<div dir="ltr"><div>Props can be anywhere. But if you want them to be visible, they must lie between the near clipping plane and the far clipping plane, which are set with camera->SetClippingRange(double dNear, double dFar). These are set as distances from your camera position. In order for things to be visible, they must be at least "dNear" distance from the camera, and must not be further than "dFar" distance from the camera.</div>
<div><br></div><div>"Position" is always the camera position in world coordinates.<br></div><div><br></div><div>"FocalPoint" must lie between the green point and the purple point that are shown on your diagram. I recommend that it be within the grey blob (i.e. within the "patient").</div>
<div><br></div><div>And of course I highly recommend that you set the ClippingRange as well. The dNear can be set to half of the distance from the camera position to the focal point, and the dFar should be set to the distance from the camera position to the detector.</div>
<div><br></div><div><div><div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Apr 17, 2013 at 3:27 PM, Taylor Braun-Jones <span dir="ltr"><<a href="mailto:taylor@braun-jones.org" target="_blank">taylor@braun-jones.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hello vtkusers,<div><br></div><div>I'm trying to position and orient a vtkCamera to model an X-Ray camera as shown in the figure below.</div>
<div><br></div><div><img src="cid:ii_13e19d34a9887059" alt="Inline image 1"><br>
</div><div><br></div><div>I'm running into uses so I just want to make sure this is fundamentally possible with a vtkCamera. I know:</div><div><br></div><div> - Position and orientation of the camera coordinate system (red axes) in world space</div>
<div> - X-Ray point source (green point)</div><div> - Principal point (purple point)</div><div> - The width, d, of the square detector (and therefore the view angle)</div><div><br></div><div>
(1) Can I place Props between the camera Position and FocalPoint?</div><div><br></div><div><div>(1a) If so, how should the Position and FocalPoint be set?</div><div><div><br></div><div>(1a) If not, is there another approach to set the Position/FocalPoint/ViewUp to simulate this?</div>
</div><div><br></div></div><div>Thanks!</div><span><font color="#888888"><div>Taylor</div></font></span></div>
<br><br>
<br></blockquote></div><br></div></div></div></div></div>