Intoduce new osgWidget::PdfReader and osgWidget::VncClient front ends to osgWidget,

with new pdf plugin and updated vnc plugin that now support these front ends.

Updated osgpdf and osgvnc examples to new these new interfaces.

src/osgWidget/PdfReader.cpp

@@ -0,0 +1,100 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2008 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 <osg/Geode>
+#include <osgDB/ReadFile>
+#include <osgViewer/ViewerEventHandlers>
+
+#include <osgWidget/PdfReader>
+
+#include <osg/io_utils>
+
+using namespace osgWidget;
+
+PdfReader::PdfReader(const std::string& filename, GeometryHints hints)
+{
+    open(filename, hints);
+}
+        
+bool PdfReader::assign(PdfImage* pdfImage, GeometryHints hints)
+{
+    if (!pdfImage) return false;
+
+    _pdfImage = pdfImage;
+
+    bool flip = _pdfImage->getOrigin()==osg::Image::TOP_LEFT;
+
+    float aspectRatio = (_pdfImage->t()>0 && _pdfImage->s()>0) ? float(_pdfImage->t()) / float(_pdfImage->s()) : 1.0;
+
+    osg::Vec3 widthVec(hints.widthVec);
+    osg::Vec3 heightVec(hints.heightVec);
+    
+    switch(hints.aspectRatioPolicy)
+    {
+        case(GeometryHints::RESIZE_HEIGHT_TO_MAINTAINCE_ASPECT_RATIO):
+            heightVec *= aspectRatio;
+            break;
+        case(GeometryHints::RESIZE_WIDTH_TO_MAINTAINCE_ASPECT_RATIO):
+            widthVec /= aspectRatio;
+            break;
+        default:
+            // no need to adjust aspect ratio
+            break;
+    }
+    
+    osg::Geometry* pictureQuad = osg::createTexturedQuadGeometry(hints.position, widthVec, heightVec,
+                                       0.0f, flip ? 1.0f : 0.0f , 1.0f, flip ? 0.0f : 1.0f);
+
+    osg::Texture2D* texture = new osg::Texture2D(_pdfImage.get());
+    texture->setResizeNonPowerOfTwoHint(false);
+    texture->setFilter(osg::Texture::MIN_FILTER,osg::Texture::LINEAR);
+    texture->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
+    texture->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
+
+    pictureQuad->getOrCreateStateSet()->setTextureAttributeAndModes(0,
+                texture,
+                osg::StateAttribute::ON);
+
+    pictureQuad->setEventCallback(new osgViewer::InteractiveImageHandler(_pdfImage.get()));
+
+    addDrawable(pictureQuad);
+    
+    return true;
+}
+
+bool PdfReader::open(const std::string& filename, GeometryHints hints)
+{
+    osg::ref_ptr<osg::Image> image = osgDB::readImageFile(filename);
+    return assign(dynamic_cast<PdfImage*>(image.get()), hints);
+}
+
+bool PdfReader::page(int pageNum)
+{
+    if (!_pdfImage) return false;
+    
+    return _pdfImage->page(pageNum);
+}
+
+bool PdfReader::previous()
+{
+    if (!_pdfImage) return false;
+    
+    return _pdfImage->previous();
+}
+
+bool PdfReader::next()
+{
+    if (!_pdfImage) return false;
+    
+    return _pdfImage->next();
+}