Raster shader fixes:

- memory leaks when changing shader functions
- PyQGIS: subclassing of raster shader function instances
- PyQGIS: transfer ownership of the shader function to c++


git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@14022 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: wonder

python/core/qgsrasterlayer.sip

@@ -426,8 +426,9 @@ public:
     /** \brief Mutator that allows the  NO_DATA entry for this raster to be overridden */
     void setNoDataValue( double theNoData );
 
-    /** \brief Set the raster shader function to a user defined function */
-    void setRasterShaderFunction( QgsRasterShaderFunction* theFunction );
+    /** \brief Set the raster shader function to a user defined function
+      \note ownership of the shader function is transfered to raster shader */
+    void setRasterShaderFunction( QgsRasterShaderFunction* theFunction /Transfer/ );
 
     /** \brief Mutator for red band name (allows alternate mappings e.g. map blue as red color) */
     void setRedBandName( const QString & theBandName );

python/core/qgsrastershader.sip

@@ -31,8 +31,9 @@ public:
   bool shade(double, int* /Out/, int* /Out/, int* /Out/);
   /** \brief generates and new RGB value based on original RGB value */
   bool shade(double, double, double, int* /Out/, int* /Out/, int* /Out/);
-  /** \brief A public method that allows the user to set their own shader function */
-  void setRasterShaderFunction(QgsRasterShaderFunction*);
+  /** \brief A public method that allows the user to set their own shader function
+    \note Raster shader takes ownership of the shader function instance */ 
+  void setRasterShaderFunction(QgsRasterShaderFunction* /Transfer/);
   /** \brief Set the maximum value */
   void setMaximumValue(double);
   /** \brief Return the minimum value */

python/core/qgsrastershaderfunction.sip

@@ -3,8 +3,23 @@ class QgsRasterShaderFunction
 {
 %TypeHeaderCode
 #include <qgsrastershaderfunction.h>
+#include <qgscolorrampshader.h>
+#include <qgsfreakoutshader.h>
+#include <qgspseudocolorshader.h>
 %End
 
+%ConvertToSubClassCode
+  if (dynamic_cast<QgsColorRampShader*>(sipCpp) != NULL)
+    sipClass = sipClass_QgsColorRampShader;
+  else if (dynamic_cast<QgsFreakOutShader*>(sipCpp) != NULL)
+    sipClass = sipClass_QgsFreakOutShader;
+  else if (dynamic_cast<QgsPseudoColorShader*>(sipCpp) != NULL)
+    sipClass = sipClass_QgsPseudoColorShader;
+  else
+    sipClass = 0;
+%End
+
+
 public:
   QgsRasterShaderFunction(double theMinimumValue = 0.0, double theMaximumValue = 255.0);
   virtual ~QgsRasterShaderFunction();

src/core/raster/qgsrasterlayer.cpp

@@ -3525,12 +3525,6 @@ void QgsRasterLayer::setNoDataValue( double theNoDataValue )
 
 void QgsRasterLayer::setRasterShaderFunction( QgsRasterShaderFunction* theFunction )
 {
-  //Free old shader if it is not a userdefined shader
-  if ( mColorShadingAlgorithm != QgsRasterLayer::UserDefinedShader && 0 != mRasterShader->rasterShaderFunction() )
-  {
-    delete( mRasterShader->rasterShaderFunction() );
-  }
-
   if ( theFunction )
   {
     mRasterShader->setRasterShaderFunction( theFunction );

src/core/raster/qgsrasterlayer.h

@@ -449,8 +449,8 @@ class CORE_EXPORT QgsRasterLayer : public QgsMapLayer
 
     /** \brief Compute the actual minimum maximum pixel values based on the current (last) display extent */
     void computeMinimumMaximumFromLastExtent( QString theBand, double* theMinMax );
-    
-    /**  \brief Compute the actual minimum maximum pixel values based on the current (last) display extent 
+
+    /**  \brief Compute the actual minimum maximum pixel values based on the current (last) display extent
       \note added in v1.6 */
     void computeMinimumMaximumFromLastExtent( int theBand, double& theMin, double& theMax );
 
@@ -592,7 +592,8 @@ class CORE_EXPORT QgsRasterLayer : public QgsMapLayer
     /** \brief Mutator that allows the  NO_DATA entry for this raster to be overridden */
     void setNoDataValue( double theNoData );
 
-    /** \brief Set the raster shader function to a user defined function */
+    /** \brief Set the raster shader function to a user defined function
+      \note ownership of the shader function is transfered to raster shader */
     void setRasterShaderFunction( QgsRasterShaderFunction* theFunction );
 
     /** \brief Mutator for red band name (allows alternate mappings e.g. map blue as red color) */

src/core/raster/qgsrastershader.cpp

@@ -31,6 +31,7 @@ QgsRasterShader::QgsRasterShader( double theMinimumValue, double theMaximumValue
 
 QgsRasterShader::~QgsRasterShader()
 {
+  delete mRasterShaderFunction;
 }
 
 /**
@@ -84,6 +85,7 @@ void QgsRasterShader::setRasterShaderFunction( QgsRasterShaderFunction* theFunct
 
   if ( 0 != theFunction )
   {
+    delete mRasterShaderFunction;
     mRasterShaderFunction = theFunction;
   }
 }

src/core/raster/qgsrastershader.h

@@ -56,7 +56,8 @@ class CORE_EXPORT QgsRasterShader
     /** \brief generates and new RGB value based on original RGB value */
     bool shade( double, double, double, int*, int*, int* );
 
-    /** \brief A public method that allows the user to set their own shader function */
+    /** \brief A public method that allows the user to set their own shader function
+      \note Raster shader takes ownership of the shader function instance */
     void setRasterShaderFunction( QgsRasterShaderFunction* );
 
     /** \brief Set the maximum value */