OpenGL - Mouse Function

/**

 * This function is called by glutMouseFunc(mouse)

 * The parameter here is

 * button : type of the button

 * state: down and up

 * x: horizontal position, start from left

 * y: vertical position, start from top

 */

void mouse(int button, int state, int x, int y){

    // called twice
    cout << "State: " << state << endl;
    cout << "Position: x->" << x << " y->" << y << endl;
    switch(button){
        case GLUT_LEFT_BUTTON:
            cout << "Left Button" << endl;   // called twice
            if(state == GLUT_DOWN){
                cout << "Left Button Down" << endl;
            }
            if(state == GLUT_UP){
                cout << "Left Button Up" << endl;
            }
            break;
        case GLUT_MIDDLE_BUTTON:
            cout << "Middle Button" << endl;
            if(state == GLUT_DOWN){
                cout << "Middle Button Down" << endl;
            }
            if(state == GLUT_UP){
                cout << "Middle Button Up" << endl;
            }
            break;
        case GLUT_RIGHT_BUTTON:
            cout << "Right Button" << endl;
            if(state == GLUT_DOWN){
                cout << "Right Button Down" << endl;
            }else if(state == GLUT_UP){
                cout << "Right Button Up " << endl;
            }
    }
}

OpenGL - Mouse Function