Opengl

[manmohan]

Hi to every one I am't a good programmer with the qt but I am trying to design a widget which has 3 Opengl widgets....

can any one help me with any kind of information that will help to create this... widget...

This widget has a main widget which will be expanding on the hoizontal way only... and then I would like to display 3 cylinders in all the 3 widgets....

I was successful in drawing a single cylinder in the main widget... but after that I have used the same code in the other 2 widgets but there's no display on the screen....

please help me out... I will post my code.... also if necessary....

[manmohan]

Here is the code in the zipped format....
This program was compiled in Linux...
I have created a cpp file and a header file for each of the three widgets so this might be big....

//GLWidget1 this is the main window header file.....
#ifndef GLWIDGET1_H
#define GLWIDGET1_H
#include <QGLWidget>
 class GLWidget : public QGLWidget
 {
     Q_OBJECT
 public:
     GLWidget(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
     void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);
 private:
     GLUquadricObj *pobj;     
     QPoint lastPos;
     GLfloat rotationX, rotationY, rotationZ;
 };
 #endif

//GLWidget1 this is the main window header file.....
#ifndef GLWIDGET1_H
#define GLWIDGET1_H
#include <QGLWidget>
 class GLWidget : public QGLWidget
 {
     Q_OBJECT
 public:
     GLWidget(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
     void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);
 private:
     GLUquadricObj *pobj;     
     QPoint lastPos;
     GLfloat rotationX, rotationY, rotationZ;
 };
 #endif

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Main windows cpp file...

#include <QtGui>
 #include <QtOpenGL>
 #include <math.h>
 #include "glwidget1.h"
 GLWidget::GLWidget(QWidget *parent)
     : QGLWidget(parent)
 { }
 void GLWidget::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget::paintGL()
 {     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW); 
     glLoadIdentity();    
     glTranslatef(0.0, 0.0, -15.0); 
     glRotatef(rotationX, 1.0, 0.0, 0.0); 
     glRotatef(rotationY, 0.0, 1.0, 0.0); 
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
         pobj = gluNewQuadric();
         gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
         qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 3, 30, 30); }
 void GLWidget::resizeGL(int width, int height)
 {     glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    GLfloat x = GLfloat(width) / height; 
    glFrustum(-x, +x, -1.0, +1.0, 4.0, 20.0); 
    glMatrixMode(GL_MODELVIEW);  }
void GLWidget::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos(); }
 void GLWidget::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width(); 
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height(); 
    if (event->buttons() & Qt::LeftButton) { 
        rotationX += 180 * dy;
        rotationY += 180 * dx; 
        updateGL(); 
    } else if (event->buttons() & Qt::RightButton) { 
        rotationX += 180 * dy; 
        rotationZ += 180 * dx; 
        updateGL();     } 
    lastPos = event->pos();  }

#include <QtGui>
 #include <QtOpenGL>
 #include <math.h>
 #include "glwidget1.h"
 GLWidget::GLWidget(QWidget *parent)
     : QGLWidget(parent)
 { }
 void GLWidget::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget::paintGL()
 {     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW); 
     glLoadIdentity();    
     glTranslatef(0.0, 0.0, -15.0); 
     glRotatef(rotationX, 1.0, 0.0, 0.0); 
     glRotatef(rotationY, 0.0, 1.0, 0.0); 
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
         pobj = gluNewQuadric();
         gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
         qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 3, 30, 30); }
 void GLWidget::resizeGL(int width, int height)
 {     glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    GLfloat x = GLfloat(width) / height; 
    glFrustum(-x, +x, -1.0, +1.0, 4.0, 20.0); 
    glMatrixMode(GL_MODELVIEW);  }
void GLWidget::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos(); }
 void GLWidget::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width(); 
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height(); 
    if (event->buttons() & Qt::LeftButton) { 
        rotationX += 180 * dy;
        rotationY += 180 * dx; 
        updateGL(); 
    } else if (event->buttons() & Qt::RightButton) { 
        rotationX += 180 * dy; 
        rotationZ += 180 * dx; 
        updateGL();     } 
    lastPos = event->pos();  }

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this code is for the other window............. //glwidget2.cpp file...

#include "glwidget2.h"
#include <QtGui>
#include <QtOpenGL>
 #include <math.h>
GLWidget_fin::GLWidget_fin(QWidget *parent)
     : QGLWidget(parent)
 { }
void GLWidget_fin::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget_fin::paintGL()
 {     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
     glTranslatef(0.0, 0.0, -15.0);
     glRotatef(rotationX, 1.0, 0.0, 0.0);
     glRotatef(rotationY, 0.0, 1.0, 0.0);
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
     pobj = gluNewQuadric();
     gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
     qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 1, 30, 30); }
 void GLWidget_fin::resizeGL(int width, int height)
 {    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    GLfloat x = GLfloat(width) / height;
    glFrustum(-x, +x, -1.0, +1.0, 10.0, 40.0);
    glMatrixMode(GL_MODELVIEW); }
/*void GLWidget_fin::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos(); }
 void GLWidget_fin::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width();
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height();
    if (event->buttons() & Qt::LeftButton) {
        rotationX += 180 * dy;
        rotationY += 180 * dx;
        updateGL();
    } else if (event->buttons() & Qt::RightButton) {
        rotationX += 180 * dy;
        rotationZ += 180 * dx;
        updateGL();    }
    lastPos = event->pos(); }*/

#include "glwidget2.h"
#include <QtGui>
#include <QtOpenGL>
 #include <math.h>
GLWidget_fin::GLWidget_fin(QWidget *parent)
     : QGLWidget(parent)
 { }
void GLWidget_fin::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget_fin::paintGL()
 {     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
     glTranslatef(0.0, 0.0, -15.0);
     glRotatef(rotationX, 1.0, 0.0, 0.0);
     glRotatef(rotationY, 0.0, 1.0, 0.0);
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
     pobj = gluNewQuadric();
     gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
     qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 1, 30, 30); }
 void GLWidget_fin::resizeGL(int width, int height)
 {    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    GLfloat x = GLfloat(width) / height;
    glFrustum(-x, +x, -1.0, +1.0, 10.0, 40.0);
    glMatrixMode(GL_MODELVIEW); }
/*void GLWidget_fin::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos(); }
 void GLWidget_fin::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width();
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height();
    if (event->buttons() & Qt::LeftButton) {
        rotationX += 180 * dy;
        rotationY += 180 * dx;
        updateGL();
    } else if (event->buttons() & Qt::RightButton) {
        rotationX += 180 * dy;
        rotationZ += 180 * dx;
        updateGL();    }
    lastPos = event->pos(); }*/

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glwidget2.h header file...

#ifndef GLWIDGET2_H
#define GLWIDGET2_H
#include <QGLWidget>
 class GLWidget_fin : public QGLWidget
 {     Q_OBJECT
 public:
     GLWidget_fin(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
    /* void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);*/
 private:
    GLUquadricObj *pobj;
    QPoint lastPos;
    GLfloat rotationX, rotationY, rotationZ; };
#endif // GLWIDGET2_H

#ifndef GLWIDGET2_H
#define GLWIDGET2_H
#include <QGLWidget>
 class GLWidget_fin : public QGLWidget
 {     Q_OBJECT
 public:
     GLWidget_fin(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
    /* void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);*/
 private:
    GLUquadricObj *pobj;
    QPoint lastPos;
    GLfloat rotationX, rotationY, rotationZ; };
#endif // GLWIDGET2_H

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glwidget3.h header file for the third GLWidget

#ifndef GLWIDGET3_H
#define GLWIDGET3_H
#include <QGLWidget>
 class GLWidget_rear : public QGLWidget
 {      Q_OBJECT
 public:
     GLWidget_rear(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
     /*void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);*/
 private:
     GLUquadricObj *pobj;
     QPoint lastPos;
     GLfloat rotationX, rotationY, rotationZ; };
#endif // GLWIDGET3_H

#ifndef GLWIDGET3_H
#define GLWIDGET3_H
#include <QGLWidget>
 class GLWidget_rear : public QGLWidget
 {      Q_OBJECT
 public:
     GLWidget_rear(QWidget *parent = 0);
 protected:
     void initializeGL();
     void paintGL();
     void resizeGL(int width, int height);
     /*void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);*/
 private:
     GLUquadricObj *pobj;
     QPoint lastPos;
     GLfloat rotationX, rotationY, rotationZ; };
#endif // GLWIDGET3_H

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glwidget3.cpp file ..... third widgets cpp file...

#include "glwidget3.h"
#include <QtGui>
#include <QtOpenGL>
 #include <math.h>
 GLWidget_rear::GLWidget_rear(QWidget *parent)
     : QGLWidget(parent)
 { }
void GLWidget_rear::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget_rear::paintGL()
 {      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
     glTranslatef(0.0, 0.0, -15.0);
     glRotatef(rotationX, 1.0, 0.0, 0.0);
     glRotatef(rotationY, 0.0, 1.0, 0.0);
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
     pobj = gluNewQuadric();
     gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
     qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 3, 30, 30); }
 void GLWidget_rear::resizeGL(int width, int height)
 {    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    GLfloat x = GLfloat(width) / height;
    glFrustum(-x, +x, -1.0, +1.0, 4.0, 10.0);
    glMatrixMode(GL_MODELVIEW); }
/*void GLWidget_rear::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos();  }
 void GLWidget_rear::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width();
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height();
    if (event->buttons() & Qt::LeftButton) {
        rotationX += 180 * dy;
        rotationY += 180 * dx;
        updateGL();
    } else if (event->buttons() & Qt::RightButton) {
        rotationX += 180 * dy;
        rotationZ += 180 * dx;
        updateGL();    }
    lastPos = event->pos();
 }*/

#include "glwidget3.h"
#include <QtGui>
#include <QtOpenGL>
 #include <math.h>
 GLWidget_rear::GLWidget_rear(QWidget *parent)
     : QGLWidget(parent)
 { }
void GLWidget_rear::initializeGL()
 {     qglClearColor(Qt::gray);
     glShadeModel(GL_SMOOTH);
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE); }
 void GLWidget_rear::paintGL()
 {      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
     glTranslatef(0.0, 0.0, -15.0);
     glRotatef(rotationX, 1.0, 0.0, 0.0);
     glRotatef(rotationY, 0.0, 1.0, 0.0);
     glRotatef(rotationZ, 0.0, 0.0, 1.0);
     pobj = gluNewQuadric();
     gluQuadricDrawStyle(pobj, GLU_LINE);
     gluQuadricNormals(pobj, GLU_SMOOTH);
     qglColor(Qt::red);
     gluCylinder(pobj, 1, 1, 3, 30, 30); }
 void GLWidget_rear::resizeGL(int width, int height)
 {    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    GLfloat x = GLfloat(width) / height;
    glFrustum(-x, +x, -1.0, +1.0, 4.0, 10.0);
    glMatrixMode(GL_MODELVIEW); }
/*void GLWidget_rear::mousePressEvent(QMouseEvent *event)
 {     lastPos = event->pos();  }
 void GLWidget_rear::mouseMoveEvent(QMouseEvent *event)
 {    GLfloat dx = GLfloat(event->x() - lastPos.x()) / width();
    GLfloat dy = GLfloat(event->y() - lastPos.y()) / height();
    if (event->buttons() & Qt::LeftButton) {
        rotationX += 180 * dy;
        rotationY += 180 * dx;
        updateGL();
    } else if (event->buttons() & Qt::RightButton) {
        rotationX += 180 * dy;
        rotationZ += 180 * dx;
        updateGL();    }
    lastPos = event->pos();
 }*/

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main.cpp file for the program...

#include <QApplication>
#include <QDesktopWidget>
 #include "window.h"
 int main(int argc, char *argv[])
 {     QApplication app(argc, argv);
     Window window;
     window.show();
     return app.exec(); }

#include <QApplication>
#include <QDesktopWidget>
 #include "window.h"
 int main(int argc, char *argv[])
 {     QApplication app(argc, argv);
     Window window;
     window.show();
     return app.exec(); }

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this 3 widgets are put in together into a window widgets whos code is
window.h

#ifndef WINDOW_H
 #define WINDOW_H
 #include <QWidget>
 #include <QDialog>
 class GLWidget;
 class Window : public QWidget
 {     Q_OBJECT
 public:
     Window();
 private:
          GLWidget *glWidget1,              //glWidget1 -> main Design Widget
              *glWidget2,              //glWidget2 -> Fin Design Widget
              *glWidget3 ;             //glWidget3 -> rear View Design Widget */
  };
 #endif

#ifndef WINDOW_H
 #define WINDOW_H
 #include <QWidget>
 #include <QDialog>
 class GLWidget;
 class Window : public QWidget
 {     Q_OBJECT
 public:
     Window();
 private:
          GLWidget *glWidget1,              //glWidget1 -> main Design Widget
              *glWidget2,              //glWidget2 -> Fin Design Widget
              *glWidget3 ;             //glWidget3 -> rear View Design Widget */
  };
 #endif

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and the .cpp file of the main window is

#include <QtGui>
 #include "glwidget1.h"
 #include "glwidget2.h"
 #include "glwidget3.h"
 #include "window.h"
 Window::Window()
 {     glWidget1 = new GLWidget;
     glWidget2 = new GLWidget;
     glWidget3 = new GLWidget;
          QVBoxLayout *vLayout = new QVBoxLayout;
     vLayout->addWidget(glWidget2);
     vLayout->addWidget(glWidget3);
     QHBoxLayout *hLayout = new QHBoxLayout;
     hLayout->addWidget(glWidget1);
     hLayout->addLayout(vLayout);
     setLayout(hLayout);
     QSizePolicy sizePolicy1(QSizePolicy::Expanding, QSizePolicy::Expanding);
     glWidget1->setSizePolicy(sizePolicy1);
     QSizePolicy sizePolicy2(QSizePolicy::Fixed, QSizePolicy::Fixed);
     glWidget2->setSizePolicy(sizePolicy2);
     QSizePolicy sizePolicy3(QSizePolicy::Fixed, QSizePolicy::Fixed);
     glWidget2->setSizePolicy(sizePolicy3);
     glWidget1->setMaximumSize(QSize(1000, 1000));
     glWidget1->setMinimumSize(QSize(800, 800));
     glWidget2->setMaximumSize(QSize(400,400));
     glWidget2->setMinimumSize(QSize(400,400));
     glWidget2->resize(400,400);
     glWidget3->setMaximumSize(QSize(400,400));
     glWidget3->setMinimumSize(QSize(400,400));
          setWindowTitle(tr("Hello GL")); }

#include <QtGui>
 #include "glwidget1.h"
 #include "glwidget2.h"
 #include "glwidget3.h"
 #include "window.h"
 Window::Window()
 {     glWidget1 = new GLWidget;
     glWidget2 = new GLWidget;
     glWidget3 = new GLWidget;
          QVBoxLayout *vLayout = new QVBoxLayout;
     vLayout->addWidget(glWidget2);
     vLayout->addWidget(glWidget3);
     QHBoxLayout *hLayout = new QHBoxLayout;
     hLayout->addWidget(glWidget1);
     hLayout->addLayout(vLayout);
     setLayout(hLayout);
     QSizePolicy sizePolicy1(QSizePolicy::Expanding, QSizePolicy::Expanding);
     glWidget1->setSizePolicy(sizePolicy1);
     QSizePolicy sizePolicy2(QSizePolicy::Fixed, QSizePolicy::Fixed);
     glWidget2->setSizePolicy(sizePolicy2);
     QSizePolicy sizePolicy3(QSizePolicy::Fixed, QSizePolicy::Fixed);
     glWidget2->setSizePolicy(sizePolicy3);
     glWidget1->setMaximumSize(QSize(1000, 1000));
     glWidget1->setMinimumSize(QSize(800, 800));
     glWidget2->setMaximumSize(QSize(400,400));
     glWidget2->setMinimumSize(QSize(400,400));
     glWidget2->resize(400,400);
     glWidget3->setMaximumSize(QSize(400,400));
     glWidget3->setMinimumSize(QSize(400,400));
          setWindowTitle(tr("Hello GL")); }

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this the pro file that was generated to which I have added QT += opengl for running the opengl program...

######################################################################
# Automatically generated by qmake (2.01a) Wed Feb 11 14:50:13 2009
######################################################################
TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
QT += opengl
# Input
HEADERS += glwidget1.h glwidget2.h glwidget3.h window.h
SOURCES += glwidget1.cpp glwidget2.cpp glwidget3.cpp main.cpp window.cpp

######################################################################
# Automatically generated by qmake (2.01a) Wed Feb 11 14:50:13 2009
######################################################################
TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
QT += opengl
# Input
HEADERS += glwidget1.h glwidget2.h glwidget3.h window.h
SOURCES += glwidget1.cpp glwidget2.cpp glwidget3.cpp main.cpp window.cpp

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[john_god]

I've notice some issues in your code, you define 3 classes, GLWidget, GLWidget_fin, GLWidget_rear, but the 3 variables glWidget1, glWidget2, and glWidget3 are all from
GLWidget type.
Also don't see the point of declaring 3 classes with the same code.
I compile the code of your program and the widget doesnt fit in my screen, is your intention to do the widget with fixed dimensions ?
As far only one cilinder being show, sorry I also dond't know
Gurus where are you ?

[manmohan]

Thanks dude for checking, but I have declared the same class because once I get the display then I will be changing the display of the widgets in a different way.....


Any body please help...............

[john_god]

Also you may checkout in the Qt Assistant the "GLWidget" and read it. I think there's a issue with the widget's OpenGL rendering context, witch has to be made current with the makeCurrent() function. This would explain why only the first cilinder is being draw.

[manmohan]

Thanks dude I have tried that too but there was no improvement.....

Please help me yar....

this will help me in developing a g8t app....

Thanks for the help.....

[manmohan]

Hey dude is there any forum from where I could get help regarding this program please let me know......

Thank's
Mohan