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Hi @patofis!

You can easily render a Texture in a opengl window using OpenCV! Here is a sample code to attach a Texture to a Cube. I will leave the rest of the shapes for you. since you can get enough Opengl code samples for that!

#include <windows.h>
#include <stdio.h>
#include <glut.h>

#include "opencv2/core/core.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <strstream>
#include <functional>

using namespace std;
using namespace cv;

GLuint TextureIdx[1]; //the array for our TextureIdx
Mat mSource_Bgr;
GLfloat angle = 45.0;
//The IplImage to OpenGl TextureIdx function
int UploadTexture(Mat image, GLuint &TextureIdx) 
{
    if (image.empty()) 
        return -1;
    glGenTextures(1, &TextureIdx);
    glBindTexture( GL_TEXTURE_2D, TextureIdx); //bind the TextureIdx to it's array
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, image.cols, image.rows,0, GL_BGR_EXT, GL_UNSIGNED_BYTE, image.data);
    return 0;
}
void plane (void) 
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
    glLoadIdentity();                                   // Reset The View
    glTranslatef(0.0f,.0f,-5.0f);

    glRotatef(angle,1.0f,1.0f,0.0f);
    glBindTexture( GL_TEXTURE_2D, TextureIdx[0]); //unbind the TextureIdx

    glBegin(GL_QUADS);
        // Front Face
        glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
        // Back Face
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        // Top Face
        glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
        // Bottom Face
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
        // Right face
        glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
        glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
        // Left Face
        glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
        glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
        glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
        glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
    glEnd();


    glBindTexture( GL_TEXTURE_2D, 0); //unbind the TextureIdx
}
void display (void) 
{
    glClearColor (0.0,0.0,0.0,1.0);
    glClear (GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

    plane();
    glutSwapBuffers();
}
void FreeTexture( GLuint TextureIdx )
{
    glDeleteTextures( 1, &TextureIdx );
}
void reshape (int w, int h) 
{
    glViewport (0, 0, (GLsizei)w, (GLsizei)h);
    glMatrixMode (GL_PROJECTION);
    glLoadIdentity ();
    gluPerspective (60, (GLfloat)w / (GLfloat)h, 1.0, 100.0);
    glMatrixMode (GL_MODELVIEW);
}
int main (int argc, char **argv)
{
    glutInit (&argc, argv);
    glutInitDisplayMode (GLUT_RGBA | GLUT_DOUBLE);
    glutInitWindowSize (500, 500);
    glutInitWindowPosition (100, 100);
    glutCreateWindow ("A basic OpenGL Window");
    glEnable(GL_TEXTURE_2D);                        // Enable Texture Mapping ( NEW )
    glShadeModel(GL_SMOOTH);                        // Enable Smooth Shading
    glClearColor(0.0f, 0.0f, 0.0f, 0.5f);           // Black Background
    glClearDepth(1.0f);                             // Depth Buffer Setup
    glEnable(GL_DEPTH_TEST);                        // Enables Depth Testing
    glDepthFunc(GL_LEQUAL);                         // The Type Of Depth Testing To Do
    glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);          // Really Nice Perspective 

    glutDisplayFunc (display);
    glutIdleFunc (display);
    glutReshapeFunc (reshape);

    mSource_Bgr=imread("Lena.png",1);       //The load iplimage to opengl TextureIdx

    UploadTexture( mSource_Bgr, TextureIdx[0] );
    glutMainLoop ();                            

    FreeTexture( TextureIdx[0] );           //Free our TextureIdx
    return 0;
}