A few questions about a 3D city planning model I'm working on

[henriquebsoares]

Hello!

I am currently creating a 3D model in AutoCAD 2007 for analysis rather than rendering/visualization purposes but I'm having a few difficulties, if anyone can offer any tips, I'd really appreciate it.

I first created a terrain in Autodesk VIZ from a large set of DWG polylines representing contours and then exported it back into AutoCAD, where I had created several regions to represent roads/streets as well as green areas (as well as modeled a few solids to represent building volumes).

After that, I extruded those road and green area shapes to create 3D solids that would intersect with a copy of the terrain solid I had brought in from VIZ and thus result in a sort of painting the landscape shape with the road and green/vegetation zones, meaning these would have the correct altitude for the area of the terrain they were being placed/drawn in.

However, I stumbled across the fact that when VIZ exports terrains and other 3D geometry back into AutoCAD, it converts it into polyface meshes, with which -- as far as I know -- I can do nothing in AutoCAD; I cannot intersect them with AutoCAD 3D solids, so I cannot make the terrain I created in VIZ interact with my road and green area shapes. I can't even section the terrain object to create profiles.

Since I have no other software to create terrains from contours, does anyone have any suggestion as to how I can paint a 3D landscape object in AutoCAD with roads and other shapes drawn in 2D so as to attain seperate objects for these and be able to put them in different layers, change properties, etc.?


And also, just to get a general notion, what AutoCAD Map 3D or, most probably, Civil 3D features would help me do these tasks I described?
I'm completely inexperienced with either software, but would any of these programs be ideal (and much more efficient and fast) to conduct this sort of work?

Many thanks for any help!
Henrique

[jaberwok]

I've heard that A2007 and A2008 can convert mesh entities to solids (I haven't tried).
M2S.lsp (Google it) can convert some meshes to solids but your terrain map may be rather complex. There is another mesh to solid lisp whose name I can't remember that deals with the mesh types that M2S cannot handle.

[henriquebsoares]

Many thanks! This should prove quite useful, I'll try it right away! Thanks.

[henriquebsoares]

Well, M2S didn't seem to work because it complained my solid was not an "open" mesh.

However I was able to convert the mesh into a solid by exploding it into individual faces and using F2S.lsp to convert those into solids and that proved quite effective and useful, so thanks once more for the tip! :)

Henrique

[albert.ndubizu]

Try saving as a .dwf file, then open in Global Mapper then edit it then back to Autocad

[mmccarter]

Well, M2S didn't seem to work because it complained my solid was not an "open" mesh.

However I was able to convert the mesh into a solid by exploding it into individual faces and using F2S.lsp to convert those into solids and that proved quite effective and useful, so thanks once more for the tip! :)

Henrique

This is the exact same method I have used when forced to out of necesity in the past a few times.

One other opotion might be to use the lfot command on your contours to create a surface in AutoCAD although this will not be of use for colouring parts of it for road/grass etc.
You could then THICKEN the lofted surface which would possibly give you a solid object and thus more manipulation of it and other solid objects.