Add tests for layer blending

tests/src/core/CMakeLists.txt

@@ -91,6 +91,7 @@ ADD_QGIS_TEST(contrastenhancementtest  testcontrastenhancements.cpp)
 ADD_QGIS_TEST(maplayertest testqgsmaplayer.cpp)
 ADD_QGIS_TEST(rendererstest testqgsrenderers.cpp)
 ADD_QGIS_TEST(maprenderertest testqgsmaprenderer.cpp)
+ADD_QGIS_TEST(blendmodestest testqgsblendmodes.cpp)
 ADD_QGIS_TEST(geometrytest testqgsgeometry.cpp)
 ADD_QGIS_TEST(coordinatereferencesystemtest testqgscoordinatereferencesystem.cpp)
 ADD_DEPENDENCIES(qgis_coordinatereferencesystemtest synccrsdb)

tests/src/core/testqgsblendmodes.cpp

@@ -0,0 +1,154 @@
+/***************************************************************************
+     testqgsblendmodes.cpp
+     --------------------------------------
+    Date                 : May 2013
+    Copyright            : (C) 2013 by Nyall Dawson, Tim Sutton
+    Email                : nyall dot dawson at gmail.com
+ ***************************************************************************
+ *                                                                         *
+ *   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 <QtTest>
+#include <QObject>
+#include <QString>
+#include <QStringList>
+#include <QApplication>
+#include <QDir>
+#include <QPainter>
+
+//qgis includes...
+#include <qgsmaprenderer.h>
+#include <qgsmaplayer.h>
+#include <qgsvectorlayer.h>
+#include <qgsapplication.h>
+#include <qgsproviderregistry.h>
+#include <qgsmaplayerregistry.h>
+#include <qgsmultibandcolorrenderer.h>
+#include <qgsrasterlayer.h>
+//qgis test includes
+#include "qgsrenderchecker.h"
+
+/** \ingroup UnitTests
+ * This is a unit test for layer blend modes
+ */
+class TestQgsBlendModes: public QObject
+{
+    Q_OBJECT;
+  private slots:
+    void initTestCase();// will be called before the first testfunction is executed.
+    void cleanupTestCase();// will be called after the last testfunction was executed.
+    void init() {};// will be called before each testfunction is executed.
+    void cleanup() {};// will be called after every testfunction.
+
+    void vectorBlending();
+    void rasterBlending();
+  private:
+    bool imageCheck( QString theType ); //as above
+    QgsMapRenderer * mpMapRenderer;
+    QgsMapLayer * mpPointsLayer;
+    QgsMapLayer * mpPolysLayer;
+    QgsRasterLayer* mRasterLayer1;       
+    QgsRasterLayer* mRasterLayer2;           
+    QString mTestDataDir;
+};
+
+
+void TestQgsBlendModes::initTestCase()
+{
+
+  // init QGIS's paths - true means that all path will be inited from prefix
+  QgsApplication::init();
+  QgsApplication::initQgis();
+  QgsApplication::showSettings();
+
+  //create some objects that will be used in tests
+
+  //create a point layer
+  QString myDataDir( TEST_DATA_DIR ); //defined in CmakeLists.txt
+  mTestDataDir = myDataDir + QDir::separator();
+  QString myPointsFileName = mTestDataDir + "points.shp";
+  QFileInfo myPointFileInfo( myPointsFileName );
+  mpPointsLayer = new QgsVectorLayer( myPointFileInfo.filePath(),
+                                      myPointFileInfo.completeBaseName(), "ogr" );
+  QgsMapLayerRegistry::instance()->addMapLayers(
+    QList<QgsMapLayer *>() << mpPointsLayer );
+
+  //create a poly layer that will be used in tests
+  QString myPolysFileName = mTestDataDir + "polys.shp";
+  QFileInfo myPolyFileInfo( myPolysFileName );
+  mpPolysLayer = new QgsVectorLayer( myPolyFileInfo.filePath(),
+                                     myPolyFileInfo.completeBaseName(), "ogr" );
+  QgsMapLayerRegistry::instance()->addMapLayers(
+    QList<QgsMapLayer *>() << mpPolysLayer );
+    
+  //create two raster layers
+  QFileInfo rasterFileInfo( mTestDataDir +  "landsat.tif" );
+  mRasterLayer1 = new QgsRasterLayer( rasterFileInfo.filePath(),
+                                     rasterFileInfo.completeBaseName() );
+  mRasterLayer2 = new QgsRasterLayer( rasterFileInfo.filePath(),
+                                     rasterFileInfo.completeBaseName() );                                     
+  QgsMultiBandColorRenderer* rasterRenderer = new QgsMultiBandColorRenderer( mRasterLayer1->dataProvider(), 2, 3, 4 );
+  mRasterLayer1->setRenderer( rasterRenderer );
+  mRasterLayer2->setRenderer( rasterRenderer );  
+  QgsMapLayerRegistry::instance()->addMapLayers(
+    QList<QgsMapLayer *>() << mRasterLayer1 );
+  QgsMapLayerRegistry::instance()->addMapLayers(
+    QList<QgsMapLayer *>() << mRasterLayer2);
+
+  mpMapRenderer = new QgsMapRenderer();
+}
+void TestQgsBlendModes::cleanupTestCase()
+{
+
+}
+
+void TestQgsBlendModes::vectorBlending()
+{
+  //Add two vector layers
+  QStringList myLayers;
+  myLayers << mpPointsLayer->id();
+  myLayers << mpPolysLayer->id();
+  mpMapRenderer->setLayerSet( myLayers );
+  
+  //Set blending modes for both layers
+  mpPointsLayer->setBlendMode( QPainter::CompositionMode_Overlay );
+  mpPolysLayer->setBlendMode( QPainter::CompositionMode_Multiply );
+  mpMapRenderer->setExtent( mpPointsLayer->extent() );
+  QVERIFY( imageCheck( "vector_blendmodes" ) );
+}
+
+void TestQgsBlendModes::rasterBlending()
+{
+  //Add two raster layers to map renderer
+  QStringList myLayers;
+  myLayers << mRasterLayer1->id();
+  myLayers << mRasterLayer2->id();  
+  mpMapRenderer->setLayerSet( myLayers );
+  mpMapRenderer->setExtent( mRasterLayer1->extent() );
+  
+  // set blending mode for top layer
+  mRasterLayer1->setBlendMode( QPainter::CompositionMode_Plus );
+  QVERIFY( imageCheck( "raster_blendmodes" ) );
+}
+
+//
+// Private helper functions not called directly by CTest
+//
+
+bool TestQgsBlendModes::imageCheck( QString theTestType )
+{
+  //use the QgsRenderChecker test utility class to
+  //ensure the rendered output matches our control image
+  QgsRenderChecker myChecker;
+  myChecker.setControlName( "expected_" + theTestType );
+  myChecker.setMapRenderer( mpMapRenderer );
+  bool myResultFlag = myChecker.runTest( theTestType );
+  return myResultFlag;
+}
+
+QTEST_MAIN( TestQgsBlendModes )
+#include "moc_testqgsblendmodes.cxx"