Added single band gray renderer

qgis · Dec 29, 2011 · 46aa6c6 · 46aa6c6
1 parent 2e371eb
commit 46aa6c6
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diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
@@ -169,6 +169,7 @@ SET(QGIS_CORE_SRCS
   raster/qgscubicrasterresampler.cpp
   raster/qgspalettedrasterrenderer.cpp
   raster/qgsmultibandcolorrenderer.cpp
+  raster/qgssinglebandgrayrenderer.cpp
 
   renderer/qgscontinuouscolorrenderer.cpp
   renderer/qgsgraduatedsymbolrenderer.cpp

diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
@@ -41,6 +41,7 @@ email                : tim at linfiniti.com
 #include "qgsbilinearrasterresampler.h"
 #include "qgscubicrasterresampler.h"
 #include "qgsmultibandcolorrenderer.h"
+#include "qgssinglebandgrayrenderer.h"
 
 #include <cstdio>
 #include <cmath>
@@ -815,8 +816,24 @@ void QgsRasterLayer::draw( QPainter * theQPainter,
       }
       else
       {
+        QgsSingleBandGrayRenderer r( mDataProvider, bandNumber( mGrayBandName ), mResampler );
+        r.setOpacity( mTransparencyLevel / 255.0 );
+        r.setRasterTransparency( &mRasterTransparency );
+        if ( mTransparencyBandName != TRSTRING_NOT_SET )
+        {
+          int tBandNr = bandNumber( mTransparencyBandName );
+          if ( tBandNr > 0 )
+          {
+            r.setAlphaBand( tBandNr );
+          }
+        }
+        r.setInvertColor( mInvertColor );
+        r.draw( theQPainter, theRasterViewPort, theQgsMapToPixel );
+
+#if 0
         drawSingleBandGray( theQPainter, theRasterViewPort,
                             theQgsMapToPixel, bandNumber( mGrayBandName ) );
+#endif //0
         break;
       }
       // a "Gray" or "Undefined" layer drawn using a pseudocolor algorithm

diff --git a/src/core/raster/qgssinglebandgrayrenderer.cpp b/src/core/raster/qgssinglebandgrayrenderer.cpp
@@ -0,0 +1,99 @@
+/***************************************************************************
+                         qgssinglebandgrayrenderer.cpp
+                         -----------------------------
+    begin                : December 2011
+    copyright            : (C) 2011 by Marco Hugentobler
+    email                : marco at sourcepole dot ch
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#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 )
+{
+}
+
+QgsSingleBandGrayRenderer::~QgsSingleBandGrayRenderer()
+{
+}
+
+void QgsSingleBandGrayRenderer::draw( QPainter* p, QgsRasterViewPort* viewPort, const QgsMapToPixel* theQgsMapToPixel )
+{
+  if ( !p || !mProvider || !viewPort || !theQgsMapToPixel )
+  {
+    return;
+  }
+
+  double oversamplingX, oversamplingY;
+  startRasterRead( mGrayBand, viewPort, theQgsMapToPixel, oversamplingX, oversamplingY );
+
+  int nCols = 0;
+  int nRows = 0;
+  int topLeftCol = 0;
+  int topLeftRow = 0;
+  QgsRasterDataProvider::DataType rasterType = ( QgsRasterDataProvider::DataType )mProvider->dataType( mGrayBand );
+  void* rasterData;
+  //double currentOpacity = mOpacity;
+  int grayVal;
+
+  while ( readNextRasterPart( mGrayBand, viewPort, nCols, nRows, &rasterData, topLeftCol, topLeftRow ) )
+  {
+    //create image
+    QImage img( nCols, nRows, QImage::Format_ARGB32_Premultiplied );
+    QRgb* imageScanLine = 0;
+    int currentRasterPos = 0;
+
+    for ( int i = 0; i < nRows; ++i )
+    {
+      imageScanLine = ( QRgb* )( img.scanLine( i ) );
+      for ( int j = 0; j < nCols; ++j )
+      {
+        grayVal = readValue( rasterData, rasterType, currentRasterPos );
+        if ( mContrastEnhancement )
+        {
+          grayVal = mContrastEnhancement->enhanceContrast( grayVal );
+        }
+
+        if ( mInvertColor )
+        {
+          grayVal = 255 - grayVal;
+        }
+
+        imageScanLine[j] = qRgba( grayVal, grayVal, grayVal, 255 );
+        ++currentRasterPos;
+      }
+    }
+
+    //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 );
+    }
+  }
+
+  stopRasterRead( mGrayBand );
+}
diff --git a/src/core/raster/qgssinglebandgrayrenderer.h b/src/core/raster/qgssinglebandgrayrenderer.h
@@ -0,0 +1,41 @@
+/***************************************************************************
+                         qgssinglebandgrayrenderer.h
+                         ---------------------------
+    begin                : December 2011
+    copyright            : (C) 2011 by Marco Hugentobler
+    email                : marco at sourcepole dot ch
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSSINGLEBANDGRAYRENDERER_H
+#define QGSSINGLEBANDGRAYRENDERER_H
+
+#include "qgsrasterrenderer.h"
+
+class QgsContrastEnhancement;
+
+class QgsSingleBandGrayRenderer: public QgsRasterRenderer
+{
+  public:
+    QgsSingleBandGrayRenderer( QgsRasterDataProvider* provider, int grayBand, QgsRasterResampler* resampler = 0 );
+    ~QgsSingleBandGrayRenderer();
+
+    virtual void draw( QPainter* p, QgsRasterViewPort* viewPort, const QgsMapToPixel* theQgsMapToPixel );
+
+    const QgsContrastEnhancement* contrastEnhancement() const { return mContrastEnhancement; }
+    void setContrastEnhancement( QgsContrastEnhancement* ce ) { mContrastEnhancement = ce; }
+
+  private:
+    int mGrayBand;
+    QgsContrastEnhancement* mContrastEnhancement;
+};
+
+#endif // QGSSINGLEBANDGRAYRENDERER_H