(Qt) How to use a value from another function? - c++

Question

So here's my issue. I'm making an extremely simple game in Qt, but I'm having trouble increasing the difficulty in the game. For example, once your score hits a certain value, you level up. In game the text changes and says Level 2, but the game doesn't get any harder. I have the idea to achieve this by making the enemies move faster. I have the enemies moving at a predefined value, but I want the position change to be equal to the value "speed" in Level.cpp. The answer is probably staring me in the face, but it's the simplest answers that always get me. Below is a header and 2 source files that connect Level.cpp and Enemy.cpp.
Enemy.cpp
#include "Enemy.h"
#include <QTimer>
#include <QGraphicsScene>
#include <QList>
#include <stdlib.h>
#include "Game.h"
#include "Level.h"
extern Game * game;
Enemy::Enemy(QGraphicsItem *parent): QObject(), QGraphicsPixmapItem(parent){
//set random x position
int random_number = rand() % 700;
setPos(random_number,0);
// drew the rect
setPixmap(QPixmap(":/images/enemy.png"));
setTransformOriginPoint(50,50);
// make/connect a timer to move() the enemy every so often
QTimer * timer = new QTimer(this);
connect(timer,SIGNAL(timeout()),this,SLOT(move()));
// start the timer
timer->start(30);
}
void Enemy::move(){
// move enemy down
setPos(x(),y()+7);
//Instead of 7 above, use speed from Level.cpp
// destroy enemy when it goes out of the screen
if (pos().y() > 600){
//decrease the health
game->health->decrease();
scene()->removeItem(this);
delete this;
}
}
Level.cpp
#include "Level.h"
#include "Enemy.h"
#include <QFont>
Level::Level(QGraphicsItem *parent): QGraphicsTextItem(parent){
// initialize the score to 0
level = 1;
speed = 5;
// draw the text
setPlainText(QString("Level: ") + QString::number(level)); // Level: 0
setDefaultTextColor(Qt::green);
setFont(QFont("times",16));
}
void Level::LevelUp(){
level++;
speed = speed+2;
setPlainText(QString("Level: ") + QString::number(level)); // Level: 1
}
int Level::getLevel(){
return level;
return speed;
}
Level.h
#ifndef LEVEL_H
#define LEVEL_H
#include <QGraphicsTextItem>
class Level: public QGraphicsTextItem{
public:
Level(QGraphicsItem * parent=0);
int getLevel();
void LevelUp();
int speed; //speed is public because I got "int is private" errors on a few things I tried.
private:
int level;
};
#endif // LEVEL_H
Thanks for any help, and if possible in-depth explanations on what you did to solve the issue.
EDIT: Would my issue be trying to send out Speed, but being unable to because the Level function is labled as a QGraphicsTextItem? Will I just need to create a separate function to increase speed?

Answer 1

not sure which design pattern you are using, but sounds you need a controller to control enemy object. So basically whenever level is changed the level obj should tell the controller, well now enemy should increase speed. Then the controller will notify the enemy.