简单的Java碰撞检测

Question

I'm designing a simple game where you're to avoid being hit by the AI i've created.

I've been looking up Collision detection and I have a question.

All the info i've looked up seem to involve using quite a bit of code.

I was wondering why can't a simple:

if(AI.xDirection == x || AI.yDirection == x || AI.xDirection == y || AI.yDirection == y){
        System.out.println("Collision");

Be used for this?

As you see I have it set to print to console and it seems to be working for me.

Is there a disadvantage to this?

Answer 1

不确定你的代码实际上在做什么，但如果它有效并且你可以理解，那么我不明白你为什么要改变它！

Answer 2

Your code assumes that all the client cares about is whether or not there is a collision. There may be games and other instances where the client wishes to deal with a collision in certain ways in certain situations (for example, I made a program a while ago that bounced a ball back and forth between random obstacles, and depending on which side was hit first, it had to bounce back in that direction).

The list goes on as to what the client wishes to happen after the collision, but if what you want is simply to show a collision, then hey, go for it man.

Answer 3

You violate encapsulation with this way of doing.

Prefer defines a custom object named for instance: AIPosition (likely to be immutable) dedicated to encapsulate AI coordinates.

and AIPosition containing the method: boolean doesCollideWith(AIPosition anotherPosition)

AI would contain a delegating method:

public boolean doesCollideWith(AI anotherAi){
    aiPosition.doesCollideWith(anotherAi.getAIPosition());
} 

Your call would be: if(ai1.doesCollideWith(ai2))

Thus, if later coordinates involve a third element (like z ), your client codes don't need to change.