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Bindings - other languages => DotNet => Topic started by: Mario1159 on July 14, 2018, 10:50:11 pm

Title: Inheritance question [SOLVED]
Post by: Mario1159 on July 14, 2018, 10:50:11 pm

(https://i.imgur.com/3gh7y6P.jpg)
I want to access to the rectangle/convex/circle methods in my sGameObject, dGameObjects or Player class but i dont know how, because my current class sGameObject just have a Shape {get;set;} so i can create for example a sGameObject doing this:

RectangleShape rectangleShape = new RectangleShape(new Vector2f(50f,50f));
SGameObject box = new SGameObject();
box.Shape = rectangleShape;

//but i cant access to the RectangleShape methods
box.RectangleShape.getSize(); // error
 

Title: Re: Inheritance question
Post by: dabbertorres on July 15, 2018, 12:12:21 am

You've kind of half-answered your own question I think...

As you said, your SGameObject class has a Shape field. So you should be accessing the field's GetSize() method.

As in, box.Shape.GetSize(). Right?

Title: Re: Inheritance question
Post by: Mario1159 on July 15, 2018, 01:22:16 am

Shape doesnt have a definition for GetSize (https://www.sfmldev.org/documentation/2.5.0/classsf_1_1Shape.php)
however the RectangleShape has the getSize method but i cant access to that in my sGameObject class
or maybe i didnt understood your answer correctly.

Title: Re: Inheritance question
Post by: Hapax on July 15, 2018, 04:08:55 am

I don't think your inheritance flow makes sense.

Is it possible that a "dynamic game object" that "can move" is a "static game object" that "can't move"?

I honestly think it needs some more careful thought.



Anyway, from the shapes to Shape and back, you can cast. Just be really careful to make sure that they are the thing you are casting them to/from.
For example:

sf::RectangleShape* rectangle = new sf::Rectangle;
sf::Shape* shape = dynamic_cast<sf::Shape*>(rectangle);
// ...
sf::RectangleShape* thatRectangle = dynamic_cast<sf::RectangleShape*>(shape);

That's untested. It's also a pretty volatile system :P

Title: Re: Inheritance question
Post by: Mario1159 on July 15, 2018, 04:54:34 am

It works! thanks and also thanks for the quote about my inheritance flow because im a beginner in concepts of oop and my code always tend to look like a spaghetti

Title: Re: Inheritance question [SOLVED]
Post by: eXpl0it3r on July 16, 2018, 10:13:19 am

It's also recommended to use composition over inheritance. While might argue that your game object is a shape of some sort, it's better to just have it as a member of the game object (has a relationship).

This makes for a better design as you don't force the interface of shape classes onto your game object classes and you can better encapsulate the object logic.

Are you working with C# then?

Title: Re: Inheritance question [SOLVED]
Post by: Mario1159 on July 16, 2018, 06:52:24 pm

Yes, im working in c# and thanks for the recommendation