Collision detection in a Java game?

Question

I am developing a game in which I have a problem of detecting collisions of moving images. The game has a spaceship and the number of asteroids (obstacles). I want to detect a collision between them. How can i do this?

Answer 1

Collision detection is usually difficult for anything but rectangles.

The way I did this in the past is to provide both an image and a mask for each object. So, for example, an object such as the Jupiter 2 spaceship from Lost in Space will have the following image and mask:

     X            00000100000
  XXXXXXX         00111111100
 X       X        01111111110
X         X       11111111111
 X       X        01111111110
  XXXXXXX         00111111100
    XXX           00001110000

- , , - , . , 1 - .

:

• , . , .
• 1, .
• 2, .
• - 2 1.
• 1 1 , .

" ", , . - .

, - :

....xx....
..xx..xx..
.x......x.
.x......x.
x........x
x........x
.x......x.
.x......x.
..xx..xx..
....xx.**y.....
       .y......
       yyyyyyyy
       .y......
       ..y.....

, , (. **y), . , , .

---

@kyoryu . , , ( ). , ( ) X Y , Z:

    YYYY                .Z.
    YYYY                .Z.
XXXXXXXXXXXX            .Z.
XXXXXXXXXXXX            ZZZ
XXXXXXXXXXXX            .Z.
XXXXXXXXXXXX

. , , . ( , ).

Answer 2

, , , .

c^2 = a^2 + b^2

, , , , ? :

distX ^ 2 + distY ^ 2 <= (radius1 + radious2) ^ 2 == COLLISION!

distX distY - 1 + 2 , .

- , , , .

Answer 3

. x, :

• .

, , .

first.right < second.left

, .

first.left > second.right

, x.

y ( ), , y - , ! , 2- .

, , O (N ^ 2).

Answer 4

X Y , , , x y. :

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comming down



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Minus width and height to find out correct x and y