I write a game on JS (platformer). The player is represented in the form of a square, the tiles of the cards are also squares. At each frame I define whether there is a player’s collision fact with any of the nearest tiles:

```
if (a.position.x & lt; = b.position.x + b.width & amp; & amp;
a.position.x + a.width & gt; = b.position.x & amp; & amp;
a.position.y & lt; = b.position.y + B.Height & amp; & amp;
A.Height + a.position.y & gt; = b.position.y) {
Console.log ('Collision!');
}
```

So I define whether there is a collision in general, but how to determine if the collision happened, which is the side of the player encountered a tile? Considering that this is a trivial task in developing games, probably there is some kind of classic algorithm for solving it. What is he?

## Answer 1, Authority 100%

Calculate the coordinates of the center of each square, then the difference

```
var acter = {x: a.position.x + a.width / 2, y: a.position. y + a.Height / 2};
var BCenter = {x: b.position.x + b.width / 2, y: b.position.y + B.Height / 2};
var d = {x: acenter.x - bcenter.x, y: acenter.y - BCenter.y};
```

Then in D you will have a direction from one square to another. For example, if D.x is greater than zero, then one square is right than the other. Or on tangent an angle can be calculated.