VDist(P1,P2) is just short (as if ;)) for vlength(P2-P1), i prefer the latter
because it saves me an #include but it doesn't really make a difference.

I *am* taking the y-component into account:
Basically I work with the rectangular triangle with vertices P1, P1+<d.x, 0,
d.z> and P1+<d.x, d.y, d.z> = P1+d = P2. (draw a picture if you need to). The
ratio of the length of the horizontal component (vlength(<d.x, 0, d.z>) = b) and
the length of the vertical component (d.y) determine the shear matrix.

The actual distance length(d) appears in the second version as a normalization
constant. In the first version it does not appear explicitly, but mathematically
it is still in there somewhere as it is well defined by the lengths b and d.y
via phytagoras.

Regards Roman


Thomas de Groot <tenDOTlnDOTretniATtoorgedDOTt> wrote:
> Thank you Roman, for your help! This works fine.
>
> One question: you use vlength() instead of VDist() and seem not to take
> into account the y-component. However, it seems to me that between P1
> and P2 the y-component can potentially be of importance especially if
> height differences are large. Would that not be compensated by VDist()?
> Or vlength(d)?
>
> Thomas

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Again, Thank you indeed Roman. I shall study this more in depth later on 
in order to understand it better.

See in p.b.i. for the application of your code :-)

Thomas

On 14-7-2011 16:48, Roman Reiner wrote:
> VDist(P1,P2) is just short (as if ;)) for vlength(P2-P1), i prefer the latter
> because it saves me an #include but it doesn't really make a difference.
>
> I *am* taking the y-component into account:
> Basically I work with the rectangular triangle with vertices P1, P1+<d.x, 0,
> d.z>  and P1+<d.x, d.y, d.z>  = P1+d = P2. (draw a picture if you need to). The
> ratio of the length of the horizontal component (vlength(<d.x, 0, d.z>) = b) and
> the length of the vertical component (d.y) determine the shear matrix.
>
> The actual distance length(d) appears in the second version as a normalization
> constant. In the first version it does not appear explicitly, but mathematically
> it is still in there somewhere as it is well defined by the lengths b and d.y
> via phytagoras.
>
> Regards Roman
>
>
> Thomas de Groot<tenDOTlnDOTretniATtoorgedDOTt>  wrote:
>> Thank you Roman, for your help! This works fine.
>>
>> One question: you use vlength() instead of VDist() and seem not to take
>> into account the y-component. However, it seems to me that between P1
>> and P2 the y-component can potentially be of importance especially if
>> height differences are large. Would that not be compensated by VDist()?
>> Or vlength(d)?
>>
>> Thomas
>
>
>

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