How to create cube using opengl in qt

mahesh

hi, some one please help me. i want to create a cube(3D Object) with this following code but i am getting only single rectItem(backside).this is my glwidget item code is ther any wrong in the code?
@
#include "glwidget.h"

GLWidget::GLWidget(QWidget *parent) :
QGLWidget(parent)
{
}

void GLWidget::initializeGL()
{
glClearColor(1,1,1,1);
}

void GLWidget::paintGL()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef(0.0f,0.0f,0.0f);

glBegin(GL_QUADS);

   glColor3f(0.0f,1.0f,0.0f);          // Set The Color To Green
   glVertex3f( 1.0f, 1.0f,-1.0f);          // Top Right Of The Quad (Top)
   glVertex3f(-1.0f, 1.0f,-1.0f);          // Top Left Of The Quad (Top)
   glVertex3f(-1.0f, 1.0f, 1.0f);          // Bottom Left Of The Quad (Top)
   glVertex3f( 1.0f, 1.0f, 1.0f);          // Bottom Right Of The Quad (Top)


   glColor3f(1.0f,0.5f,0.0f);          // Set The Color To Orange
   glVertex3f( 1.0f,-1.0f, 1.0f);          // Top Right Of The Quad (Bottom)
   glVertex3f(-1.0f,-1.0f, 1.0f);          // Top Left Of The Quad (Bottom)
   glVertex3f(-1.0f,-1.0f,-1.0f);          // Bottom Left Of The Quad (Bottom)
   glVertex3f( 1.0f,-1.0f,-1.0f);          // Bottom Right Of The Quad (Bottom)

   glColor3f(1.0f,0.0f,0.0f);          // Set The Color To Red
   glVertex3f( 1.0f, 1.0f, 1.0f);          // Top Right Of The Quad (Front)
   glVertex3f(-1.0f, 1.0f, 1.0f);          // Top Left Of The Quad (Front)
   glVertex3f(-1.0f,-1.0f, 1.0f);          // Bottom Left Of The Quad (Front)
   glVertex3f( 1.0f,-1.0f, 1.0f);          // Bottom Right Of The Quad (Front)

   glColor3f (1.0f,1.0f,0.0f);          // Set The Color To Yellow
   glVertex3f( 1.0f,-1.0f,-1.0f);          // Bottom Left Of The Quad (Back)
   glVertex3f(-1.0f,-1.0f,-1.0f);          // Bottom Right Of The Quad (Back)
   glVertex3f(-1.0f, 1.0f,-1.0f);          // Top Right Of The Quad (Back)
   glVertex3f( 1.0f, 1.0f,-1.0f);          // Top Left Of The Quad (Back)

   glColor3f(0.0f,0.0f,1.0f);          // Set The Color To Blue
   glVertex3f(-1.0f, 1.0f, 1.0f);          // Top Right Of The Quad (Left)
   glVertex3f(-1.0f, 1.0f,-1.0f);          // Top Left Of The Quad (Left)
   glVertex3f(-1.0f,-1.0f,-1.0f);          // Bottom Left Of The Quad (Left)
   glVertex3f(-1.0f,-1.0f, 1.0f);          // Bottom Right Of The Quad (Left)

   glColor3f(1.0f,0.0f,1.0f);          // Set The Color To Violet
   glVertex3f( 1.0f, 1.0f,-1.0f);          // Top Right Of The Quad (Right)
   glVertex3f( 1.0f, 1.0f, 1.0f);          // Top Left Of The Quad (Right)
   glVertex3f( 1.0f,-1.0f, 1.0f);          // Bottom Left Of The Quad (Right)
   glVertex3f( 1.0f,-1.0f,-1.0f);          // Bottom Right Of The Quad (Right)


 glEnd();

}

void GLWidget::resizeGL(int w, int h)
{
}
@

john_god

You have to define a viewport in the resizeGL() method

one example

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void GLWidget::resizeGL(int w, int h)
{
double Aspect;

// Prevent a divide by zero, when window is too short
// (you cant make a window of zero width)
if(h == 0)//altura
h = 1;

    // Set the viewport to be the entire window
glViewport(0, 0, w, h);


Aspect=(double)w/(double)h;

//Reset projection matrix stack
glMatrixMode(GL_PROJECTION);
// Reset the coordinate system before modifying
glLoadIdentity();

// gluPerspective(45.0f,Aspect, 1.0, 425.0);

 double Range = 10;

if (w <= h)
    glOrtho(-(Range),Range,-Range/Aspect,Range/Aspect,-(Range*2),Range*2);
else
    glOrtho(-(Range*Aspect),Range*Aspect,-Range,Range,-(Range*2),Range*2);

glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

}@

Note you are using the deprecate OpenGL fixed pipeline. There's a example of a cube with programable shaders for symbian, somewhere in Nokia forum I believe, can´t remember right now.

mahesh

hi some one please tell me i just created a cube in 3d.
For small values of x,y co ordinates it is working fine for bigger values it is not showing cube. it is adding to the scene but i am unable to move my view to those co ordinates."graphicsview having fitInView .is there any similar funtion for QGLWidget"
@
GLWidget::GLWidget(QWidget *parent) :
QGLWidget(parent)
{
}
void GLWidget::initializeGL()
{
glClearColor(1,1,1,1);
glShadeModel(GL_FLAT);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
}

void GLWidget::paintGL()
{

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

glBegin(GL_QUADS);

 glEnd();

}
void GLWidget::resizeGL(int w, int h)
{

   double Aspect;
   if(h == 0)
        h = 1;
    glViewport(0, 0, w, h);
    Aspect=(double)w/(double)h;
            glMatrixMode(GL_PROJECTION);
           glLoadIdentity();
           double Range = 10;
    if (w <= h)
        glOrtho(-(Range),Range,-Range/Aspect,Range/Aspect,-(Range*2),Range*2);
    else
        glOrtho(-(Range*Aspect),Range*Aspect,-Range,Range,-(Range*2),Range*2);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

}

@