Re: [ quesa-Bugs-909213 ] SetRotateVectorToVector problem

[Roger H. <rog...@mi...>]

Maybe we should get Q3Vector3D_Normalize to check for
1 and -1 in its result, and if found, set the other components
to zero.

Roger.


> Initial Comment:
> Some input values for
> Q3Quaternion_SetRotateVectorToVector produce duff
> quaternions.
>
> Example:
>
> start vector:
> -0.2252647,-0.8941119,-182972.5
>
> put through Q3Vector3D_Normalize gives
> -1.231140e-6,-4.886592e-6,-1
>
> Now do Q3Quaternion_SetRotateVectorToVector with
> the following parameters:
> v1=-1.231140e-6,-4.886592e-6,-1
> v2=0,0,1
>
> the resulting quaternion is (0,-INF,INF,NAN)
>
> This problem occurs on Mac OS X Quesa, I am unable to
> reproduce it on Windows.
>
> To workaround this case, I just detect magnitudes <1e-
> 5 and set them to 0, and hence v1 becomes 0,0,-1,
> which then works correctly.
>