Mathf.Repeat vs Mathf.PingPong

Could someone please explain what exactly Mathf.Repeat and Mathf.PingPong do in a bit more detail than the docs? I'm just not quite getting it.

thanx!
d

 

Repeat is the same as the modulo operator. (Which btw. does work with floats.)

Repeat(t, length) works a bit like this (for positive t):

Code (csharp):

1.  
2.    if t is less than length, return t unmodified.
3.    if t is greater than length, subtract length from t until t is less than length
4.  

Example:

Code (csharp):

1.  
2.    // Will print 0,1,2,0,1,2,0,1,2
3.    foreach( var t in [0,1,2,3,4,5,6,7,8]) {
4.        print(Mathf.Repeat(t, 3));
5.    }
6.  

PingPong will reverse the interval on every second repeat.

Code (csharp):

1.  
2.    // Will print 0,1,2,3,2,1,0,1,2
3.    foreach( var t in [0,1,2,3,4,5,6,7,8]) {
4.        print(Mathf.PingPong(t, 3));
5.    }
6.  

PingPong could actually be implemented using Repeat like this:

Code (csharp):

1.  
2.     function MyPingPong(t, length) {
3.         var result=Mathf.Repeat(t, length*2);
4.         if( result > length)
5.              result = (2*length) - result;
6.         return result;
7.     }
8.  

 

Thanx for that exlpanation. Now I understand the .mov texture animation script i've been using.

Still not so sure I understand Mathf.PingPong or what you'd use that for, though.

thanx again!
d

 

If you used Repeat in the mov script to loop an animation, using PingPong would let it play backwards and forwards instead.

 

Oh, i get it! Really had to hit me over the head with that one! That's really cool to have a built-in function that does that.