scenery: OptionsReadFileCallback for use with reader writer options.

The new callback has a default implementation of the callback
methods that do call back into the registrys callback before
calling the registrys implementation directly.
This is meant to be used together with ReaderWriterOptions that
still want to call back into the normal callback chain of the
registry.

simgear/scene/util/CMakeLists.txt

@@ -4,7 +4,8 @@ set(HEADERS
     CopyOp.hxx
     DeletionManager.hxx
     NodeAndDrawableVisitor.hxx
-	Noise.hxx
+    Noise.hxx
+    OptionsReadFileCallback.hxx
     OsgMath.hxx
     OsgSingleton.hxx
     PrimitiveUtils.hxx
@@ -31,7 +32,8 @@ set(SOURCES
     CopyOp.cxx
     DeletionManager.cxx
     NodeAndDrawableVisitor.cxx
-	Noise.cxx
+    Noise.cxx
+    OptionsReadFileCallback.cxx
     PrimitiveUtils.cxx
     QuadTreeBuilder.cxx
     SGEnlargeBoundingBox.cxx

simgear/scene/util/OptionsReadFileCallback.cxx

@@ -0,0 +1,93 @@
+// Copyright (C) 2012 Mathias Froehlich
+//
+// 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.
+//
+// This program 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 GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+//
+
+#ifdef HAVE_CONFIG_H
+#  include <simgear_config.h>
+#endif
+
+#include "OptionsReadFileCallback.hxx"
+
+#include <osgDB/Registry>
+
+namespace simgear {
+
+OptionsReadFileCallback::~OptionsReadFileCallback()
+{
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::openArchive(const std::string& name, osgDB::ReaderWriter::ArchiveStatus status,
+                                unsigned int indexBlockSizeHint, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->openArchive(name, status, indexBlockSizeHint, options);
+    else
+        return osgDB::ReadFileCallback::openArchive(name, status, indexBlockSizeHint, options);
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::readObject(const std::string& name, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->readObject(name, options);
+    else
+        return osgDB::ReadFileCallback::readObject(name, options);
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::readImage(const std::string& name, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->readImage(name, options);
+    else
+        return osgDB::ReadFileCallback::readImage(name, options);
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::readHeightField(const std::string& name, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->readHeightField(name, options);
+    else
+        return osgDB::ReadFileCallback::readHeightField(name, options);
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::readNode(const std::string& name, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->readNode(name, options);
+    else
+        return osgDB::ReadFileCallback::readNode(name, options);
+}
+
+osgDB::ReaderWriter::ReadResult
+OptionsReadFileCallback::readShader(const std::string& name, const osgDB::Options* options)
+{
+    osgDB::ReadFileCallback* callback = osgDB::Registry::instance()->getReadFileCallback();
+    if (callback)
+        return callback->readShader(name, options);
+    else
+        return osgDB::ReadFileCallback::readShader(name, options);
+}
+
+}

simgear/scene/util/OptionsReadFileCallback.hxx

@@ -0,0 +1,54 @@
+// Copyright (C) 2012 Mathias Froehlich
+//
+// 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.
+//
+// This program 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 GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+//
+
+#ifndef SIMGEAR_READFILECALLBACK_HXX
+#define SIMGEAR_READFILECALLBACK_HXX 1
+
+#include <osgDB/Callbacks>
+
+namespace simgear {
+
+/// Read file callback that calls also back into the registrys read file callback.
+
+class OptionsReadFileCallback : public osgDB::ReadFileCallback {
+public:
+    virtual osgDB::ReaderWriter::ReadResult
+    openArchive(const std::string& name, osgDB::ReaderWriter::ArchiveStatus status,
+                unsigned int indexBlockSizeHint, const osgDB::Options* options);
+
+    virtual osgDB::ReaderWriter::ReadResult
+    readObject(const std::string& name, const osgDB::Options* options);
+
+    virtual osgDB::ReaderWriter::ReadResult
+    readImage(const std::string& name, const osgDB::Options* options);
+    
+    virtual osgDB::ReaderWriter::ReadResult
+    readHeightField(const std::string& name, const osgDB::Options* options);
+
+    virtual osgDB::ReaderWriter::ReadResult
+    readNode(const std::string& name, const osgDB::Options* options);
+
+    virtual osgDB::ReaderWriter::ReadResult
+    readShader(const std::string& name, const osgDB::Options* options);
+
+protected:
+    virtual ~OptionsReadFileCallback();
+};
+
+}
+
+#endif