glShadeModel(GL_SMOOTH);
        glMatrixMode(GL_PROJECTION);
    glPushMatrix();
    glLoadIdentity();

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glLoadIdentity();

  //      glOrtho(0.0f,640,480, 0.0f,-1.0f,1.0f);
        //glOrtho(0.0, 640, 0.0, 480, -1.0, 1.0);

    // render
    glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
    glClear(GL_COLOR_BUFFER_BIT ); //| GL_DEPTH_BUFFER_BIT);
    //glDisable(GL_DEPTH_TEST);
    glBindTexture(GL_TEXTURE_2D, color_tex);
    glEnable(GL_TEXTURE_2D);
    glColor4f(1.0f,1.0f,1.0f,1.0f);



    // inverted y-TexCoord!
    glBegin(GL_QUADS);
                glTexCoord2f (0.0, 0.0);
            glVertex3f (-1, -1, -0.5);
            glTexCoord2f (1.0, 0.0);
            glVertex3f (1, -1, -0.5);
            glTexCoord2f (1.0, 1.0);
            glVertex3f (1, 1, -0.5);
            glTexCoord2f (0.0, 1.0);
            glVertex3f (-1, 1, -0.5);
    glEnd();

    // end


        glMatrixMode(GL_PROJECTION);
    glPopMatrix();

        glMatrixMode(GL_MODELVIEW);
    glPopMatrix();

        glFlush();