title: What about the types int2, int3, float2, float3 etc
body: <p>I've seen different code snippets using these types, but I haven't seen if they are defined in some &lt;standard header file&gt; or just defined in a "local header file" or even at file level.</p>
  
  <p>So what Im wondering is: Is there any standard header file that defines these types? Or is there some standard definitions that everyone uses that I should copy?</p>
  
  <p>I guess that a possible and common use to these types are representing coordinates, am I wrong?</p>
  
  <p>Is there anything else I should think about if I want to use these to represent positions in a grid? Any reasons why or why not to use them?</p>
  
  <p>EDIT:</p>
  
  <p>Clarification: int2 means a pair of ints, float3 means a triplet of floats.</p>
  
  <p>If these types were predefined somewhere it would be nice to use them instead of having to write it from scratch including the standard algebraic functions (operator+, operator-, etc.).</p>