[Bf-python] Mathutils additions

[Campbell Barton]

Hi, The method is as follows in C

        length = sqrt(pow((v2[0] - v1[0]),2) + pow((v2[1] - v1[1]),2) + 
pow((v2[2] - v1[2]),2) );

This measures the real length (not the quick and disty method)

- Area of a triangle

      p = el1 + el2 + el3; /* Get the perimeter from the edge lengths */
      area = 0.25 * sqrt(p * ((p-el1)*(p-el2)*(p-el3)));


- Cam


Jonathan Merritt wrote:


> Hi Campbell,
>
> Campbell Barton wrote:
>
>> Mathutils.getVecDist(vecA, vecB) # measures the distance in 3d space 
>> between 2 vectors
>
>
>
> Just a question about this one: do you mean the Euclidean distance 
> between two points?  ie:
>    || A - B ||
> Where A and B are the Cartesian locations of a pair of points?
>
>> The names could realy be anything but Im interested to know if I 
>> coded this weather people would use it.
>
>
>
> Definitely! :-)  I'd just be picky about the name getVecDist() - I'd 
> rather see it named getPointDist() or something.
> A "distance between two vectors" is a less well-defined concept, since 
> it really only applies in the form above if the two vectors exist in 
> the same coordinate system.  Sure, points must *also* be in the same 
> coordinate system, but IMHO, that's more obvious.  There are many, 
> many cases in 3D graphics where vectors are specified in the same 
> rotational coordinate frame (so you can take dot and cross products, 
> etc.), but they have an implicit translation offset (eg: the camera 
> view vector and a normal to a face, to pick an example off the top of 
> my head).
>
> Jonathan Merritt.
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>


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Campbell J Barton

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