Added preliminary ProxLayer and DataSetLayer in GDAL plugin to aid integration

of GDAL reading into osgTerrain.

include/osgTerrain/Layer

@@ -286,6 +286,25 @@ class OSGTERRAIN_EXPORT CompositeLayer : public Layer
         Layers _layers;
 };
 
+class OSGTERRAIN_EXPORT ProxyLayer : public Layer
+{
+    public:
+
+        ProxyLayer();
+
+        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
+        ProxyLayer(const ProxyLayer& proxyLayer,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
+        
+        META_Object(osgTerrain, ProxyLayer);
+
+
+    protected:
+
+        virtual ~ProxyLayer() {}
+
+
+};
+
 }
 
 #endif

src/osgPlugins/gdal/CMakeLists.txt

@@ -1,6 +1,13 @@
 INCLUDE_DIRECTORIES( ${GDAL_INCLUDE_DIR} )
 
-SET(TARGET_SRC ReaderWriterGDAL.cpp )
+SET(TARGET_SRC
+    ReaderWriterGDAL.cpp
+    DataSetLayer.cpp
+)
+
+SET(TARGET_H
+    DataSetLayer.h
+)
 
 SET(TARGET_LIBRARIES_VARS GDAL_LIBRARY )
 

src/osgPlugins/gdal/DataSetLayer.cpp

@@ -0,0 +1,49 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield 
+ *
+ * This library is open source and may be redistributed and/or modified under  
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * OpenSceneGraph Public License for more details.
+*/
+
+#include "DataSetLayer.h"
+
+using namespace GDALPlugin;
+
+DataSetLayer::DataSetLayer()
+{
+    _dataset = 0;
+}
+
+DataSetLayer::DataSetLayer(const std::string& fileName)
+{
+    setFileName(fileName);
+    _dataset = (GDALDataset*)GDALOpen(fileName.c_str(),GA_ReadOnly);
+}
+
+DataSetLayer::DataSetLayer(const DataSetLayer& dataSetLayer,const osg::CopyOp& copyop):
+    ProxyLayer(dataSetLayer)
+{
+    _dataset = (GDALDataset*)GDALOpen(getFileName().c_str(),GA_ReadOnly);
+}
+
+DataSetLayer::~DataSetLayer()
+{
+    if (_dataset) delete _dataset;
+}
+
+unsigned int DataSetLayer::getNumColumns() const
+{
+    return _dataset!=0 ? _dataset->GetRasterXSize() : 0;
+}
+
+unsigned int DataSetLayer::getNumRows() const
+{
+    return _dataset!=0 ? _dataset->GetRasterYSize() : 0;
+}
+

src/osgPlugins/gdal/DataSetLayer.h

@@ -0,0 +1,51 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield 
+ *
+ * This library is open source and may be redistributed and/or modified under  
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * OpenSceneGraph Public License for more details.
+*/
+
+#ifndef DATASETLAYER
+#define DATASETLAYER 1
+
+#include <osgTerrain/Layer>
+
+#include <gdal_priv.h>
+
+namespace GDALPlugin {
+
+class DataSetLayer : public osgTerrain::ProxyLayer
+{
+    public:
+
+        DataSetLayer();
+
+        DataSetLayer(const std::string& fileName);
+
+        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
+        DataSetLayer(const DataSetLayer& dataSetLayer,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
+        
+        META_Object(GDALPlugin, DataSetLayer);
+        
+        bool valid() const { return _dataset!=0; }
+        
+        virtual unsigned int getNumColumns() const;
+        virtual unsigned int getNumRows() const;
+
+    protected:
+    
+        virtual ~DataSetLayer();
+    
+        GDALDataset* _dataset;
+
+};
+
+}
+
+#endif

src/osgPlugins/gdal/ReaderWriterGDAL.cpp

@@ -13,6 +13,8 @@
 
 #include <gdal_priv.h>
 
+#include "DataSetLayer.h"
+
 #define SERIALIZER() OpenThreads::ScopedLock<OpenThreads::ReentrantMutex> lock(_serializerMutex)  
 
 // From easyrgb.com
@@ -35,6 +37,25 @@ class ReaderWriterGDAL : public osgDB::ReaderWriter
             return osgDB::equalCaseInsensitive(extension,"gdal") || osgDB::equalCaseInsensitive(extension,"gdal");
         }
 
+        virtual ReadResult readObject(const std::string& file, const osgDB::ReaderWriter::Options* options) const
+        {
+            OpenThreads::ScopedLock<OpenThreads::ReentrantMutex> lock(_serializerMutex);
+
+            osg::notify(osg::NOTICE) << "GDALPlugin : " << file << std::endl;
+
+            std::string fileName = osgDB::findDataFile( file, options );
+            if (fileName.empty()) return ReadResult::FILE_NOT_FOUND;
+
+            initGDAL();
+
+            // open a DataSetLayer.
+            osg::ref_ptr<GDALPlugin::DataSetLayer> dataset = new GDALPlugin::DataSetLayer;
+            
+            if (dataset->valid()) return dataset.release();
+            
+            return ReadResult::FILE_NOT_HANDLED;
+        }
+
         virtual ReadResult readImage(const std::string& fileName, const osgDB::ReaderWriter::Options* options) const
         {
             OpenThreads::ScopedLock<OpenThreads::ReentrantMutex> lock(_serializerMutex);
@@ -721,7 +742,7 @@ class ReaderWriterGDAL : public osgDB::ReaderWriter
 
         }
 
-        void initGDAL()
+        void initGDAL() const
         {
             static bool s_initialized = false;
             if (!s_initialized)