Entity translation NaN bug.

I have had this bug for a while now. For some reason, occasionally one of my entities translation will become NaN. I have checks in my code to detect this and they aren't triggered. But when I try to access the translation, it is NaN. Any ideas?

Unity 2019.3.2f1

 

math.normalize is often a good culprit

 

How do you check this? Keep in mind that, by definition, any comparison of

NaN

with any other value (or

NaN

) will result in

false

. If you want to check if a value is

NaN

, you have to use either

math.isnan

or

float.IsNaN

.

 

You are right. I wonder why they have normalize and normalize safe? Why would someone want to get NaN?

 

I was using math.isnan but I did not even think to check math.normalize. I did not know it could return NaN. Issue solved!

 

If you know that you don't have a zero-sized vector already (because you checked elsewhere or its impossible to get into that situation in your code) then you can avoid the extra operations required to handle that case. There is a good argument for having both options, but what the default should be is debatable.

Right now we have normalize() and normalizesafe(), people will likely gravitate toward using normalize and not the safe version (even though both should show up in the type-ahead/intelliesense.

If instead we had normalize() and normalizeunsafe() then people would get the safer alternative by default, but possibly at the expense of wasted performance.

 

i suspect it's done how it is because it's a mathematics library and normalize is the mathematically correct version

dividing by 0 is NaN