[Moved]Not able to use updateGL()

mandal.chintangmail.com

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&#40;&#41;;

}

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

#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;
};

};
@

DeVeL-2010

Hi chintu,

there are two problems.
Change resizeGL() to:
@
void resizeGL(int Height, int Width) {
glViewport(0, 0, Width, Height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-200, 200, -200, 200, -1, 1);
glMatrixMode(GL_MODELVIEW);
};
@
OpenGL need a box for the scenario (glOrtho) and viewport was wrong.

In paintGL(), your lines for drawing are wrong, change like this:
@
glVertex2f(Pt[counter+1].getsx(),Pt[counter+1].getsy());
@
As hint: you need counter+i in x and y coordinate!