#ACAD to 3ds help
15 messages in this thread
I am having problems converting complex DXF files from ACAD
into 3ds. I forget the pbject unify, flip etc.. sequence. Could
someone please help? Is there an easier way of isolating those
"missing faces" withgout rendering quesswork? Is there a step missing
in the ACAD export? I meshes the wireframes at solwdens of 8, and 8
subdivisions,s. I then exported with 16 decimal place accuracy, but I
still get those missing faces. The accuracy of my modeling REQUIRES
ACAD. So, anyone who has any ideas, let me know, thanks.
The visibility of faces is related to the direction of creation in
ACAD. CCW point picks will make a visible face. Either pay close
attention when you create the model in ACAD or flip the faces in 3DS,
there are no shortcuts that I'm aware of. Select as many visible
faces as you can in 3DS then use Display/hide/face to narrow down the
work.
Are you using AME? If so, the rules for AME models are different than
for AutoCAD entities – you do NOT unify their normals upon import. As
for other AutoCAD entities the variations vary for the variuos entity
types and can get somewhat involved. What entity types are you
exporting?
The Counter-Clockwise rule for face building is "correct" but is only
relevant for isolated faces. For those that build a mesh it is MUCH
more important for EACH to share two vertices with the adjacent face
– only then will faces unify correctly.
Also, forget the 16-place DXF export. Binary is smaller, quicker, and
just as accurate.
Yes, I am using AME. I have found that if I do not unify normals, the object
imports MUCH rougher. For some reason, smoothing does not work right.
1. Is there a way to import WITHOUT haveing to SOLMESH in acad first? (Takes
SOOOOOO long.)
>>1. Is there a way to import WITHOUT haveing to SOLMESH in acad first? (Takes
SOOOOOO long.)
Afraid not. However you can reduce the time it takes by solmeshing a bunch of
solids at a time instead of all solids in one shot. I have a lisp routine
somewhere that will mesh solids layer by layer. It scans the layer list, then
grabs all the solids on one layer and meshes them. It then procedes to do the
same to all the other layers. It works pretty well.
I'll see if I can find it. I haven't used AME in a while.
Yann Bertaud – VPG, Autodesk.
In addition to what Ted and Phil said, we'll be shipping a new IPAS3
routine at the end of April that lets you visualize all the surface
normals in an object with little arrow/vectors growing out of the
faces. This'll let you see exactly what's going on with the model,
and you can click on the vectors to flip the normals. (This is one
of five things that optmiz.pxp does.)
Hey, OPTMIZ.PXP sounds like a great tool! What are the other four things it
does ? (now that you've got our curiosity up <g>).
OK, here's a list of what Optimize.pxp does (interactively):
1) Object (or selected face) tessellation, with edge tensioning
for tessellation smoothing (at tension values of 25 or
less). (This is exactly the same as Displace's
tessellation.)
2) Mesh optimization, similar to Displace, but with an
additional Bias control for keeping faces from becoming
"slivery".
3) Face Normal visualization and modification, with the ability
to "grow" surface normals from faces and manually click on
them to flip them. (Unify, Flip Element, and Flip Object
are also there for convenience).
4) Text embedding into objects so you can keep notes with each
individual object. This uses the F11 Text Editor as an
integrated component within Optimize.
and, most importantly…
5) Mesh Extracting and Embedding, so you can embed different-
res versions into your object for MSHRES.AXP to extract and
use at render-time. (ie, use a simple version in the Ed/KF,
and then at render-time automatically use the hi-res
version)
Sounds like a great utility!
Abbilities 1 & 5 eliminated two of my wishlist items, and number 4 is one I
never even considered for 3DS (sounds kinda like an AuotCAD block attribute
of sorts). Looks like the text editor is going to have a use after all <g>.
– Phil
Can you also set the length of the arrows in optmiz.pxp, as per
Wavefront?
Absolutely.
– G
Wow, now that's a useful routine, as long as you can adjust the length of the
normal vector. You've apparently been noticing things in SGI-land <g>. Is this
still part of the 2 disk collections ?
BILL
Sure is.
– G
Looking forward to it. How much will the new package run?
Optimize, along with Tempo, Keyman, Hedra2 and Displace will be part of a $300
collection.
– G