That's the Number3D syndrome :))
Last week lost hours on a vector.subtract(othervector);

Fabrice

On Dec 4, 2010, at 7:12 PM, Michael Iv wrote:

> Ha Ha ,shame on me,thanks  a lot John ! What dumb mistake..Kind of irritating 
> stuff you could spend hours on I should defenitely take a break from coding 
> ... :)
> 
> On Sat, Dec 4, 2010 at 8:07 PM, John Brookea out s <[email protected]> 
> wrote:
> Crossproduct returns a vector3D
> 
> trace(mouseVector.crossProduct(vector))
> trace(mouseVector)
> 
> 
> 
> On 4 December 2010 16:34, Michael Iv <[email protected]> wrote:
> Hi  all.  I have been working on converting some stuff to Away3.6/
> I was surprised to find that Flash player vector.crossProduct() returns quite 
> different result than number3D.cross().
> First of all I am sure that number3d.cross() is right because calculating 
> cross product manually I arrived to the same result.Here is example.
> 
> Cross by number3d.cross:
>                 var vector:Vector3D=new Vector3D();
>              
>                 var mouseVector:Vector3D=new Vector3D(400 - mouseX, mouseY - 
> 300, 0);
>              
>                vector.cross(new Vector3D(0,0,1),mouseVector)
> 
> let's say mouseVector is 87,2,0 then the result is ----->2,-87,0
> also doing it manually based on 3d math operation:
> 
> private function crossP(v1:Vector3D,v2:Vector3D):Vector3D{
>             var crossVec:Vector3D=new Vector3D();
>             crossVec.x=v1.y*v2.z-v1.z*v2.y;
>             crossVec.y=v1.z*v2.x-v1.x*v2.z;
>             crossVec.z=v1.x*v2.y-v1.y*v2.x;
>             return crossVec;
>             
>         }
> rerturns the same result .
> 
> Now check this out:
>                 var vector:Vector3D=new Vector3D(0,0,1);
>               
>                 var mouseVector:Vector3D=new Vector3D(400 - mouseX, mouseY - 
> 300, 0);
>                 
>                 mouseVector.crossProduct(vector);
>  
>                 mouseVector  is-->87,2,0
> 
> WTF????
> 
> 
> 
> -- 
> Michael Ivanov ,Programmer
> Neurotech Solutions Ltd.
> Flex|Air |3D|Unity|
> www.neurotechresearch.com
> http://blog.alladvanced.net
> http://www.meetup.com/GO3D-Games-Opensource-3D/
> Tel:054-4962254
> [email protected]
> [email protected]
> 
> 
> 
> 
> 
> -- 
> Michael Ivanov ,Programmer
> Neurotech Solutions Ltd.
> Flex|Air |3D|Unity|
> www.neurotechresearch.com
> http://blog.alladvanced.net
> http://www.meetup.com/GO3D-Games-Opensource-3D/
> Tel:054-4962254
> [email protected]
> [email protected]
> 

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