QtOgre         Embedding Ogre into a qt application
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Note: There is a recent QOgreWidget written by djbe that is tested on Mac and Linux: http://www.ogre3d.org/phpBB2/viewtopic.php?p=258064(external link) Alanic?
However the links pointing to this version are not valid anymore. A code snippet working on Mac OSX 10.6 with Cocoa, Qt 4.7.4 and Ogre 1.7.3 was inserted below.
For a similar thread specific to Mac see http://www.ogre3d.org/forums/viewtopic.php?f=2&t=62967(external link).

I found this documentation: Lakin's Ogre-Qt(external link).

It is for Linux.. I prefer to do my development on my Windows machine (it has more ram / better video) and when I develop on Windows I use Visual Studio. As such, these instructions(external link) are priceless.

Once you have Qt built and you've set up your environment variables, you can run qmake on Ogre-Qt to get a vcproj. Open that up in visual studio and the first thing you'll have to do is add the OGRE include directory to the C++ Additional Include Directories. If you try to build now you will see some errors like this:

1>c:\qt-4.2.3-msvc2005\include\qtcore\../../src/corelib/tools/qhash.h(175) : error C2872: 'uint' : ambiguous symbol
1>        could be 'c:\qt-4.2.3-msvc2005\include\qtcore\../../src/corelib/global/qglobal.h(632) : unsigned int uint'
1>        or 'c:\ogresdk\include\OgrePrerequisites.h(134) : Ogre::uint'

 
There's a whole bunch of these, you need to add :: to the front of any reference to uint in the Qt code. You shouldn't need to recompile Qt after you do this.

Then you need to add the OGRE lib directory to the Linker Additional Library Directories and add OgreMain.lib to Linker Inputs.

For the debug configuration you will want to do the same but use OgreMain_d.lib.

Of course, so far my success rate hasn't been too high.

An Example using QT4 and Ogre Eihort

This is a standard QT Widget with an Ogre instance in it. You can create one on QT's designer by elevating a regular widget to an "OgreWidget" and including ogrewidget.h in your project. You'll probably want to do something about the chooseRenderer() function, since it doesn't really do much right now. I generally derive another class from this one and reimplement chooseRenderer(), and build my world in that class. Good Luck with it!

ogrewidget.h:

#ifndef __OGREWIDGET_H__
#define __OGREWIDGET_H__
 
#include <OGRE/Ogre.h>
#include <QGLWidget>
#include <QX11Info>
 
class OgreWidget : public QGLWidget
{
  //Q_OBJECT;
 
 public:
  OgreWidget( QWidget *parent=0 ):
    QGLWidget( parent ),
    mOgreWindow(NULL)
    {
      init( "../bin/plugins.cfg", "../bin/ogre.cfg", "../bin/ogre.log" );
    }
 
  virtual ~OgreWidget()
    {
      mOgreRoot->shutdown();
      delete mOgreRoot;
      destroy();
    }
 
 protected:
  virtual void initializeGL();
  virtual void resizeGL( int, int );
  virtual void paintGL();
 
  void init( std::string, std::string, std::string );
 
  virtual Ogre::RenderSystem* chooseRenderer( Ogre::RenderSystemList* );
 
  Ogre::Root *mOgreRoot;
  Ogre::RenderWindow *mOgreWindow;
  Ogre::Camera *mCamera;
  Ogre::Viewport *mViewport;
  Ogre::SceneManager *mSceneMgr;
};
 
#endif

 

ogrewidget.cpp:

#include "ogrewidget.h"
 
#define THIS OgreWidget
 
/**
 * @brief init the object
 * @author kito berg-taylor
 */
void THIS::init( std::string plugins_file,
         std::string ogre_cfg_file,
         std::string ogre_log )
{
  // create the main ogre object
  mOgreRoot = new Ogre::Root( plugins_file, ogre_cfg_file, ogre_log );
 
  // setup a renderer
  Ogre::RenderSystemList *renderers = mOgreRoot->getAvailableRenderers();
  assert( !renderers->empty() ); // we need at least one renderer to do anything useful
 
  Ogre::RenderSystem *renderSystem;
  renderSystem = chooseRenderer( renderers );
 
  assert( renderSystem ); // user might pass back a null renderer, which would be bad!
 
  mOgreRoot->setRenderSystem( renderSystem );
  QString dimensions = QString( "%1x%2" )
                    .arg(this->width())
                    .arg(this->height());
 
  renderSystem->setConfigOption( "Video Mode", dimensions.toStdString() );
 
  // initialize without creating window
  mOgreRoot->getRenderSystem()->setConfigOption( "Full Screen", "No" );
  mOgreRoot->saveConfig();
  mOgreRoot->initialise(false); // don't create a window
}
 
/**
 * @brief setup the rendering context
 * @author Kito Berg-Taylor
 */
void THIS::initializeGL()
{
  //== Creating and Acquiring Ogre Window ==//
 
  // Get the parameters of the window QT created
  Ogre::String winHandle;
#ifdef WIN32
  // Windows code
  winHandle += Ogre::StringConverter::toString((unsigned long)(this->parentWidget()->winId()));
#elif MACOS
  // Mac code, tested on Mac OSX 10.6 using Qt 4.7.4 and Ogre 1.7.3
  Ogre::String winHandle  = Ogre::StringConverter::toString(winId());
#else
  // Unix code
  QX11Info info = x11Info();
  winHandle  = Ogre::StringConverter::toString((unsigned long)(info.display()));
  winHandle += ":";
  winHandle += Ogre::StringConverter::toString((unsigned int)(info.screen()));
  winHandle += ":";
  winHandle += Ogre::StringConverter::toString((unsigned long)(this->parentWidget()->winId()));
#endif
 
 
  Ogre::NameValuePairList params;
#ifndef MACOS
  // code for Windows and Linux
  params["parentWindowHandle"] = winHandle;
  mOgreWindow = mOgreRoot->createRenderWindow( "QOgreWidget_RenderWindow",
                           this->width(),
                           this->height(),
                           false,
                           &params );
 
  mOgreWindow->setActive(true);
  WId ogreWinId = 0x0;
  mOgreWindow->getCustomAttribute( "WINDOW", &ogreWinId );
 
  assert( ogreWinId );
 
  // bug fix, extract geometry
  QRect geo = this->frameGeometry ( );
 
  // create new window
  this->create( ogreWinId );
 
  // set geometrie infos to new window
  this->setGeometry (geo);
 
#else
  // code for Mac
  params["externalWindowHandle"] = winHandle;
  params["macAPI"] = "cocoa";
  params["macAPICocoaUseNSView"] = "true";
  mOgreWindow = mOgreRoot->createRenderWindow("QOgreWidget_RenderWindow",
      width(), height(), false, &params);
  mOgreWindow->setActive(true);
  makeCurrent();
#endif
 
  setAttribute( Qt::WA_PaintOnScreen, true );
  setAttribute( Qt::WA_NoBackground );
 
  //== Ogre Initialization ==//
  Ogre::SceneType scene_manager_type = Ogre::ST_EXTERIOR_CLOSE;
 
  mSceneMgr = mOgreRoot->createSceneManager( scene_manager_type );
  mSceneMgr->setAmbientLight( Ogre::ColourValue(1,1,1) );
 
  mCamera = mSceneMgr->createCamera( "QOgreWidget_Cam" );
  mCamera->setPosition( Ogre::Vector3(0,1,0) );
  mCamera->lookAt( Ogre::Vector3(0,0,0) );
  mCamera->setNearClipDistance( 1.0 );
 
  Ogre::Viewport *mViewport = mOgreWindow->addViewport( mCamera );
  mViewport->setBackgroundColour( Ogre::ColourValue( 0.8,0.8,1 ) );
}
 
/**
 * @brief render a frame
 * @author Kito Berg-Taylor
 */
void THIS::paintGL()
{
  // Be sure to call "OgreWidget->repaint();" to call paintGL
  assert( mOgreWindow );
  mOgreRoot->renderOneFrame();
}
 
/**
 * @brief resize the GL window
 * @author Kito Berg-Taylor
 */
void THIS::resizeGL( int width, int height )
{
  assert( mOgreWindow );
  mOgreWindow->windowMovedOrResized();
}
 
/**
 * @brief choose the right renderer
 * @author Kito Berg-Taylor
 */
Ogre::RenderSystem* THIS::chooseRenderer( Ogre::RenderSystemList *renderers )
{
  // It would probably be wise to do something more friendly 
  // that just use the first available renderer
  return *renderers->begin();
}

 

For OGRE Cthugha (v1.7.3)

In ogrewidget.cpp just replace....

// setup a renderer
  Ogre::RenderSystemList *renderers = mOgreRoot->getAvailableRenderers();
  assert( !renderers->empty() ); // we need at least one renderer to do anything useful
 
  Ogre::RenderSystem *renderSystem;
  renderSystem = chooseRenderer( renderers );
 
  assert( renderSystem ); // user might pass back a null renderer, which would be bad!

 
with

// setup a renderer
  Ogre::RenderSystemList::const_iterator renderers = mOgreRoot->getAvailableRenderers().begin();
  while(renderers != mOgreRoot->getAvailableRenderers().end())
  {
      Ogre::String rName = (*renderers)->getName();
        if (rName == "OpenGL Rendering Subsystem")
            break;
        renderers++;
  }
 
  Ogre::RenderSystem *renderSystem = *renderers;

 

For Qt 5.x.x

In Qt 5.x.x something is wrong with the resizing. The viewport ist positioned outside the visible area, so that
you only see a black widget. To solve this problem you have to replace the following code in ogrewidget.cpp:

void THIS::resizeGL( int width, int height )
{
   assert( mOgreWindow );
   mOgreWindow->windowMovedOrResized();
}

 
with

void THIS::resizeGL( int width, int height )
{
   assert( mOgreWindow );
   mOgreWindow->reposition( this->pos().x(), 
                            this->pos().y() );    
   mOgreWindow->resize( width, height );
   paintGL();
}

 
this

void THIS::paintGL()
{
  // Be sure to call "OgreWidget->repaint();" to call paintGL
  assert( mOgreWindow );
  mOgreRoot->renderOneFrame();
}

 
with

void THIS::paintGL()
{
  // Be sure to call "OgreWidget->repaint();" to call paintGL
  swapBuffers();
  assert( mOgreWindow );
  mOgreRoot->renderOneFrame();
}

 
and this

{
  ...
  setAttribute( Qt::WA_PaintOnScreen, true );
  setAttribute( Qt::WA_NoBackground );
  ...
}

 
with

{
  ...
  setAutoBufferSwap(false);
  setAttribute( Qt::WA_PaintOnScreen, true );
  setAttribute( Qt::WA_NoBackground );
  ...
}

 
To use...

#include <QApplication>
#include <QWidget>
#include "ogrewidget.h"
#include <QVBoxLayout>
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
    QWidget window;
 
    window.resize(800, 600);
    window.setWindowTitle("Simple example");
 
    OgreWidget* ogreWidget = new OgreWidget;
 
    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(ogreWidget);
 
    window.setLayout(layout);
    window.show();
 
    return app.exec();
}

 


Contributors to this page: fernandot127 points  , Siassei181 points  , saftschachtel194 points  , rhaith6 points  , jacmoe180265 points  , cypherluc82 points  , Brit78 points  and Boost .
Page last modified on Tuesday 11 of February, 2014 17:42:54 UTC by fernandot127 points .


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