intersection between solid and surface

Hi, is it possible to to create an intersection between a 3d surface (non planar) with a solid (a pyramid) that cross that surface?

I'm using Autocad 2004 and I'm not able to create the intersection line.

Tnx

i don't quite get what you are trying to achieve can you explian alittle more as to what you hoping to end with or achieve ?

I have a ship hull, only 3d surface created by 4 lines in space and I have to create the trace of a solid pyramid that go through the hull.

I hope it is clear enough

Your description of your problem is still a little vague. I don't believe intersect works with nonplanar surfaces, so what you may be trying to do is impossible. Can you attach a dwg or at least a picture?

I use AutoCAD 2k6 but I read that in 2k7 you can "cut out" a solid based on the surface (hull).

Or use the m2s lisp to transform the surface in solid.

Once you get the surface as solid you may use the regular Intersect command, explode the resulted solid to get the intersection curve and move it back on a copy of the surface.

Just my opinion...

I try to use m2s and it works, thanks

Making it clear...

..if you succeed it wasn't SURFACE but a (polygon) MESH. Difference is essential!

One can find solution in creating solid from surface here:

c a d f o r u m . c z / c a d f o r u m _ e n / q a I D . a s p ? t i p = 5 1 1 7

(I can't send the links yet so delete all SPACES to link with the website)

In some easy cases (simple surfaces) this tips can be useful... But in general –

From my experience, to accomplish the task with ANY SURFACE (even self-intersecting one) which INTERSECT THE SOLID reliable is command SLICE (acad2008).

>After choosing solid to cut one must specify slicing plane (press S for Surface) and later need to decide if you want to keep solids on both sides of surface or not...

Apparently this is also the way to create solid from surface (because eventually you get 3dsolid which one edge is imprint of surface)...

However using it in this purpose there is also one condition: existing intersection of solid & surface must fully be consisted in surface extent...

Sometimes problems may appear (especially if I’m creating surface from profiles using LOFT command which represents eg. 3d terrain model as interpolation between profiles) because the edges of the surface are splines... That makes it complicated but not impossible... just need to create a outline of surface and offset it inside (to be consisted into surface extent) and then EXTRUDE this outline to be solid.. and then cut (SLICE)...

…And that’s how I’m approaching to the last thing I wanted to mention…

Having THIS SLICED 3DSOLID (where one of edges is the imprint of existing surface) one can do union/substract/interference every solid (basic Boolean operations referring to 3dsolids…). However sometimes errors happen working on these kind of solids but it doesn’t happen very often (nothing happens after the Boolean command).

I assume it’s a bug but if you have similar problems and you manage to find the solution it would be useful…

I hope it’s useful post.

since your object is a pyramid(or is it a cone), your intersection should be multiple lines(or one curve). can you give me an idea of the scale here, is the pyramid large compared to the ship hull or much smaller than the hull?