# Angular animation with atan2

```
var diffx = (this.destination.x - pos.x), px = diffx / dist;
var diffy = (this.destination.y - pos.y), py = diffy / dist;
var angle = Math.atan2(diffy, diffx) - rot.z;
rot.set(0, 0, rot.z + angle / 24);
```

The object points to my mouse cursor. I use the above code to calculate the angle in radians and animate the angle by a few frames. However, when the variable `angle`

turns from positive to negative (in PI radians), it rotates clockwise to the new cursor position (as seen in red). However, my desired path is to go straight to the new corner (green arrow).

EDIT:

This is what I ran into, it seems to work. Can I improve?

```
if(atan - this.lastAtan < -Math.PI)
atan += Math.PI * 2;
else if(atan - this.lastAtan > Math.PI)
atan -= Math.PI * 2;
this.lastAtan = atan;
var zrot = rot.z + (atan * 12 * Game.dt);
rot.set(0, 0, zrot % (Math.PI * 2));
```

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