Merge pull request #3871 from rouault/auto_stretch

[FEATURE] Implement raster auto-stretching when updating canvas

Author: rouault

doc/api_break.dox

@@ -1313,6 +1313,14 @@ QgsProject        {#qgis_api_break_3_0_QgsProject}
 - clearProperties() was removed. Use clear() instead.
 
 
+QgsRaster        {#qgis_api_break_3_0_QgsRaster}
+---------
+
+- QgsRaster::ContrastEnhancementLimits has been removed, use QgsRasterMinMaxOrigin::Limits
+- QgsRaster::contrastEnhancementLimitsAsString() has been removed, use QgsRasterMinMaxOrigin::limitsString()
+- QgsRaster::contrastEnhancementLimitsFromString() has been removed, use QgsRasterMinMaxOrigin::limitsFromString()
+
+
 QgsRasterCalcNode        {#qgis_api_break_3_0_QgsRasterCalcNode}
 -----------------
 
@@ -1343,13 +1351,18 @@ QgsRasterLayer        {#qgis_api_break_3_0_QgsRasterLayer}
 - setDrawingStyle() was removed. Use setRendererForDrawingStyle() or setRenderer() instead.
 - previewAsPixmap() was removed. Use previewAsImage() instead.
 - updateProgress() had no effect and was removed.
-
+- CUMULATIVE_CUT_LOWER and CUMULATIVE_CUT_UPPER have been moved to QgsRasterMinMaxOrigin
+- the second parameter of setContrastEnhancement() has changed type. It is now QgsRasterMinMaxOrigin::Limits
 
 QgsRasterProjector        {#qgis_api_break_3_0_QgsRasterProjector}
 ------------------
 
 - extentSize() now takes a QgsCoordinateTransform reference, not a pointer. An invalid QgsCoordinateTransform should be used instead of a null pointer if no transformation is required.
 
+QgsRasterRenderer
+-----------------
+
+- MinMaxOrigin enum, minMaxOriginName(), minMaxOriginLabel(), minMaxOriginFromName() removed. Use minMaxOrigin() instead
 
 QgsRelation        {#qgis_api_break_3_0_QgsRelation}
 -----------
@@ -1430,6 +1443,12 @@ QgsSimpleMarkerSymbolLayerWidget        {#qgis_api_break_3_0_QgsSimpleMarkerSymb
 - setName() was removed.
 
 
+QgsSingleBandPseudoColorRenderer        {#qgis_api_break_3_0_QgsSingleBandPseudoColorRenderer}
+--------------------------------
+
+- classificationMinMaxOrigin() and setClassificationMinMaxOrigin() removed. Use minMaxOrigin() and setMinMaxOrigin()
+
+
 QgsSingleSymbolRendererWidget        {#qgis_api_break_3_0_QgsSingleSymbolRendererWidget}
 -----------------------------
 

python/core/core.sip

@@ -274,6 +274,7 @@
 %Include raster/qgsrasterinterface.sip
 %Include raster/qgsrasteriterator.sip
 %Include raster/qgsrasterlayer.sip
+%Include raster/qgsrasterminmaxorigin.sip
 %Include raster/qgsrasternuller.sip
 %Include raster/qgsrasterpipe.sip
 %Include raster/qgsrasterprojector.sip

python/core/raster/qgsraster.sip

@@ -62,14 +62,6 @@ class QgsRaster
       PyramidsErdas,
     };
 
-    /** \brief Contrast enhancement limits */
-    enum ContrastEnhancementLimits
-    {
-      ContrastEnhancementNone,
-      ContrastEnhancementMinMax,
-      ContrastEnhancementStdDev,
-      ContrastEnhancementCumulativeCut
-    };
 
     /** \brief This enumerator describes the different kinds of drawing we can do */
     enum DrawingStyle
@@ -87,9 +79,6 @@ class QgsRaster
       SingleBandColorDataStyle        // ARGB values rendered directly
     };
 
-    static QString contrastEnhancementLimitsAsString( QgsRaster::ContrastEnhancementLimits theLimits );
-    static ContrastEnhancementLimits contrastEnhancementLimitsFromString( const QString& theLimits );
-
     /** Get value representable by given data type.
      * Supported are numerical types Byte, UInt16, Int16, UInt32, Int32, Float32, Float64.
      * @param value

python/core/raster/qgsrasterlayer.sip

@@ -10,11 +10,6 @@ class QgsRasterLayer : QgsMapLayer
 %End
 
   public:
-    /** \brief Default cumulative cut lower limit */
-    static const double CUMULATIVE_CUT_LOWER;
-
-    /** \brief Default cumulative cut upper limit */
-    static const double CUMULATIVE_CUT_UPPER;
 
     /** \brief Default sample size (number of pixels) for estimated statistics/histogram calculation */
     static const double SAMPLE_SIZE;
@@ -165,7 +160,7 @@ class QgsRasterLayer : QgsMapLayer
 
 
     void setContrastEnhancement( QgsContrastEnhancement::ContrastEnhancementAlgorithm theAlgorithm,
-                                 QgsRaster::ContrastEnhancementLimits theLimits = QgsRaster::ContrastEnhancementMinMax,
+                                 QgsRasterMinMaxOrigin::Limits theLimits = QgsRasterMinMaxOrigin::MinMax,
                                  const QgsRectangle& theExtent = QgsRectangle(),
                                  int theSampleSize = QgsRasterLayer::SAMPLE_SIZE,
                                  bool theGenerateLookupTableFlag = true );

python/core/raster/qgsrasterminmaxorigin.sip

@@ -0,0 +1,127 @@
+/** \class QgsRasterMinMaxOrigin
+ * This class describes the origin of min/max values. It does not store by
+ * itself the min/max values.
+ */
+
+class QgsRasterMinMaxOrigin
+{
+%TypeHeaderCode
+#include <qgsrasterminmaxorigin.h>
+%End
+  public:
+    //! \brief Default cumulative cut lower limit
+    static const double CUMULATIVE_CUT_LOWER;
+
+    //! \brief Default cumulative cut upper limit
+    static const double CUMULATIVE_CUT_UPPER;
+
+    //! \brief Default standard deviation factor
+    static const double DEFAULT_STDDEV_FACTOR;
+
+    //! \brief This enumerator describes the limits used to compute min/max values
+    enum Limits
+    {
+      //! User defined.
+      None  /PyName=None_/,
+      //! Real min-max values
+      MinMax,
+      //! Range is [ mean - stdDevFactor() * stddev, mean + stdDevFactor() * stddev ]
+      StdDev,
+      //! Range is [ min + cumulativeCutLower() * (max - min), min + cumulativeCutUpper() * (max - min) ]
+      CumulativeCut
+    };
+
+    //! \brief This enumerator describes the extent used to compute min/max values
+    enum Extent
+    {
+        //! Whole raster is used to compute statistics.
+        WholeRaster,
+        //! Current extent of the canvas (at the time of computation) is used to compute statistics.
+        CurrentCanvas,
+        //! Constantly updated extent of the canvas is used to compute statistics.
+        UpdatedCanvas
+    };
+
+    //! \brief This enumerator describes the accuracy used to compute statistics.
+    enum StatAccuracy
+    {
+        //! Exact statistics.
+        Exact,
+        //! Approximated statistics.
+        Estimated
+    };
+
+    //! \brief Default constructor.
+    QgsRasterMinMaxOrigin();
+
+    //! \brief Equality operator.
+    bool operator ==( const QgsRasterMinMaxOrigin& other ) const;
+
+    //////// Getter methods /////////////////////
+
+    //! \brief Return limits.
+    QgsRasterMinMaxOrigin::Limits limits() const;
+
+    //! \brief Return extent.
+    QgsRasterMinMaxOrigin::Extent extent() const;
+
+    //! \brief Return statistic accuracy.
+    QgsRasterMinMaxOrigin::StatAccuracy statAccuracy() const;
+
+    //! \brief Return lower bound of cumulative cut method (between 0 and 1).
+    double cumulativeCutLower() const;
+
+    //! \brief Return upper bound of cumulative cut method (between 0 and 1).
+    double cumulativeCutUpper() const;
+
+    //! \brief Return factor f so that the min/max range is [ mean - f * stddev , mean + f * stddev ]
+    double stdDevFactor() const;
+
+    //////// Setter methods /////////////////////
+
+    //! \brief Set limits.
+    void setLimits(QgsRasterMinMaxOrigin::Limits theLimits);
+
+    //! \brief Set extent.
+    void setExtent(QgsRasterMinMaxOrigin::Extent theExtent);
+
+    //! \brief Set statistics accuracy.
+    void setStatAccuracy(QgsRasterMinMaxOrigin::StatAccuracy theAccuracy);
+
+    //! \brief Set lower bound of cumulative cut method (between 0 and 1).
+    void setCumulativeCutLower(double val);
+
+    //! \brief Set upper bound of cumulative cut method (between 0 and 1).
+    void setCumulativeCutUpper(double val);
+
+    //! \brief Set factor f so that the min/max range is [ mean - f * stddev , mean + f * stddev ]
+    void setStdDevFactor(double val);
+
+    //////// XML serialization /////////////////////
+
+    //! \brief Serialize object.
+    void writeXml( QDomDocument& doc, QDomElement& parentElem ) const;
+
+    //! \brief Deserialize object.
+    void readXml( const QDomElement& elem );
+
+    //////// Static methods /////////////////////
+
+     //! \brief Return a string to serialize Limits
+    static QString limitsString( QgsRasterMinMaxOrigin::Limits theLimits );
+
+     //! \brief Deserialize Limits
+    static QgsRasterMinMaxOrigin::Limits limitsFromString( const QString& theLimits );
+
+    //! \brief Return a string to serialize Extent
+    static QString extentString( QgsRasterMinMaxOrigin::Extent theExtent );
+
+    //! \brief Deserialize Extent
+    static QgsRasterMinMaxOrigin::Extent extentFromString( const QString& theExtent );
+
+    //! \brief Return a string to serialize StatAccuracy
+    static QString statAccuracyString( QgsRasterMinMaxOrigin::StatAccuracy theAccuracy );
+
+    //! \brief Deserialize StatAccuracy
+    static QgsRasterMinMaxOrigin::StatAccuracy statAccuracyFromString( const QString& theAccuracy );
+};

python/core/raster/qgsrasterrenderer.sip

@@ -6,22 +6,6 @@ class QgsRasterRenderer : QgsRasterInterface
 %End
 
   public:
-    // Origin of min / max values
-    enum MinMaxOrigin
-    {
-      MinMaxUnknown,
-      MinMaxUser, // entered by user
-      // method
-      MinMaxMinMax,
-      MinMaxCumulativeCut,
-      MinMaxStdDev,
-      // Extent
-      MinMaxFullExtent,
-      MinMaxSubExtent,
-      // Precision
-      MinMaxEstimated,
-      MinMaxExact
-    };
 
     static const QRgb NODATA_COLOR;
 
@@ -60,14 +44,16 @@ class QgsRasterRenderer : QgsRasterInterface
     /** Copies common properties like opacity / transparency data from other renderer.
      *  Useful when cloning renderers.
      *  @note added in 2.16  */
-    void copyCommonProperties( const QgsRasterRenderer* other );
+    void copyCommonProperties( const QgsRasterRenderer* other, bool copyMinMaxOrigin = true );
 
     /** Returns a list of band numbers used by the renderer*/
     virtual QList<int> usesBands() const;
 
-    static QString minMaxOriginName( int theOrigin );
-    static QString minMaxOriginLabel( int theOrigin );
-    static int minMaxOriginFromName( const QString& theName );
+    //! Returns const reference to origin of min/max values
+    const QgsRasterMinMaxOrigin& minMaxOrigin() const;
+
+    //! Sets origin of min/max values
+    void setMinMaxOrigin( const QgsRasterMinMaxOrigin& theOrigin );
 
   protected:
 

python/core/raster/qgssinglebandpseudocolorrenderer.sip

@@ -40,8 +40,6 @@ class QgsSingleBandPseudoColorRenderer: QgsRasterRenderer
     double classificationMax() const;
     void setClassificationMin( double min );
     void setClassificationMax( double max );
-    int classificationMinMaxOrigin() const;
-    void setClassificationMinMaxOrigin( int origin );
 
   private:
 

python/gui/raster/qgsmultibandcolorrendererwidget.sip

@@ -19,7 +19,8 @@ class QgsMultiBandColorRendererWidget: QgsRasterRendererWidget
     void setMin( const QString& value, int index = 0 );
     void setMax( const QString& value, int index = 0 );
     int selectedBand( int index = 0 );
+    void doComputations();
 
   public slots:
-    void loadMinMax( int theBandNo, double theMin, double theMax, int theOrigin );
+    void loadMinMax( int theBandNo, double theMin, double theMax );
 };

python/gui/raster/qgsrasterminmaxwidget.sip

@@ -37,9 +37,34 @@ class QgsRasterMinMaxWidget: QWidget
     /** Return the selected sample size. */
     int sampleSize();
 
-    // Load programmaticaly with current values
-    void load();
+    //! \brief Set the "source" of min/max values.
+    void setFromMinMaxOrigin( const QgsRasterMinMaxOrigin& );
+
+    //! \brief Return a QgsRasterMinMaxOrigin object with the widget values.
+    QgsRasterMinMaxOrigin minMaxOrigin();
+
+    //! Hide updated extent radio button
+    void hideUpdatedExtent();
+
+    //! Load programmaticaly with current values
+    void doComputations();
+
+    //! Uncheck cumulative cut, min/max, std-dev radio buttons
+    void userHasSetManualMinMaxValues();
+
+    //! Return if the widget is collaped.
+    bool isCollapsed() const;
+
+    //! Set collapsed state of widget
+    void setCollapsed(bool b);
 
   signals:
-    void load( int theBandNo, double theMin, double theMax, int origin );
+    /**
+     * Emitted when something on the widget has changed.
+     * All widgets will fire this event to notify of an internal change.
+     */
+    void widgetChanged();
+
+    //! signal emitted when new min/max values are computed from statistics.
+    void load( int theBandNo, double theMin, double theMax );
 };

python/gui/raster/qgsrasterrendererwidget.sip

@@ -7,14 +7,6 @@ class QgsRasterRendererWidget: QWidget
     QgsRasterRendererWidget( QgsRasterLayer* layer, const QgsRectangle &extent );
     virtual ~QgsRasterRendererWidget();
 
-    enum LoadMinMaxAlgo
-    {
-      Estimate,
-      Actual,
-      CurrentExtent,
-      CumulativeCut   // 2 - 98% cumulative cut
-    };
-
     virtual QgsRasterRenderer* renderer() = 0 /Factory/;
 
     void setRasterLayer( QgsRasterLayer* layer );
@@ -42,6 +34,8 @@ class QgsRasterRendererWidget: QWidget
     virtual QString stdDev();
     virtual void setStdDev( const QString& value );
     virtual int selectedBand( int index = 0 );
+    virtual void doComputations();
+    virtual QgsRasterMinMaxWidget* minMaxWidget();
 
   signals:
     /**