Snake Game design

Question

I am designing Classic Snake game using OOPS.I will have the following classes at top level :

Game {
   Board board,
   Snake snake;
}
    
Board {
   Cell cells[];
}

Cell {
   int x,
   int y,
   Type type;
}

Type {
   SNAKE,
   FOOD,
   EMPTY
}

Snake {
   List<Cells> snakeParts;
}

I am a little confused on following point:

Can snake be part of Board class as follow?

Board {
   Cell cells[];
   Snake snake;
}

Like instead of Game class having Snake object, is it better for Board class to have snake object?Because it makes sense to say that BOARD 'has-a' snake instead of Game 'has-a' snake .

When I have done this game, I have gone with the Game 'has-a' Snake. I consider the board a different level of abstraction. I consider the board what we use to communicate to the engine what to draw. So I put an architectural line there. The board should not depend on something more abstract than itself (such as the snake). By the way, there is another way: The Snake 'has-a' Board. And it is responsible of updating it. — Theraot, Feb 22 '21 at 08:43
yeah probably for me also Game "has-a" snake makes more sense — stkUser, Feb 22 '21 at 17:38

score 4 · Accepted Answer · answered Feb 22 '21 at 08:18

If you are trying to do Object-Orientation I would suggest a different approach.

Contrary to what structured design and entity relationship diagrams suggest, there is no inherent relationship between things in a oo system. All relationships are derived from requirements and ultimately the behavior objects must support. Without behavior it makes no sense to talk about relationships.

For example, are "food" and "snake" the same type, or implement the same interface? Depends what their behavior is. Both can be thought of as being able to be presented on the board. This is sort of similar, so they could be related types. But, I could also model that as the "snake" being something I can give directions to, and the "food" not. So in that case they would probably not be related.

So your question of "Can snake be part of Board class as follow?" is an implementation detail, not an objective fact that you can discuss just in itself. Whether it will be depends on how you choose to implement them (what "behavior" you assign to objects). Different trade-offs will lead to different designs and different relationships.

Relationships between objects is a consequence of your design, not the other way.

Alexander Petrov · Answer 2 · 2021-02-21T12:56:01.410

3

If you just look at the board. I think it does not realy care if there is a snake positioned on it or an apple positioned on it. A board is a set of Cells as you pointed out and a certain sequence of Cells may form a Snake or an Apple.

I would lay the following abstraction.

Pattern has Cells
Snake is a Pattern
Apple is a Pattern of 1

Snake is Alive until Pattern has no double crossing (repeating cell)

Game has a Snake that is Alive. Dead Snake - Game Over.

Board is not that significant by the way as it is just an arrangment of Cells - if it is a square or Kvadrat board you can effectivly ignore it. The board abstraction may become nessessary if your board geography is non trivial.

From the perspective of the Board the only thing that matters(potentialy) is what is the geography of the Cells and if a Cell is lit or not lit.

edited Feb 21 '21 at 12:56

answered Feb 21 '21 at 12:36

Alexander Petrov

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5
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But since game is specific to snake and not apples and others, dont you think we should have snake as a pattern of cells?Board is required for my case.In case i have board class, do you see snake as a part of board or independent defined in game class? – stkUser Feb 21 '21 at 13:04
1

First you never know what can be positioned on the board. The apple lets say is a food. Tmorrow you can have a Super Food or just an obstacle. One way to use the board is to use it to determin the bening and the end of the snake. When you move you are effectivly picking a new cell from the board. This cell needs to be connected to the head of the snake obviously and should not be already occupied. Also you need to release the tail of the snake. Personaly I don't see the Board as annything beyond a View of the Cells - litt unlitt. – Alexander Petrov Feb 21 '21 at 13:19

Snake Game design

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