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calling the same calss/method 2 times with different parameters

rb0306 (2)
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All,

sorry for asking basic question, couldn't able to figure out how to do it. I am calling OpenGL class GlobJ to paint lines,circles..etc. I need to call the same class again to paint Sine wave. here is my code.

Code to draw Lines/circles..etc. is as below.

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  #include <QtGui/QtGui>
#include <QtOpenGL/QtOpenGL>
#include <math.h>
#include "globj.h"

GLobj::GLobj(QWidget *parent)
    : QGLWidget(parent)
{

}

GLobj::~GLobj()
{

}

//Initialize the GL settings
void GLobj::initializeGL()
{
    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClearDepth(5.0f);
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LEQUAL);
    glPointSize(2.0);
    glLineWidth(4.0);
    
}

//Set up the viewport based on the screen dimentions
//Function is called implicitly by initializeGL and when screen is resized
void GLobj::resizeGL( int w, int h )
{
    //algorithm to keep scene "square" (preserve aspect ratio)
    //even if screen is streached
    if(w>h)
        glViewport((w-h)/2, 0, h, h);
    else
        glViewport(0, (h-w)/2, w, w);

    //setup the projection and switch to model view for transformations
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-1, 1, -1, 1, -1, 1);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    

    //implicit call to paintGL after resized
}

//Paints the GL scene
void GLobj::paintGL()
{
    glClear (GL_COLOR_BUFFER_BIT);
    glClear(GL_DEPTH_BUFFER_BIT);
    
    glBegin(GL_POINTS);
    
    glColor3f (1.0, 1.0, 1.0);
     glVertex2f(-0.95,0.85);
    glEnd();

   glBegin(GL_LINES);
   glColor3f (1.0, 0.0, 0.0);
   glVertex2f(-0.75,0.65);
   glVertex2f(-0.75,0.25);
    glEnd();

   glBegin(GL_TRIANGLES);
   glColor3f (1.0, 0.0,1.0);
   glVertex2f(-0.65,0.0);
   glVertex2f(-0.45,0.0);
   glVertex2f(-0.55,0.5);
    glEnd();

 glBegin(GL_QUADS);
 glColor3f (0.0, 1.0,1.0);
 glVertex2f(0.1, 0.1);
 glVertex2f(0.3,0.1);
 glVertex2f(0.3,0.3);
 glVertex2f(0.1,0.3);
 glEnd();


 glBegin(GL_QUADS);
 glColor3f (0.0, 0.0,1.0);
 glVertex2f(0.4, 0.1);
 glVertex2f(0.9, 0.1);
 glVertex2f(0.9, 0.3);
 glVertex2f(0.4, 0.3);
 glEnd();

 glBegin(GL_POLYGON);
 glColor3f (1.0, 1.0,0.0);
 glVertex2f(0.1, 0.6);
 glVertex2f(0.2, 0.4);
 glVertex2f(0.4, 0.4);
 glVertex2f(0.5, 0.6);
 glVertex2f(0.3, 0.8);
 glEnd();

 glBegin(GL_POLYGON);
 glColor3f (0.5, 1.0,1.0);
 glVertex2f(0.6, 0.6);
 glVertex2f(0.7, 0.5);
 glVertex2f(0.8, 0.5);
 glVertex2f(0.9, 0.6);
 glVertex2f(0.8, 0.7);
 glVertex2f(0.7, 0.7);
 glEnd();

 glBegin(GL_POLYGON);
 glColor3f (0.5, 0.5,1.0);
 glVertex2f(-0.1, -0.2);
 glVertex2f(-0.2, -0.1);
 glVertex2f(-0.3, -0.1);
 glVertex2f(-0.4, -0.2);
 glVertex2f(-0.4, -0.3);
 glVertex2f(-0.25, -0.45);
 glVertex2f(-0.1, -0.3);
 glEnd();

 glBegin(GL_QUADS);
 glColor3f (0.5, 0.5,0.5);
 glVertex2f(0.1, -0.2);
 glVertex2f(0.3, -0.2);
 glVertex2f(0.3, -0.4);
 glVertex2f(0.1, -0.4);
 glEnd();

 glBegin(GL_QUADS);
 glColor3f (1.0, 0.5,1.0);
 glVertex2f(0.3, -0.2);
 glVertex2f(0.35, -0.3);
 glVertex2f(0.35, -0.5);
 glVertex2f(0.3, -0.4);
 glEnd();

 glBegin(GL_QUADS);
 glColor3f (1.0, 1.0,0.5);
 glVertex2f(0.1, -0.4);
 glVertex2f(0.3, -0.4);
 glVertex2f(0.35, -0.5);
 glVertex2f(0.15, -0.5);
 glEnd();

    glFlush ();
}


I am calling above program in my add widget program as below:

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GLobj *globj = new GLobj(this);
QHBoxLayout *mainLayout3 = new QHBoxLayout(this);
    mainLayout3->addWidget(globj);

      QWidget *newWidget3 = new QWidget(this);
      newWidget3->setLayout(mainLayout3);

      dwidget3->setWidget(newWidget3);

      addDockWidget(Qt::RightDockWidgetArea, dwidget3);


until here everything is working fine. Now i wrote another program to draw Sine wave.

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  #include <QtGui/QtGui>
#include <QtOpenGL/QtOpenGL>
#include <math.h>
#include "globj.h"
#include <iostream>

using namespace std;

GLobj::GLobj(QWidget *parent)
    : QGLWidget(parent)
{

}

GLobj::~GLobj()
{

}

//Initialize the GL settings
void GLobj::initializeGL()
{
    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClearDepth(1.0f);
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LEQUAL);
    glPointSize(2.0);
    glLineWidth(1.0);
    
}

//Set up the viewport based on the screen dimentions
//Function is called implicitly by initializeGL and when screen is resized
void GLobj::resizeGL( int w, int h )
{
    //algorithm to keep scene "square" (preserve aspect ratio)
    //even if screen is streached
    if(w>h)
        glViewport((w-h)/2, 0, h, h);
    else
        glViewport(0, (h-w)/2, w, w);

    //setup the projection and switch to model view for transformations
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-1, 1, -1, 1, -1, 1);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    

    //implicit call to paintGL after resized
}

//Paints the GL scene
void GLobj::paintGL()
{
    glClear (GL_COLOR_BUFFER_BIT);
    glClear(GL_DEPTH_BUFFER_BIT);

glBegin(GL_LINES);
double amp=1;
double freq = 4;
double t=0.0;
for (double x=-1.0; x<=1; x+=0.001)
{
double y = amp * cos(2 * 3.14 * freq * x );
glVertex2f(x, y);
t+=10.0;
}
glEnd();

glBegin(GL_LINES);
double amp2=1;
double freq2 = 4;
double t2=0.0;
for (double x2=-0.999; x2<=1; x2+=0.001)
{
double y2 = amp2 * cos(2 * 3.14 * freq2 * x2 );
glVertex2f(x2, y2);
t+=10.0;
}
glEnd();

    glFlush ();
}


I need to call this sine wave in my add widget program, this one is different from lines/circles widget above. this is where i am getting trouble.


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  dwidget3 = new QDockWidget(tr("Sine Wave"), this);
    
    GLobj2 *globj2 = new GLobj2(this);
    QHBoxLayout *mainLayout4 = new QHBoxLayout(this);
    mainLayout3->addWidget(globj2);

      QWidget *newWidget4 = new QWidget(this);
      newWidget4->setLayout(mainLayout4);

      dwidget3->setWidget(newWidget4);

      dwidget3->show();
      addDockWidget(Qt::RightDockWidgetArea, dwidget3);


Thanks,
Ravi
keskiverto (10402)
What trouble, apart from using class GLobj2 instead of class GLobj?


You could have single GLobj type, if it had a functor that you change as needed.
rb0306 (2)
keskiverto,

Thank you very much for your help. That worked. I think somewhere i missed to change it to GlobJ2 in my GlobJ2 file.

Ravi Bavanari
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