[vtkusers] Misleading documentation in vtkCamera::GetFrustumPlanes

joopeter joo.peter at gmail.com
Mon Jun 23 10:52:10 EDT 2014


http://www.vtk.org/doc/nightly/html/classvtkCamera.html#a63ac225662fc7b81628366a7b3b7096c

Hello, I found that the documentation is misleading, because it tells that
the order of the planes is:
left,right,bottom,top,far,near

Debugging VTK revealed that the actual order is
left,right,bottom,top,near,far

This is how I verified that it is wrong: I created 10 equidistant points
from the camera position (outside the frustum) to the focal point (inside
the frustum) and I checked the signed distances of the last and the second
last planes.

The second last remained positive (far plane, oriented inward) while the
last went from negative to positive. That is the behavior of the near plane!
the first point is the camera, which is outside of the viewing frustum,
therefore it has negative sign, the last is the focal point for which the
signed distance was positive.

Please fix+comment :)






--
View this message in context: http://vtk.1045678.n5.nabble.com/Misleading-documentation-in-vtkCamera-GetFrustumPlanes-tp5727606.html
Sent from the VTK - Users mailing list archive at Nabble.com.


More information about the vtkusers mailing list