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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Indeed, it is simple David, as I discovered after posting that query :)<br>
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Thanks<br>
Gib<br>
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<div style="direction: ltr;" id="divRpF341137"><font size="2" color="#000000" face="Tahoma"><b>From:</b> David Gobbi [david.gobbi@gmail.com]<br>
<b>Sent:</b> Thursday, 6 November 2014 5:34 p.m.<br>
<b>To:</b> Gib Bogle<br>
<b>Cc:</b> vtkusers@vtk.org<br>
<b>Subject:</b> Re: [vtkusers] Transform axes<br>
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<div dir="ltr">Hi Gib,
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<div>If I'm reading your question correctly, then what you are looking</div>
<div>for is very easy to achieve.</div>
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<div>To transform an object from its canonical x,y,z axes onto a</div>
<div>new set of orthogonal axes, all you need is to set the first three</div>
<div>columns of a 4x4 matrix to those axes.</div>
<div><br>
</div>
<div>if the axis vectors are u, v, and w, then the transform matrix is</div>
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<div>u_x, v_x, w_x, 0,</div>
<div>u_y, v_y, w_y, 0,</div>
<div>u_z, v_z, w_z, 0,</div>
<div>0, 0, 0, 1</div>
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<div>No algebra involved!</div>
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<div> - David</div>
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<div class="gmail_quote">On Wed, Nov 5, 2014 at 5:47 PM, Gib Bogle <span dir="ltr">
<<a href="mailto:g.bogle@auckland.ac.nz" target="_blank">g.bogle@auckland.ac.nz</a>></span> wrote:<br>
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<div style="direction:ltr; font-family:Tahoma; color:#000000; font-size:10pt">Hi all,<br>
<br>
This is a 3D geometry problem, one that many people must have solved. I want to apply a transform to my actor to bring it's local axes (which are initially aligned with the global axes) into alignment with a specified triplet of orthogonal vectors. In fact
alignment with a pair is sufficient. I'm hoping that somebody has done this in VTK and can save me the trouble of going through the algebra.<br>
<br>
Thanks<span class="HOEnZb"><font color="#888888"><br>
Gib<br>
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