#3d Acad entities ->3DS
2 messages in this thread
Wonder if anyone can help me on this one. I just spent eight hours yesterday
beating my head against the wall, doing everything wrong.
I'm trying to take polylines with 3D info, representing rooftops of a city that
is part of an Acad terrain model. I have imported the actual terrain model
minus the rooftops, and now wish to turn the 'rooftops' into buildings by
extrusion in either 3D Studio, or Acad r12.
I imported the polylines into the 3DS shaper, but naturally they lost their
co-ordinates, and were lofted as a flat piece of geometry. I tried to
Quicksurf these onto the terrain model, which represents a small mountain in
the SF bay area, but couldn't get it to lay the buildings on the model.
I then exploded the 3D polylines into 3D faces in Acad12, and turned them into
blocks, with a base point of 0,0,0. When I tried to Quicksurf the blocks, they
still came out flat, not drape onto the contours of the hillside.
Next thing I'll try is to extrude these polylines (rooftops) from the original
Acad model (since the altitude info is already there) and then .DXF that out to
3D Editor. Will Fill-Plines turned on fill the 'roofs' in the extrusions, i.e.
will it close the tops of the Acad extruded entities when they get imported
into 3D Studio?
Thanks in advance…
^.^ John (my head is getting flat from beating the wall) Tissavary
>>I'm trying to take polylines with 3D info…
What do you mean w/ 3D info? Do you mean that they have an elevation (Z)
greater than 0?
>>I then exploded the 3D polylines into 3D faces in Acad12
Again, I don't understand. 3Dpolys are polylines that are not required to have
all their verticies lie in one plane. They can NOT be brought into 3DS except
as paths, as they have zero surface area but are not 2D. Do you mean that
these are 2D polylines that have been extruded?
The easiest thing to do, if I interpret you right is to, in ACAD, take normal
polylines that represent your rooftops (you'll have to use multiple ones for
roofs that have multiple levels cause I don't think you can extrude 3Dpolys),
and extrude them down LOWER than the lowest point on the ground plane! Then,
when you import them in to 3DS and position them over your ground mesh, the
buildings will just continue on through, intersecting the ground. If you feel
the need to actually trim them off, you could make a copy of the ground mesh
(with a different name, but WITHOUT moving it), and then boolean subtract it
from the buildings (remembering to tesselate the buildings first to generate
the required face complexity). The copy will disappear after the boolean, of
course.
>>Will Fill-Plines turned on fill the 'roofs' in the extrusions?
The extruded polylines should be automatically capped.
Is this any help?
Dave