode
+#include <qgspaperitem.h>
+%End
   public:
     QgsPaperGrid( double x, double y, double width, double height, QgsComposition* composition );
     ~QgsPaperGrid();

python/core/symbology-ng/qgsfillsymbollayerv2.sip

@@ -197,6 +197,193 @@ class QgsGradientFillSymbolLayerV2 : QgsFillSymbolLayerV2
 
 };
 
+class QgsShapeburstFillSymbolLayerV2 : QgsFillSymbolLayerV2
+{
+%TypeHeaderCode
+#include <qgsfillsymbollayerv2.h>
+%End
+
+  public:
+
+    enum ShapeburstColorType
+    {
+      SimpleTwoColor,
+      ColorRamp
+    };
+
+    QgsShapeburstFillSymbolLayerV2( QColor color = DEFAULT_SIMPLEFILL_COLOR,
+                                    QColor color2 = Qt::white,
+                                    ShapeburstColorType colorType = SimpleTwoColor,
+                                    int blurRadius = 0,
+                                    bool useWholeShape = true,
+                                    double maxDistance = 5 );
+
+    virtual ~QgsShapeburstFillSymbolLayerV2();
+
+    // static stuff
+
+    static QgsSymbolLayerV2* create( const QgsStringMap& properties = QgsStringMap() ) /Factory/;
+
+    // implemented from base classes
+
+    QString layerType() const;
+
+    void startRender( QgsSymbolV2RenderContext& context );
+
+    void stopRender( QgsSymbolV2RenderContext& context );
+
+    void renderPolygon( const QPolygonF& points, QList<QPolygonF>* rings, QgsSymbolV2RenderContext& context );
+
+    QgsStringMap properties() const;
+
+    QgsSymbolLayerV2* clone() const /Factory/;
+
+    double estimateMaxBleed() const;
+
+    /**Sets the blur radius, which controls the amount of blurring applied to the fill.
+     * @param blurRadius Radius for fill blur. Values between 0 - 17 are valid, where higher values results in a stronger blur. Set to 0 to disable blur.
+     * @note added in 2.3
+     * @see blurRadius
+    */
+    void setBlurRadius( int blurRadius );
+    /**Returns the blur radius, which controls the amount of blurring applied to the fill.
+     * @returns Integer representing the radius for fill blur. Higher values indicate a stronger blur. A 0 value indicates that blurring is disabled.
+     * @note added in 2.3
+     * @see setBlurRadius
+    */
+    int blurRadius() const;
+
+    /**Sets whether the shapeburst fill should be drawn using the entire shape.
+     * @param useWholeShape Set to true if shapeburst should cover entire shape. If false, setMaxDistance is used to calculate how far from the boundary of the shape should
+     * be shaded
+     * @note added in 2.3
+     * @see useWholeShape
+     * @see setMaxDistance
+    */
+    void setUseWholeShape( double useWholeShape );
+    /**Returns whether the shapeburst fill is set to cover the entire shape.
+     * @returns True if shapeburst fill will cover the entire shape. If false, shapeburst is drawn to a distance of maxDistance from the polygon's boundary.
+     * @note added in 2.3
+     * @see setUseWholeShape
+     * @see maxDistance
+    */
+    double useWholeShape() const;
+
+    /**Sets the maximum distance to shape inside of the shape from the polygon's boundary.
+     * @param maxDistance distance from boundary to shade. setUseWholeShape must be set to false for this parameter to take effect. Distance unit is controlled by setDistanceUnit.
+     * @note added in 2.3
+     * @see maxDistance
+     * @see setUseWholeShape
+     * @see setDistanceUnit
+    */
+    void setMaxDistance( double maxDistance );
+    /**Returns the maximum distance from the shape's boundary which is shaded. This parameter is only effective if useWholeShape is false.
+     * @returns the maximum distance from the polygon's boundary which is shaded. Distance units are indicated by distanceUnit.
+     * @note added in 2.3
+     * @see useWholeShape
+     * @see setMaxDistance
+     * @see distanceUnit
+    */
+    double maxDistance() const;
+
+    /**Sets the unit for the maximum distance to shade inside of the shape from the polygon's boundary.
+     * @param unit distance unit for the maximum distance
+     * @note added in 2.3
+     * @see setMaxDistance
+     * @see distanceUnit
+    */
+    void setDistanceUnit( QgsSymbolV2::OutputUnit unit );
+    /**Returns the unit for the maximum distance to shade inside of the shape from the polygon's boundary.
+     * @returns distance unit for the maximum distance
+     * @note added in 2.3
+     * @see maxDistance
+     * @see setDistanceUnit
+    */
+    QgsSymbolV2::OutputUnit distanceUnit() const;
+
+    /**Sets the color mode to use for the shapeburst fill. Shapeburst can either be drawn using a QgsVectorColorRampV2 color ramp
+     * or by simply specificing a start and end color. setColorType is used to specify which mode to use for the fill.
+     * @param colorType color type to use for shapeburst fill
+     * @note added in 2.3
+     * @see colorType
+     * @see setColor
+     * @see setColor2
+     * @see setColorRamp
+    */
+    void setColorType( ShapeburstColorType colorType );
+    /**Returns the color mode used for the shapeburst fill. Shapeburst can either be drawn using a QgsVectorColorRampV2 color ramp
+     * or by simply specificing a start and end color.
+     * @returns current color mode used for the shapeburst fill
+     * @note added in 2.3
+     * @see setColorType
+     * @see color
+     * @see color2
+     * @see colorRamp
+    */
+    ShapeburstColorType colorType() const;
+
+    /**Sets the color ramp used to draw the shapeburst fill. Color ramps are only used if setColorType is set ShapeburstColorType::ColorRamp.
+     * @param ramp color ramp to use for shapeburst fill
+     * @note added in 2.3
+     * @see setColorType
+     * @see colorRamp
+    */
+    void setColorRamp( QgsVectorColorRampV2* ramp );
+    /**Returns the color ramp used for the shapeburst fill. The color ramp is only used if the colorType is set to ShapeburstColorType::ColorRamp
+     * @returns a QgsVectorColorRampV2 color ramp
+     * @note added in 2.3
+     * @see setColorRamp
+     * @see colorType
+    */
+    QgsVectorColorRampV2* colorRamp();
+
+    /**Sets the color for the endpoint of the shapeburst fill. This color is only used if setColorType is set ShapeburstColorType::SimpleTwoColor.
+     * @param color2 QColor to use for endpoint of gradient
+     * @note added in 2.3
+     * @see setColorType
+     * @see color2
+    */
+    void setColor2( QColor color2 );
+    /**Returns the color used for the endpoint of the shapeburst fill. This color is only used if the colorType is set to ShapeburstColorType::SimpleTwoColor
+     * @returns a QColor indicating the color of the endpoint of the gradient
+     * @note added in 2.3
+     * @see setColor2
+     * @see colorType
+    */
+    QColor color2() const;
+
+    /**Sets the offset for the shapeburst fill.
+     * @param offset QPointF indicating the horizontal/vertical offset amount
+     * @note added in 2.3
+     * @see offset
+     * @see setOffsetUnit
+    */
+    void setOffset( QPointF offset );
+    /**Returns the offset for the shapeburst fill.
+     * @returns a QPointF indicating the horizontal/vertical offset amount
+     * @note added in 2.3
+     * @see setOffset
+     * @see offsetUnit
+    */
+    QPointF offset() const;
+
+    /**Sets the units used for the offset for the shapeburst fill.
+     * @param unit units for fill offset
+     * @note added in 2.3
+     * @see setOffset
+     * @see offsetUnit
+    */
+    void setOffsetUnit( QgsSymbolV2::OutputUnit unit );
+    /**Returns the units used for the offset of the shapeburst fill.
+     * @returns units used for the fill offset
+     * @note added in 2.3
+     * @see offset
+     * @see setOffsetUnit
+    */
+    QgsSymbolV2::OutputUnit offsetUnit() const;
+
+};
+
 /**Base class for polygon renderers generating texture images*/
 class QgsImageFillSymbolLayer: QgsFillSymbolLayerV2
 {

python/core/symbology-ng/qgssymbollayerv2utils.sip

@@ -204,6 +204,11 @@ class QgsSymbolLayerV2Utils
      */
     static void blurImageInPlace( QImage& image, const QRect& rect, int radius, bool alphaOnly );
 
+    /** Converts a QColor into a premultiplied ARGB QColor value using a specified alpha value
+     * @note added in 2.3
+     */
+    static void premultiplyColor( QColor& rgb, int alpha );
+
     /**Sorts the passed list in requested order*/
     static void sortVariantList( QList<QVariant>& list, Qt::SortOrder order );
     /**Returns a point on the line from startPoint to directionPoint that is a certain distance away from the starting point*/

python/gui/symbology-ng/qgssymbollayerv2widget.sip

@@ -145,6 +145,35 @@ class QgsGradientFillSymbolLayerV2Widget : QgsSymbolLayerV2Widget
     void on_mSpinAngle_valueChanged( double value );
 };
 
+///////////
+
+class QgsShapeburstFillSymbolLayerV2Widget : QgsSymbolLayerV2Widget
+{
+%TypeHeaderCode
+#include <qgssymbollayerv2widget.h>
+%End
+  public:
+    QgsShapeburstFillSymbolLayerV2Widget( const QgsVectorLayer* vl, QWidget* parent = NULL );
+
+    static QgsSymbolLayerV2Widget* create( const QgsVectorLayer* vl ) /Factory/;
+
+    // from base class
+    virtual void setSymbolLayer( QgsSymbolLayerV2* layer );
+    virtual QgsSymbolLayerV2* symbolLayer();
+
+  public slots:
+    void setColor( const QColor& color );
+    void setColor2( const QColor& color );
+    void colorModeChanged();
+    void on_mSpinBlurRadius_valueChanged( int value );
+    void on_mSpinMaxDistance_valueChanged( double value );
+    void on_mDistanceUnitComboBox_currentIndexChanged( int index );
+    void on_mRadioUseWholeShape_toggled( bool value );
+    void applyColorRamp();
+    void offsetChanged();
+    void on_mOffsetUnitComboBox_currentIndexChanged( int index );
+    void on_mDataDefinedPropertiesButton_clicked();
+};
 
 ///////////