Use a QgsFeedback instead of QProgressBar for QgsNineCellFilter

Gives progress reports and allows cancelation of processing
aspect algorithm

Author: nyalldawson

doc/api_break.dox

@@ -1663,6 +1663,12 @@ QgsNewVectorLayerDialog        {#qgis_api_break_3_0_QgsNewVectorLayerDialog}
 - selectedCrsId() was removed. Use crs() instead.
 
 
+QgsNineCellFilter        {#qgis_api_break_3_0_QgsNineCellFilter}
+-----------------
+
+- The QProgressBar argument for processRaster was changed to a QgsFeedback object.
+
+
 QgsOSMElement        {#qgis_api_break_3_0_QgsOSMElement}
 -------------
 

python/analysis/raster/qgsninecellfilter.sip

@@ -29,10 +29,10 @@ Constructor that takes input file, output file and output format (GDAL string)
 %End
     virtual ~QgsNineCellFilter();
 
-    int processRaster( QProgressDialog *p );
+    int processRaster( QgsFeedback *feedback = 0 );
 %Docstring
  Starts the calculation, reads from mInputFile and stores the result in mOutputFile
-\param p progress dialog that receives update and that is checked for abort. 0 if no progress bar is needed.
+\param feedback feedback object that receives update and that is checked for cancelation.
 :return: 0 in case of success*
  :rtype: int
 %End

python/plugins/processing/algs/qgis/Aspect.py

@@ -84,6 +84,6 @@ def processAlgorithm(self, parameters, context, feedback):
 
         aspect = QgsAspectFilter(inputFile, outputFile, outputFormat)
         aspect.setZFactor(zFactor)
-        aspect.processRaster(None)
+        aspect.processRaster(feedback)
 
         return {self.OUTPUT_LAYER: outputFile}

src/analysis/raster/qgsninecellfilter.cpp

@@ -18,6 +18,7 @@
 #include "qgsninecellfilter.h"
 #include "qgslogger.h"
 #include "cpl_string.h"
+#include "qgsfeedback.h"
 #include <QProgressDialog>
 #include <QFile>
 
@@ -43,7 +44,7 @@ QgsNineCellFilter::QgsNineCellFilter()
 {
 }
 
-int QgsNineCellFilter::processRaster( QProgressDialog *p )
+int QgsNineCellFilter::processRaster( QgsFeedback *feedback )
 {
   GDALAllRegister();
 
@@ -103,22 +104,17 @@ int QgsNineCellFilter::processRaster( QProgressDialog *p )
 
   float *resultLine = ( float * ) CPLMalloc( sizeof( float ) * xSize );
 
-  if ( p )
-  {
-    p->setMaximum( ySize );
-  }
-
   //values outside the layer extent (if the 3x3 window is on the border) are sent to the processing method as (input) nodata values
   for ( int i = 0; i < ySize; ++i )
   {
-    if ( p )
+    if ( feedback && feedback->isCanceled() )
     {
-      p->setValue( i );
+      break;
     }
 
-    if ( p && p->wasCanceled() )
+    if ( feedback )
     {
-      break;
+      feedback->setProgress( 100.0 * static_cast< double >( i ) / ySize );
     }
 
     if ( i == 0 )
@@ -182,19 +178,14 @@ int QgsNineCellFilter::processRaster( QProgressDialog *p )
     }
   }
 
-  if ( p )
-  {
-    p->setValue( ySize );
-  }
-
   CPLFree( resultLine );
   CPLFree( scanLine1 );
   CPLFree( scanLine2 );
   CPLFree( scanLine3 );
 
   GDALClose( inputDataset );
 
-  if ( p && p->wasCanceled() )
+  if ( feedback && feedback->isCanceled() )
   {
     //delete the dataset without closing (because it is faster)
     GDALDeleteDataset( outputDriver, mOutputFile.toUtf8().constData() );

src/analysis/raster/qgsninecellfilter.h

@@ -22,7 +22,7 @@
 #include "gdal.h"
 #include "qgis_analysis.h"
 
-class QProgressDialog;
+class QgsFeedback;
 
 /** \ingroup analysis
  * Base class for raster analysis methods that work with a 3x3 cell filter and calculate the value of each cell based on
@@ -37,9 +37,9 @@ class ANALYSIS_EXPORT QgsNineCellFilter
     virtual ~QgsNineCellFilter() = default;
 
     /** Starts the calculation, reads from mInputFile and stores the result in mOutputFile
-      \param p progress dialog that receives update and that is checked for abort. 0 if no progress bar is needed.
+      \param feedback feedback object that receives update and that is checked for cancelation.
       \returns 0 in case of success*/
-    int processRaster( QProgressDialog *p );
+    int processRaster( QgsFeedback *feedback = nullptr );
 
     double cellSizeX() const { return mCellSizeX; }
     void setCellSizeX( double size ) { mCellSizeX = size; }