[quote name='pinebanana' timestamp='1358924066' post='5024617']
Shouldn't it be:
[/quote]
It's rather trivial in this case; nothing will be harmed by assigning three floats to themselves. Past attempting to maintain the invariants of the class, there is little other reason to check to see if you are assigning to yourself for a class that contains nothing but primitive types.

http://www.parashift.com/c++-faq/self-assignment-how.html

If you don't need to explicitly test for self-assignment, for example, if your code works correctly (even if slowly) in the case of self-assignment, then do not put an if test in your assignment operator just to make the self-assignment case fast. The reason is simple: self-assignment is almost always rare, so it merely needs to be correct - it does not need to be efficient. Adding the unnecessary if statement would make a rare case faster by adding an extra conditional-branch to the normal case, punishing the many to benefit the few.

In other words, don't stick one in just to do it. Do it for a provable reason that isn't speed.

[quote name='pinebanana' timestamp='1358929687' post='5024636']
Ah, my bad.
[/quote]
No harm done.

Btw, since equality operator in a Vector3 class is highly likely to be used frequently, you should seriously consider inlining it back. Just make sure it's available all translation units. You can define it in the header, or to make the code more tidy and clean, define it in an "inl" file and include it in the Vector3 header.

okeys, just to let you guys know, i read everything and learned more then i asked for.

thanks for all the insight, it really helps once you go back to optimizing just having heard about this stuff and spending a thought on this or two.

but for now, i am just happy it works now as expected, and i know what went wrong. never hurts to keep conventions though =)

MyClass & operator=(const MyClass &) = default;