PDA

View Full Version : Clean conversion of DXF/DWG to Lightwave possible?



bgolden
07-12-2006, 07:53 PM
I've looked through different threads and haven't found a solid answer to converting DXF or DWG for use in LW Modeler. Any files I get from architects end up in an awful, triangulated mess. For the amount of work it would take to clean these up, I'd be better off building them in modeler from scratch. Problem is, these guys are trying to save money by not building the same thing twice.

I'm trying Accutrans and demo version of Polytrans, but getting same mangled mesh. These apps have a bit of a learning curve, so maybe I'm not setting things up right. It would just be nice to find a solution that would convert these files with minimal effort.

Help!!! Any ideas?

Mr_Bester
07-12-2006, 08:23 PM
Everything I have tried is a mess. LWCad 2.0 is now out and it is supposed to do DXF and DWG import, I don't know how well, but the rest of the tools are worth it if nothing else.
Dug

SP00
07-12-2006, 08:45 PM
LWCAD2 is your answer.

robk
07-12-2006, 09:38 PM
I'm trying Accutrans and demo version of Polytrans, but getting same mangled mesh. These apps have a bit of a learning curve, so maybe I'm not setting things up right. It would just be nice to find a solution that would convert these files with minimal effort.

Help!!! Any ideas?

I have used Accutrans for 12 years and it works great for me.
The mangled mess you talk about may be related to where your Autocad model is located. In plan view move all your drawing information close to the origin 0,0,0 point.(this is very important) I usually put the 0,0 point at the corner of the building I am working on. If all the drawing elements are way off the 0,0,0 point in Autocad you will have the problems you mentioned.
- Also remember to save out as a version 12 DXF file and make sure you save objects only!! after you type in dxfout and hit return make sure the file type at the bottem is listed as a ver 12 dxf and in the tools dropdown on the top left of the requester drop down to options and click on the DXF Options tab and put a check in the select objects box.
I have been Talking to Wayne (Accutrans's programmer) and he is trying to get some videos up on using accutrans.

Also remmber if you use solids you need to ouput those layers as .3DS files.

Contact me at [email protected] if you need more help.

MicroMouse
07-12-2006, 10:19 PM
You can email the DXF file to me at [email protected]

You can email the DWG to robk at at [email protected] as he has AutoCAD and I don't and I will look at it when I visit him tomorrow.

When you read the DXF file into AccuTrans, does the drawing look okay?

If the drawing looks okay, use the "Tools->Adjust Object" menu command and a new group of tools will appear in the "Tool Palette" to the right side of the view window.

The "Min-Max" group of edit boxes shows the bounding box that surrounds the drawing. If the drawing is far from the origin it can be adjusted here. Click the "Set Min at 0,0,0" button and the origin will be placed at the lower left corner of the drawing. This will be okay for a test.

When you save to the LWO file in the "Save Object With Options" dialog box, set the "Output Scale Factor". The unit of measurement in the LWO file is a meter. The unit of measurement in the DXF file can be anything. If the DXF file used millimeters, set the scale factor to 0.001.

Wayne

RedBull
07-12-2006, 10:42 PM
I believe you can download the demo for Solidworkd Rhino.
It will allow 25 conversions in the demo version.

I believe LWCAD2 only allows .DXF import/export.
(it's likely better than LW's own, but LW or LWCAD definately need a DWG importer/exporter too)

Also there are of course tools to untriple polygons that come in trippled.
So you might want to untriple or mergetrigons, followed by selecting the non-planar polys and just using triple on those non planar polys. Lightwave also has some polygon reduction tools which can help too.

But i know many people who just use the dxf as a template and rebuild it too.!
LWCAD is excellent for such things.

Mr_Bester
07-13-2006, 06:29 AM
...

Also there are of course tools to untriple polygons that come in trippled.
So you might want to untriple or mergetrigons, followed by selecting the non-planar polys and just using triple on those non planar polys. Lightwave also has some polygon reduction tools which can help too.

....

Unfortunately, the last dxf I brought in(through a different program) was tripled in an unnatural way. On a curved object, the tris shared a point at the lower left corner and "the fat part" went across the top. And the opposite on the bottom. I've decided to let the AutoCad guy stick with Viz, even though, if the model came into lightwave decently, I could get it textured and rendered in 1/10th the time.
Dug

Dodgy
07-13-2006, 06:44 AM
There's some good tools for sorting out nasty triangulations.
http://www.intramail.ru/~dex/lwplugins.html

I definitely recommend edge relax.

bgolden
07-13-2006, 08:32 AM
Thanks all for the input. I will try everything, then post results back here.

- Brad

MicroMouse
07-13-2006, 02:55 PM
One problem with the 3D model of a Gazebo in the DXF file was that the model was located too far away from the origin and LightWave could not display the model correctly.

Either moving the model closer to the origin in AutoCAD or relocating the origin in AccuTrans solved this problem.

Another problem was that part of the model was made using SOLID entities which AccuTrans does not support so part of the model was missing as it was not converted. The solid entities were exported from AutoCAD using the 3DSOUT command to 3DS files. The 3DSIN command was used to read the 3DS files back into AutoCAD and then the solid entities were deleted.

Wayne

-EsHrA-
10-28-2006, 10:05 AM
hey guys i have a little problem, accutrans loses a little bitt of information when loading the dxf12 (dwg converted with acme cad converter).
a few windows (4 or 5 out of ~60) for example, dunno why, when i load the dxf12 again into acmecadconv. the info is still there.
anyways, i found out that dstorms dxf2import imports all the stuff i need including the important windows only allot of the data comes in as rounded curves (think smurfs house..) which only should be straight lines.

so, my question is how do i convert these simple curves back to straight lines in lw?

dumb quesion?

hope to get sum answer soon.... hehe... im waiting :)


mlon

MicroMouse
10-28-2006, 01:03 PM
hey guys i have a little problem, accutrans loses a little bitt of information when loading the dxf12 (dwg converted with acme cad converter).
a few windows (4 or 5 out of ~60) for example, dunno why, when i load the dxf12 again into acmecadconv. the info is still there.


If you want to, you can email the DXF file to [email protected] and I will check out why the windows are getting lost.

Include a screen shot from acmecadconv and mark the location of the lost windows.

Wayne

MicroMouse
10-31-2006, 08:28 PM
Lost Windows Problem:

Instances are known as blocks in AutoCAD. Blocks can be inserted in a block which can be inserted in a block which can be inserted in ...

Some time ago the block handling routine in AccuTrans was changed. One step was missed which caused some data to be lost when inserting blocks.

This problem has been fixed. If someone needs the fix for blocks before the next version is released, email me for a copy of a beta version.

Wayne