Provide convenience function to draw image parts for raster renderer

mhugent · mhugent · commit 8ea43ae577b8 · 2011-12-30T10:06:33.000+01:00
diff --git a/src/core/raster/qgsmultibandcolorrenderer.cpp b/src/core/raster/qgsmultibandcolorrenderer.cpp
@@ -16,12 +16,8 @@
  ***************************************************************************/
 
 #include "qgsmultibandcolorrenderer.h"
-#include "qgsmaptopixel.h"
-#include "qgsrasterresampler.h"
 #include "qgsrastertransparency.h"
-#include "qgsrasterviewport.h"
 #include <QImage>
-#include <QPainter>
 #include <QSet>
 
 QgsMultiBandColorRenderer::QgsMultiBandColorRenderer( QgsRasterDataProvider* provider, int redBand, int greenBand, int blueBand, QgsRasterResampler* resampler ):
@@ -43,7 +39,7 @@ void QgsMultiBandColorRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
   QgsRasterDataProvider::DataType redType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mRedBand );
   QgsRasterDataProvider::DataType greenType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mGreenBand );
   QgsRasterDataProvider::DataType blueType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mBlueBand );
-  QgsRasterDataProvider::DataType transparencyType;
+  QgsRasterDataProvider::DataType transparencyType = QgsRasterDataProvider::UnknownDataType;
   if ( mAlphaBand > 0 )
   {
     transparencyType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mAlphaBand );
@@ -58,27 +54,27 @@ void QgsMultiBandColorRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
   }
 
   QMap<int, void*> bandData;
-  void* defaultPointer;
+  void* defaultPointer = 0;
   QSet<int>::const_iterator bandIt = bands.constBegin();
   for ( ; bandIt != bands.constEnd(); ++bandIt )
   {
     bandData.insert( *bandIt, defaultPointer );
     startRasterRead( *bandIt, viewPort, theQgsMapToPixel, oversamplingX, oversamplingY );
   }
 
-  void* redData;
-  void* greenData;
-  void* blueData;
-  void* alphaData;
+  void* redData = 0;
+  void* greenData = 0;
+  void* blueData = 0;
+  void* alphaData = 0;
   int nCols, nRows, topLeftCol, topLeftRow;
 
-  bool readSuccess;
+  bool readSuccess = true;
   while ( true )
   {
     QSet<int>::const_iterator bandIt = bands.constBegin();
     for ( ; bandIt != bands.constEnd(); ++bandIt )
     {
-      readSuccess = readNextRasterPart( *bandIt, viewPort, nCols, nRows, &bandData[*bandIt], topLeftCol, topLeftRow );
+      readSuccess = readSuccess && readNextRasterPart( *bandIt, viewPort, nCols, nRows, &bandData[*bandIt], topLeftCol, topLeftRow );
     }
 
     if ( !readSuccess )
@@ -139,21 +135,7 @@ void QgsMultiBandColorRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
       }
     }
 
-    //draw image
-    //top left position in device coords
-    QPointF tlPoint = QPointF( viewPort->topLeftPoint.x(), viewPort->topLeftPoint.y() );
-    tlPoint += QPointF( topLeftCol / oversamplingX, topLeftRow / oversamplingY );
-
-    if ( mResampler ) //resample to output resolution
-    {
-      QImage dstImg( nCols / oversamplingX + 1.0, nRows / oversamplingY + 1.0, QImage::Format_ARGB32_Premultiplied );
-      mResampler->resample( img, dstImg );
-      p->drawImage( tlPoint, dstImg );
-    }
-    else //use original image
-    {
-      p->drawImage( tlPoint, img );
-    }
+    drawImage( p, viewPort, img, topLeftCol, topLeftRow, nCols, nRows, oversamplingX, oversamplingY );
   }
 
   bandIt = bands.constBegin();
diff --git a/src/core/raster/qgspalettedrasterrenderer.cpp b/src/core/raster/qgspalettedrasterrenderer.cpp
@@ -16,14 +16,9 @@
  ***************************************************************************/
 
 #include "qgspalettedrasterrenderer.h"
-#include "qgscoordinatetransform.h"
-#include "qgsmaptopixel.h"
-#include "qgsrasterresampler.h"
 #include "qgsrastertransparency.h"
-#include "qgsrasterviewport.h"
 #include <QColor>
 #include <QImage>
-#include <QPainter>
 
 QgsPalettedRasterRenderer::QgsPalettedRasterRenderer( QgsRasterDataProvider* provider, int bandNumber,
     QColor* colorArray, int nColors, QgsRasterResampler* resampler ):
@@ -44,7 +39,7 @@ void QgsPalettedRasterRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
   }
 
   double oversamplingX, oversamplingY;
-  QgsRasterDataProvider::DataType transparencyType;
+  QgsRasterDataProvider::DataType transparencyType = QgsRasterDataProvider::UnknownDataType;
   if ( mAlphaBand > 0 )
   {
     transparencyType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mAlphaBand );
@@ -122,30 +117,7 @@ void QgsPalettedRasterRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
       }
     }
 
-    //top left position in device coords
-    QPointF tlPoint = QPointF( viewPort->topLeftPoint.x(), viewPort->topLeftPoint.y() );
-    tlPoint += QPointF( topLeftCol / oversamplingX, topLeftRow / oversamplingY );
-
-    //draw image
-    if ( mResampler ) //resample to output resolution
-    {
-      QImage dstImg( nCols / oversamplingX + 1.0, nRows / oversamplingY + 1.0, QImage::Format_ARGB32_Premultiplied );
-      mResampler->resample( img, dstImg );
-      p->drawImage( tlPoint, dstImg );
-
-      //debug output
-      qWarning("*************************************************");
-      qWarning("topleft:");
-      qWarning( QString::number( tlPoint.x() ).toLocal8Bit().data() );
-      qWarning( QString::number( tlPoint.y() ).toLocal8Bit().data() );
-      qWarning("width/height:");
-      qWarning( QString::number( nCols / oversamplingX ).toLocal8Bit().data() );
-      qWarning( QString::number( nRows / oversamplingY ).toLocal8Bit().data() );
-    }
-    else //use original image
-    {
-      p->drawImage( tlPoint, img );
-    }
+    drawImage( p, viewPort, img, topLeftCol, topLeftRow, nCols, nRows, oversamplingX, oversamplingY );
   }
 
   //stop raster reading
diff --git a/src/core/raster/qgsrasterrenderer.cpp b/src/core/raster/qgsrasterrenderer.cpp
@@ -16,9 +16,12 @@
  ***************************************************************************/
 
 #include "qgsrasterrenderer.h"
+#include "qgsrasterresampler.h"
 #include "qgsrastertransparency.h"
 #include "qgsrasterviewport.h"
 #include "qgsmaptopixel.h"
+#include <QImage>
+#include <QPainter>
 
 QgsRasterRenderer::QgsRasterRenderer( QgsRasterDataProvider* provider, QgsRasterResampler* resampler ): mProvider( provider ), mResampler( resampler ),
     mOpacity( 1.0 ), mRasterTransparency( 0 ), mAlphaBand( -1 ), mInvertColor( false )
@@ -56,7 +59,7 @@ void QgsRasterRenderer::startRasterRead( int bandNumber, QgsRasterViewPort* view
       providerExtent = t.transformBoundingBox( providerExtent );
     }
     double pixelRatio = mapToPixel->mapUnitsPerPixel() / ( providerExtent.width() / mProvider->xSize() );
-    oversampling = pixelRatio > 1.0 ? 2.5 : pixelRatio;
+    oversampling = pixelRatio > 1.0 ? 1.0 : pixelRatio;
   }
 
   //split raster into small portions if necessary
@@ -158,3 +161,28 @@ bool QgsRasterRenderer::usesTransparency() const
 {
   return ( mAlphaBand > 0 || ( mRasterTransparency && !mRasterTransparency->isEmpty() ) || !doubleNear( mOpacity, 1.0 ) );
 }
+
+void QgsRasterRenderer::drawImage( QPainter* p, QgsRasterViewPort* viewPort, const QImage& img, int topLeftCol, int topLeftRow,
+                                   int nCols, int nRows, double oversamplingX, double oversamplingY ) const
+{
+  if ( !p || !viewPort )
+  {
+    return;
+  }
+
+  //top left position in device coords
+  QPointF tlPoint = QPointF( viewPort->topLeftPoint.x(), viewPort->topLeftPoint.y() );
+  tlPoint += QPointF( topLeftCol / oversamplingX, topLeftRow / oversamplingY );
+
+  //draw image
+  if ( mResampler && !( doubleNear( oversamplingX, 1.0 ) && doubleNear( oversamplingY, 1.0 ) ) ) //resampling with factor 1.0 not useful
+  {
+    QImage dstImg( nCols / oversamplingX + 1.0, nRows / oversamplingY + 1.0, QImage::Format_ARGB32_Premultiplied );
+    mResampler->resample( img, dstImg );
+    p->drawImage( tlPoint, dstImg );
+  }
+  else //use original image
+  {
+    p->drawImage( tlPoint, img );
+  }
+}
diff --git a/src/core/raster/qgsrasterrenderer.h b/src/core/raster/qgsrasterrenderer.h
@@ -64,6 +64,8 @@ class QgsRasterRenderer
 
     void startRasterRead( int bandNumber, QgsRasterViewPort* viewPort, const QgsMapToPixel* mapToPixel, double& oversamplingX, double& oversamplingY );
     bool readNextRasterPart( int bandNumber, QgsRasterViewPort* viewPort, int& nCols, int& nRows, void** rasterData, int& topLeftCol, int& topLeftRow );
+    void drawImage( QPainter* p, QgsRasterViewPort* viewPort, const QImage& img, int topLeftCol, int topLeftRow,
+                    int nCols, int nRows, double oversamplingX, double oversamplingY ) const;
     void stopRasterRead( int bandNumber );
 
 
diff --git a/src/core/raster/qgssinglebandgrayrenderer.cpp b/src/core/raster/qgssinglebandgrayrenderer.cpp
@@ -17,10 +17,7 @@
 
 #include "qgssinglebandgrayrenderer.h"
 #include "qgscontrastenhancement.h"
-#include "qgsrasterresampler.h"
-#include "qgsrasterviewport.h"
 #include <QImage>
-#include <QPainter>
 
 QgsSingleBandGrayRenderer::QgsSingleBandGrayRenderer( QgsRasterDataProvider* provider, int grayBand, QgsRasterResampler* resampler ):
     QgsRasterRenderer( provider, resampler ), mGrayBand( grayBand ), mContrastEnhancement( 0 )
@@ -78,21 +75,7 @@ void QgsSingleBandGrayRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort,
       }
     }
 
-    //draw image
-    //top left position in device coords
-    QPointF tlPoint = QPointF( viewPort->topLeftPoint.x(), viewPort->topLeftPoint.y() );
-    tlPoint += QPointF( topLeftCol / oversamplingX, topLeftRow / oversamplingY );
-
-    if ( mResampler ) //resample to output resolution
-    {
-      QImage dstImg( nCols / oversamplingX + 1.0, nRows / oversamplingY + 1.0, QImage::Format_ARGB32_Premultiplied );
-      mResampler->resample( img, dstImg );
-      p->drawImage( tlPoint, dstImg );
-    }
-    else //use original image
-    {
-      p->drawImage( tlPoint, img );
-    }
+    drawImage( p, viewPort, img, topLeftCol, topLeftRow, nCols, nRows, oversamplingX, oversamplingY );
   }
 
   stopRasterRead( mGrayBand );
