C++ :: Video Game - Accessing Objects In Another Class?
Dec 3, 2014
I am working on a video game that is based on a tutorial I found online and I ran into an issue associated with accessing an object's method inside another class object's function without making the object global which seems bad.
Here is basically how the tutorial set things up in the game: The game has a base class called GameObject then there are other child classes that inherit from this class. The GameObject class has all the basic information an object would have that needs rendered on the screen (x/y position, size of bitmap, bitmap, whether or not it is collidable, etc).
One of the child classes SpaceShip, which is the player so it has attributes and methods associated with managing # of lives and points scored.
There are other child classes of GameObjects in the game that need to take life and add points from the SpaceShip object if they collide with the spaceship or other objects.
In the collision handling routine I basically call a function "void Collided(int objectID)" when a game object collides with another. Within the Collided() routine, there is logic that executes code or other functions based on the objectID it collided with. Some of the collisions require taking life from the spaceship or adding points. The way this was accomplished in the tutorial was with function pointers (see Bullet class constructor and collided method for example). Is this really the best way to handle this sort of thing? It seems like there has to be a simpler way than to keep referencing function pointers in any new class I want to add to the game. I realized this when I went to add a method for the spaceship to fire bullets rather than inside my game class.
I'm working on my first video game. So far I have a few classes in the game starting with the Game class which includes a list of GameObjects (another class). There are several classes that inherit from GameObjects used to implement things like bullets, explosions, various enemy types, etc.
The game essentially iterates through the list of GameObjects to update/render them. I would like to provide access to the Game's list of GameObjects inside another class (like the Bullet class) so I can put new objects on the list. For example, when a bullet hits, I want to add an explosion to the Game's GameObject list it can be updated/rendered.
How this should be setup? I was considering adding a pointer to the Game or GameObject list to the GameObject class (and methods to access it), but I was wondering if there is a better way to set this up?
We are coding a Blackjack/21 game. I have a Deck.cpp class, Deck.h, Play.cpp (holds Main), and Card.h (holds card struct). I also have a Hand class/header, but I'm not using it yet. This is what is required per instructor.I am having issues accessing the functions that are in my Deck class. I have tried a few other means to access the class's function, but I've already gotten rid of those. These three are my latest attempts with the specific errors in the comment on the line the error was happening. ve.
Here is my Deck.h
#pragma once #include <iostream> #include <fstream> #include <string> #include <cstdlib> #include <ctime> #include <iomanip> #include "Card.h" #include "Hand.h" using namespace std; class Deck
How would you create a video game in c++? I'm not sure really how to display the graphics and set properties and do all that stuff. I don't have money to buy a book about so how do you?
I was tasked with creating a program that asks for the scores of three gamers then takes these scores and outputs the highest. I THINK I have the other parts down but I don't know how to get the program to compare the scores and output the highest without having to write a long list of commands comparing playerone to playertwo, then player one to playerthree, then player two to playerone, etc.
#include <iostream> using namespace std; int main () { int playerOne, playerTwo, playerThree; cout << "Please enter score for Player One: "; cin >> playerOne;
I'm currently trying to access a variable contained within a base object from another completely different object and I continually get error messages. I'll attempt to put up the important code since it's contained within fairly large classes. From the Base .cpp file. ObjectPosition:
This is the initialization function for the BaseObject. All objects are inheriting these variables which are Protected within the ObjectPosition class.Then they are initialized within the Pig class thus wise:
I'm working on designing a game in C++ that is similar to the "find the ball under the cup" game. I have a Sonic the Hedgehog icon (weird I know, but it was the first thing that came to mind) that will be hidden underneath one of three rectangular blocks.
Here is how I envision this working:
On the main menu I have 3 buttons which represent 3 different difficulty levels Easy- blocks move 3 times at a slow speed Medium- blocks move 5 times at a slightly faster speed Hard- blocks move 10 times at a fast speed
When the user clicks one of these buttons they will be taken to the game screen.
Sonic will be displayed for 3 seconds and the user will then see him be covered with one of the three blocks.
The three blocks will then move in a random pattern along the middle of the screen at the speed and number of times associated with the button that was pressed.
Once the blocks stop moving, the user is to click on the one they think Sonic is underneath.
If they choose correctly, they'll be taken to a "Winning Screen" that displays a congratulatory message and 2 buttons. Play Again- returns the user to the main menu and the game starts over with a new random pattern. Quit- the window closes.
If they choose incorrectly, they'll be taken to a "Losing Screen" that displays a "Try Again" message and 2 buttons that have the same function as the buttons on the winning screen.
I have never worked with any kind of graphics before other than in HTML and Javascript. I have managed to create the main menu, but how to do the actual game portion of the project. I've been trying to take it a step at a time, (for example, I first figured out how to set the background color for the console window, after I got that right I figured out how to add buttons) but the rest of this seems to depend on each other.
Here is what I have so far:
Main menu:
#include "stdafx.h" #include <iostream> #include <Windows.h> using namespace std; class MainMenu
[Code]....
So I've got the screens pretty much designed now (with the exception of the game screen itself) but how to tie everything together.
In case my description wasn't too clear, here is a game that I found on Google that is pretty much exactly what I'm looking for. [URL]
Here is the link for my program, I want to access the average value which is located in grade.c (calculate_grade) class through driver.c (main function) but I don't know how to make "average" visible
I've been attempting to create a game with curses and I keep running into the problem of scope. I want to change or use variables of a different class in a different header file. But I don't know if I should use pointers, references or neither. Should I be programming in a manner that doesn't make it necessary to use variables outside of their class?
In this book, item 3 is about never treat arrays polymorphically. In the latter part of this item, the author talks about the result of deleting an array of derived class objects through a base class pointer is undefined. What does it mean? I have an example here,
Code: class B { public: B():_y(1){} virtual ~B() { cout<<"~B()"<<endl;
[Code] ....
This sample code does exactly what I want. So does the author mean the way I did is undefined?
#include <iostream> using namespace std; class superclass; class subclass1; class subclass2;
[Code] ....
As you can see I want to create a dynamically allocated storage of references to a parent class each of which can then point to a child class, how ever I do not know how to extract the child class out again from that array so i may access its variable b.
Let's say I have a Car object , and it contains inner Engine object.
Code: struct Car{ Engine mEngine; };
In order to initialize the engine object NOT by the default constructor (if it has any) , we use initialization semantics:
Code: Car::Car: mEngin(arg1,arg2,...) { other stuff here }
Now it gets tricky: Let's say a Car objects has 10 inner objects, each object has about 5 variables in it . Car is a base class for , e.g. , Toyota class. you don't want the Car class to have a constructor with 50 arguments. Can the inner objects of Car be initialized from the base class , e.g. Toyota?
Code: class Toyota: Car(...), mEngine(...), mGear(..) { ... };
The other options are: 1) like said , create a Car constructor which gets 50 arguments, then initialize Car as whole from Toyota - the code becomes less readable and less intuitive 2) Car constructor which get built-objects as arguments and initialize the inner objects with copy constructor . the code gets more readable but then you create many excess objects .
I have two classes, a Package class and a Person class. The Package class has two Person objects has member variables, a Sender and a Receiver. While overloading the << operator for the Package class so that it will make an output label from everything in the Package class. Here is my code...
class Package{ public: Person Sender; Person Reciever; int weight; double cost; friend ostream &operator<<(ostream &out, Package &pack);
[Code] .....
So my problem is on that last output line, I am unable to call Sender.getName()... etc. Is there a proper syntax so that I can access the members of the Person class while overloading the << operator for the Package class?
I have been working on an assignment where I have to add three objects of a class Matrix. The class should have the flexibility to add more than two oprands without changing any operand on Left hand side of the '=' operator.
