[vtkusers] Re: 3D object projected on a plane

[Goodwin Lawlor]

Monica Gemo wrote:
> Hello vtkers,
> I am not experienced with vtk and I need your help to calculate
> the 2D projection of a 3D object on a given plane .
> I tried to use vtkCutter and have an intersection of the 3D object on 
> the plane,
> this gives an approximation, but not the exact projection.
> 
> Is there an effective way to deal with this case in vtk?
> 
> Any suggestion is more than welcome!
> 
> Thanks a lot,
> Monica
> 
>  Monica Gemo - Ph.D. Student
Hi Monica,

Have a look at the ProjectPoint method in vtkPlane if you want to 
project the geometry.

If you want to get a  2d outline of your 3d object you can try this:

Set the renderer's view plane as the plane you want to project on to 
(set the active camera's position and focal point) then use this 
pipeline: vtkRenderWindow->vtkWindowToImageFilter->vtkContourFilter. You 
have to set the renderer's background colour to white, set the actor's 
colour to black, and use 127.5 as the contour value.


hth

Goodwin