Use QgsFeatureSource instead of QgsVectorLayer for QgsKde

nyalldawson · nyalldawson · commit d9e29b974268 · 2017-07-13T20:07:33.000+10:00
Allows generation of heatmaps from feature sources instead
of requiring vector layer inputs
diff --git a/python/analysis/raster/qgskde.sip b/python/analysis/raster/qgskde.sip
@@ -49,9 +49,9 @@ class QgsKernelDensityEstimation
 
     struct Parameters
     {
-      QgsVectorLayer *vectorLayer;
+      QgsFeatureSource *source;
 %Docstring
-Vector point layer
+Point feature source
 %End
 
       double radius;
diff --git a/src/analysis/raster/qgskde.cpp b/src/analysis/raster/qgskde.cpp
@@ -14,7 +14,8 @@
  ***************************************************************************/
 
 #include "qgskde.h"
-#include "qgsvectorlayer.h"
+#include "qgsfeaturesource.h"
+#include "qgsfeatureiterator.h"
 #include "qgsgeometry.h"
 
 #define NO_DATA -9999
@@ -24,7 +25,7 @@
 #endif
 
 QgsKernelDensityEstimation::QgsKernelDensityEstimation( const QgsKernelDensityEstimation::Parameters &parameters, const QString &outputFile, const QString &outputFormat )
-  : mInputLayer( parameters.vectorLayer )
+  : mSource( parameters.source )
   , mOutputFile( outputFile )
   , mOutputFormat( outputFormat )
   , mRadiusField( -1 )
@@ -39,9 +40,9 @@ QgsKernelDensityEstimation::QgsKernelDensityEstimation( const QgsKernelDensityEs
   , mRasterBandH( nullptr )
 {
   if ( !parameters.radiusField.isEmpty() )
-    mRadiusField = mInputLayer->fields().lookupField( parameters.radiusField );
+    mRadiusField = mSource->fields().lookupField( parameters.radiusField );
   if ( !parameters.weightField.isEmpty() )
-    mWeightField = mInputLayer->fields().lookupField( parameters.weightField );
+    mWeightField = mSource->fields().lookupField( parameters.weightField );
 }
 
 QgsKernelDensityEstimation::Result QgsKernelDensityEstimation::run()
@@ -58,7 +59,7 @@ QgsKernelDensityEstimation::Result QgsKernelDensityEstimation::run()
   if ( mWeightField >= 0 )
     requiredAttributes << mWeightField;
 
-  QgsFeatureIterator fit = mInputLayer->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( requiredAttributes ) );
+  QgsFeatureIterator fit = mSource->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( requiredAttributes ) );
 
   QgsFeature f;
   while ( fit.nextFeature( f ) )
@@ -79,7 +80,7 @@ QgsKernelDensityEstimation::Result QgsKernelDensityEstimation::prepare()
     return DriverError;
   }
 
-  if ( !mInputLayer )
+  if ( !mSource )
     return InvalidParameters;
 
   mBounds = calculateBounds();
@@ -235,7 +236,7 @@ bool QgsKernelDensityEstimation::createEmptyLayer( GDALDriverH driver, const Qgs
     return false;
 
   // Set the projection on the raster destination to match the input layer
-  if ( GDALSetProjection( emptyDataset, mInputLayer->crs().toWkt().toLocal8Bit().data() ) != CE_None )
+  if ( GDALSetProjection( emptyDataset, mSource->sourceCrs().toWkt().toLocal8Bit().data() ) != CE_None )
     return false;
 
   GDALRasterBandH poBand = GDALGetRasterBand( emptyDataset, 1 );
@@ -399,16 +400,16 @@ double QgsKernelDensityEstimation::triangularKernel( const double distance, cons
 
 QgsRectangle QgsKernelDensityEstimation::calculateBounds() const
 {
-  if ( !mInputLayer )
+  if ( !mSource )
     return QgsRectangle();
 
-  QgsRectangle bbox = mInputLayer->extent();
+  QgsRectangle bbox = mSource->sourceExtent();
 
   double radius = 0;
   if ( mRadiusField >= 0 )
   {
     // if radius is using a field, find the max value
-    radius = mInputLayer->maximumValue( mRadiusField ).toDouble();
+    radius = mSource->maximumValue( mRadiusField ).toDouble();
   }
   else
   {
diff --git a/src/analysis/raster/qgskde.h b/src/analysis/raster/qgskde.h
@@ -25,7 +25,7 @@
 #include <cpl_conv.h>
 #include "qgis_analysis.h"
 
-class QgsVectorLayer;
+class QgsFeatureSource;
 class QProgressDialog;
 class QgsFeature;
 
@@ -70,8 +70,8 @@ class ANALYSIS_EXPORT QgsKernelDensityEstimation
     //! KDE parameters
     struct Parameters
     {
-      //! Vector point layer
-      QgsVectorLayer *vectorLayer = nullptr;
+      //! Point feature source
+      QgsFeatureSource *source = nullptr;
 
       //! Fixed radius, in map units
       double radius;
@@ -146,7 +146,7 @@ class ANALYSIS_EXPORT QgsKernelDensityEstimation
 
     QgsRectangle calculateBounds() const;
 
-    QgsVectorLayer *mInputLayer = nullptr;
+    QgsFeatureSource *mSource = nullptr;
 
     QString mOutputFile;
     QString mOutputFormat;
