Qt Reference Documentation

glbox.cpp Example File

activeqt/opengl/glbox.cpp
 /****************************************************************************
 **
 ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the examples of the Qt Toolkit.
 **
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 ** You may use this file under the terms of the BSD license as follows:
 **
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 ** modification, are permitted provided that the following conditions are
 ** met:
 **   * Redistributions of source code must retain the above copyright
 **     notice, this list of conditions and the following disclaimer.
 **   * Redistributions in binary form must reproduce the above copyright
 **     notice, this list of conditions and the following disclaimer in
 **     the documentation and/or other materials provided with the
 **     distribution.
 **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
 **     the names of its contributors may be used to endorse or promote
 **     products derived from this software without specific prior written
 **     permission.
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 ****************************************************************************/

 /****************************************************************************
 **
 ** This is a simple QGLWidget displaying an openGL wireframe box
 **
 ** The OpenGL code is mostly borrowed from Brian Pauls "spin" example
 ** in the Mesa distribution
 **
 ****************************************************************************/

 #include "glbox.h"
 #include <QAxAggregated>
 #include <QUuid>
 #include <objsafe.h>

 #if defined(Q_CC_MSVC)
 #pragma warning(disable:4305) // init: truncation from const double to float
 #endif

 /*!
   Create a GLBox widget
 */

 GLBox::GLBox( QWidget* parent, const char* name )
     : QGLWidget( parent )
 {
     xRot = yRot = zRot = 0.0;           // default object rotation
     scale = 1.25;                       // default object scale
     object = 0;
 }

 /*!
   Release allocated resources
 */

 GLBox::~GLBox()
 {
     makeCurrent();
     glDeleteLists( object, 1 );
 }

 /*!
   Paint the box. The actual openGL commands for drawing the box are
   performed here.
 */

 void GLBox::paintGL()
 {
     glClear( GL_COLOR_BUFFER_BIT );

     glLoadIdentity();
     glTranslatef( 0.0, 0.0, -10.0 );
     glScalef( scale, scale, scale );

     glRotatef( xRot, 1.0, 0.0, 0.0 );
     glRotatef( yRot, 0.0, 1.0, 0.0 );
     glRotatef( zRot, 0.0, 0.0, 1.0 );

     glCallList( object );
 }

 /*!
   Set up the OpenGL rendering state, and define display list
 */

 void GLBox::initializeGL()
 {
     qglClearColor(Qt::black);           // Let OpenGL clear to black
     object = makeObject();              // Generate an OpenGL display list
     glShadeModel( GL_FLAT );
 }

 /*!
   Set up the OpenGL view port, matrix mode, etc.
 */

 void GLBox::resizeGL( int w, int h )
 {
     glViewport( 0, 0, (GLint)w, (GLint)h );
     glMatrixMode( GL_PROJECTION );
     glLoadIdentity();
     glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 15.0 );
     glMatrixMode( GL_MODELVIEW );
 }

 /*!
   Generate an OpenGL display list for the object to be shown, i.e. the box
 */

 GLuint GLBox::makeObject()
 {
     GLuint list;

     list = glGenLists( 1 );

     glNewList( list, GL_COMPILE );

     qglColor(Qt::white);                      // Shorthand for glColor3f or glIndex

     glLineWidth( 2.0 );

     glBegin( GL_LINE_LOOP );
     glVertex3f(  1.0,  0.5, -0.4 );
     glVertex3f(  1.0, -0.5, -0.4 );
     glVertex3f( -1.0, -0.5, -0.4 );
     glVertex3f( -1.0,  0.5, -0.4 );
     glEnd();

     glBegin( GL_LINE_LOOP );
     glVertex3f(  1.0,  0.5, 0.4 );
     glVertex3f(  1.0, -0.5, 0.4 );
     glVertex3f( -1.0, -0.5, 0.4 );
     glVertex3f( -1.0,  0.5, 0.4 );
     glEnd();

     glBegin( GL_LINES );
     glVertex3f(  1.0,  0.5, -0.4 );   glVertex3f(  1.0,  0.5, 0.4 );
     glVertex3f(  1.0, -0.5, -0.4 );   glVertex3f(  1.0, -0.5, 0.4 );
     glVertex3f( -1.0, -0.5, -0.4 );   glVertex3f( -1.0, -0.5, 0.4 );
     glVertex3f( -1.0,  0.5, -0.4 );   glVertex3f( -1.0,  0.5, 0.4 );
     glEnd();

     glEndList();

     return list;
 }

 /*!
   Set the rotation angle of the object to \e degrees around the X axis.
 */

 void GLBox::setXRotation( int degrees )
 {
     xRot = (GLfloat)(degrees % 360);
     updateGL();
 }

 /*!
   Set the rotation angle of the object to \e degrees around the Y axis.
 */

 void GLBox::setYRotation( int degrees )
 {
     yRot = (GLfloat)(degrees % 360);
     updateGL();
 }

 /*!
   Set the rotation angle of the object to \e degrees around the Z axis.
 */

 void GLBox::setZRotation( int degrees )
 {
     zRot = (GLfloat)(degrees % 360);
     updateGL();
 }

 class ObjectSafetyImpl : public QAxAggregated,
                          public IObjectSafety
 {
 public:
     ObjectSafetyImpl() {}

     long queryInterface( const QUuid &iid, void **iface )
     {
         *iface = 0;
         if ( iid == IID_IObjectSafety )
             *iface = (IObjectSafety*)this;
         else
             return E_NOINTERFACE;

         AddRef();
         return S_OK;
     }

     QAXAGG_IUNKNOWN;

     HRESULT WINAPI GetInterfaceSafetyOptions( REFIID riid, DWORD *pdwSupportedOptions, DWORD *pdwEnabledOptions )
     {
         *pdwSupportedOptions = INTERFACESAFE_FOR_UNTRUSTED_DATA | INTERFACESAFE_FOR_UNTRUSTED_CALLER;
         *pdwEnabledOptions = INTERFACESAFE_FOR_UNTRUSTED_DATA | INTERFACESAFE_FOR_UNTRUSTED_CALLER;
         return S_OK;
     }
     HRESULT WINAPI SetInterfaceSafetyOptions( REFIID riid, DWORD pdwSupportedOptions, DWORD pdwEnabledOptions )
     {
         return S_OK;
     }
 };

 QAxAggregated *GLBox::createAggregate()
 {
     return new ObjectSafetyImpl();
 }