well, it doesn't sound very complicated to me since the mesh will be
cuted in one plan.
its like the mountain/sea case...
just make two new meshes
parse the to be cutted mesh, all faces nearer goes to mesh1, all the
ones to mesh2
all the faces where vertexes are on bothsides, you define 2 new faces
per face on border.
then a simple line cross gives you the points needed per tris, then
one of the two goes to mesh1 the other to mesh2.
the line to check being v0/v1 v1/v2, v2/v0 (assuming you check if not
both vertexes are on same side),
depending on your plane orientation and according to your drawing, the
line to check with the 2 others would be min x and max x of your plane
this can be done in a simple loop.
I also recall seing 2 or 3 papervision studies on this.
and i beleive there is even one class doing exactly this in PV... but
I'm not sure.
Fabrice
On Jun 26, 2009, at 6:21 PM, joar wrote:
Thanks Li,
I also thought about the method you suggested, but before going that
path I wanted to know if there are any other option.
Fabrice, I have an object mesh and I want to cut it with an arbitrary
plane (typically an xy-plane at different z-position determined by an
slider). I want to build (and display) the 2D polygon of that cut.
See the following skematic:
http://www.softeng.cse.clrc.ac.uk/everest/docs/post-processor/post_html/img10.gif
joar
On Jun 26, 12:11 am, Fabrice3D <[email protected]> wrote:
what is it you want to do exactly?
is it the mountain that must be separated from sea level?
the mesh cut in half?
?
Fabrice
On Jun 25, 2009, at 11:55 PM, Li wrote:
Sounds like a difficult task to me...
All I can think of is using a camera, placing it at a strategic
point and setting up materials on the geometries so that if you
render it and process it you could get an image of what your
polygons might look like. All this with a precise renderer.
Thats just a cheat though, if you want precision, I'm afraid this
would involve some complex mathematics. Plus, I'm not sure if any
part of the engine handles anything like this.
Hope it helps!
On Thu, Jun 25, 2009 at 6:18 PM, joar <[email protected]>
wrote:
Is there any way to compute the intersection between a Mesh object
and
a 3D plane?
I have some meshes that I want to intersect with 3D planes at
arbitrary positions and draw the resulting 2D polygon on that plane.
thanks,
joar
