[Bf-python] Mathutils additions

[Campbell Barton]

Gosh, all the things I need are available in blenders existing C 
functions :)

- Cam


Campbell Barton wrote:

> 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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>>
>>
>
>


-- 
Campbell J Barton

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