Files
OpenSceneGraph/src/osgWidget/PdfReader.cpp
Robert Osfield dd996a3289 Introduced CMake option OSG_PROVIDE_READFILE option that defaults to ON, but when switched to OFF disables the building of the osgDB::read*File() methods,
forcing users to use osgDB::readRef*File() methods.  The later is preferable as it closes a potential threading bug when using paging databases in conjunction
with the osgDB::Registry Object Cache.  This threading bug occurs when one thread gets an object from the Cache via an osgDB::read*File() call where only
a pointer to the object is passed back, so taking a reference to the object is delayed till it gets reassigned to a ref_ptr<>, but at the same time another
thread calls a flush of the Object Cache deleting this object as it's referenceCount is now zero.  Using osgDB::readREf*File() makes sure the a ref_ptr<> is
passed back and the referenceCount never goes to zero.

To ensure the OSG builds when OSG_PROVIDE_READFILE is to OFF the many cases of osgDB::read*File() usage had to be replaced with a ref_ptr<> osgDB::readRef*File()
usage.  The avoid this change causing lots of other client code to be rewritten to handle the use of ref_ptr<> in place of C pointer I introduced a serious of
templte methods in various class to adapt ref_ptr<> to the underly C pointer to be passed to old OSG API's, example of this is found in include/osg/Group:

    bool addChild(Node* child); // old method which can only be used with a Node*

    tempalte<class T> bool addChild(const osg::ref_ptr<T>& child) { return addChild(child.get()); } // adapter template method

These changes together cover 149 modified files, so it's a large submission. This extent of changes are warrent to make use of the Object Cache
and multi-threaded loaded more robust.



git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@15164 16af8721-9629-0410-8352-f15c8da7e697
2015-10-22 13:42:19 +00:00

105 lines
3.1 KiB
C++

/* -*-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, const GeometryHints& hints)
{
open(filename, hints);
}
bool PdfReader::assign(PdfImage* pdfImage, const GeometryHints& hints)
{
if (!pdfImage) return false;
_pdfImage = pdfImage;
_pdfImage->setBackgroundColor(hints.backgroundColor);
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);
osg::ref_ptr<osgViewer::InteractiveImageHandler> iih = new osgViewer::InteractiveImageHandler(_pdfImage.get());
pictureQuad->setEventCallback(iih.get());
pictureQuad->setCullCallback(iih.get());
addDrawable(pictureQuad);
return true;
}
bool PdfReader::open(const std::string& filename, const GeometryHints& hints)
{
osg::ref_ptr<osg::Image> image = osgDB::readRefImageFile(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();
}