Not able to use updateGL()

[chintu]

I am giving the whole code of this small program which I have written. It is very necessary to use the loop as my data is supposed to kept in the loops.
I do not want to use the qTimer() function ....
There is no output of the program. I do not know where do I keep the updateGL().
The program is only supposed to draw some squares in two different colors ....
I am using Netbeans IDE.
The GUI is shown but only with a black screen with the code.
Give me some advise on where I should make changes ......

Please help .....
;( ;( ;( ;(

#include <QtGui/QApplication>
#include <QtOpenGL/QGLWidget>
#include <QtGui/QColor>
#include <QtOpenGL/qgl.h>
#include <iostream>
#include <time.h>
#include "Quad.h"
 
int main(int argc, char *argv[]) {
    // initialize resources, if needed
    // Q_INIT_RESOURCE(resfile);
 
    QApplication app(argc, argv);
 
    // create and show your widgets here
    Quad *w = new Quad();
    w->show();
    return app.exec();
}
 
// =================================================================================================
 
#include "Point.h"
class Quad : public QGLWidget {
    Q_OBJECT
 
private:
    Point *Pt;
    int total_objects;
protected:
 
    void InitializeGL() {
        // Set the way we want things to look
        glShadeModel(GL_FLAT);
        glEnable(GL_DEPTH_TEST);
        glEnable(GL_CULL_FACE);
    };
 
    void resizeGL(int Height, int Width) {
        glViewport(Width, Height, 0, 0);
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        glMatrixMode(GL_MODELVIEW);
    };
 
    void paintGL() {
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glLoadIdentity();
        int counter;
        for(counter=0;counter<100;counter+=4){
            if(Pt[counter].getcol()==true){
                qglColor(Qt::red);
                glBegin(GL_QUADS);
                glVertex2f(Pt[counter].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+1].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+2].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+3].getsx(),Pt[counter].getsy());
                glEnd();
            }else{
                qglColor(Qt::white);
                glBegin(GL_QUADS);
                glVertex2f(Pt[counter].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+1].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+2].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+3].getsx(),Pt[counter].getsy());
                glEnd();
            }
        }
//        updateGL();
    };
 
public:
 
    Quad(QWidget *parent = 0) {
        srand(time(NULL));
        int counter;
        total_objects = 100;
        Pt = new Point[total_objects]();
        for (counter = 0; counter < 100; counter++) {
            Pt[counter].init((float) (rand() % 100), (float) (rand() % 100), ((rand() % 2) == 0 ? true : false));
        }
    };
};
 
//===============================================================================================================================
 
class Point {
private:
    float s_x;
    float s_y;
    bool col;
public:
 
    Point(float sx, float sy, bool co) {
        s_x = sx;
        s_y = sy;
        col = co;
    };
 
    Point() {};
 
    void init(float sx, float sy, bool co) {
        s_x = sx;
        s_y = sy;
        col = co;
    };
 
    float getsx() {
        return s_x;
    };
 
    float getsy() {
        return s_y;
    };
 
    bool getcol() {
        return col;
    };
};

#include <QtGui/QApplication>
#include <QtOpenGL/QGLWidget>
#include <QtGui/QColor>
#include <QtOpenGL/qgl.h>
#include <iostream>
#include <time.h>
#include "Quad.h"

int main(int argc, char *argv[]) {
    // initialize resources, if needed
    // Q_INIT_RESOURCE(resfile);

    QApplication app(argc, argv);

    // create and show your widgets here
    Quad *w = new Quad();
    w->show();
    return app.exec();
}

// =================================================================================================

#include "Point.h"
class Quad : public QGLWidget {
    Q_OBJECT

private:
    Point *Pt;
    int total_objects;
protected:

    void InitializeGL() {
        // Set the way we want things to look
        glShadeModel(GL_FLAT);
        glEnable(GL_DEPTH_TEST);
        glEnable(GL_CULL_FACE);
    };

    void resizeGL(int Height, int Width) {
        glViewport(Width, Height, 0, 0);
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        glMatrixMode(GL_MODELVIEW);
    };

    void paintGL() {
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glLoadIdentity();
        int counter;
        for(counter=0;counter<100;counter+=4){
            if(Pt[counter].getcol()==true){
                qglColor(Qt::red);
                glBegin(GL_QUADS);
                glVertex2f(Pt[counter].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+1].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+2].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+3].getsx(),Pt[counter].getsy());
                glEnd();
            }else{
                qglColor(Qt::white);
                glBegin(GL_QUADS);
                glVertex2f(Pt[counter].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+1].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+2].getsx(),Pt[counter].getsy());
                glVertex2f(Pt[counter+3].getsx(),Pt[counter].getsy());
                glEnd();
            }
        }
//        updateGL();
    };
    
public:

    Quad(QWidget *parent = 0) {
        srand(time(NULL));
        int counter;
        total_objects = 100;
        Pt = new Point[total_objects]();
        for (counter = 0; counter < 100; counter++) {
            Pt[counter].init((float) (rand() % 100), (float) (rand() % 100), ((rand() % 2) == 0 ? true : false));
        }
    };
};

//===============================================================================================================================

class Point {
private:
    float s_x;
    float s_y;
    bool col;
public:

    Point(float sx, float sy, bool co) {
        s_x = sx;
        s_y = sy;
        col = co;
    };

    Point() {};

    void init(float sx, float sy, bool co) {
        s_x = sx;
        s_y = sy;
        col = co;
    };

    float getsx() {
        return s_x;
    };

    float getsy() {
        return s_y;
    };

    bool getcol() {
        return col;
    };
};

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Thanks in advance for the help .....

[bahbah30]

try this in InitializeGL():

QTimer *timer = new QTimer();    
timer->start(1); //time in ms, here 1 ms
connect(timer ,SIGNAL(timeout()),this,SLOT(updateGL()));

QTimer *timer = new QTimer();    
timer->start(1); //time in ms, here 1 ms
connect(timer ,SIGNAL(timeout()),this,SLOT(updateGL()));

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[wysota]

The method should be called initializeGL and not InitializeGL. Furthermore resizeGL() has width and height variables swapped. Call to glViewport() also seems invalid. And calling updateGL() with a timer is not required.