Hi. I’ve used AutoCAD, 3D Max (or was it 3D Studio Viz?), and LightWave 3D about 10-15 years ago and have decided to get back into 3D modelling and animation.

I’ve just downloaded Houdini FX Apprentice 13 for Mac and I’m having trouble importing geometry from a DXF file created by AutoCAD 2014 for Mac. Nothing shows up and when I double click the node to see what’s in it, it has a file icon with red diagonal stripes in the background.

I’ve tried the R12, 2000, and 2004 versions of the DXF format. I started with a version that has a 3D object created by revolving polylines. But now all I have are basic arcs and lines on a flat plane.

Maybe the scale is the problem? I’m designing a rotating space station (like in the movie Elysium) and the geometry is 10,000 units (meters) wide and offset from the WCS origin by 64,000 units.

I’ve tried importing the revolved 3D version into Maya. That sort-of works. I think I just need to tidy up the profile before revolving it.
However, I’m really interested in Houdini. Its particle effects and its procedural workflow sound interesting. So I want to see if I can get a workflow from AutoCAD to Houdini, even if I just use AutoCAD to create basic profiles with no 3D objects.

I supposed I could learn how to create the model completely from scratch in Houdini, but I really like how AutoCAD works for creating profiles because of its object snap/tracking and the ability to easily work in large scales etc.

Also, Houdini won’t display files properly. Numbers in filenames are replaced with “$f”, with the number in brackets off the end of the filename. And even more bizarre is if I have a filename with number dash number (such as 20-2), it won’t even show up. I know all these 3D FX and CAD programs have their own interfaces and dialog boxes, but this seems like it’s broken.

Any advice would be appreciated. Perhaps I’ll need to download 3D Max, too? I’ve heard that can work as a go-between for AutoCAD and other apps.

Try exporting to .obj and then importing that into Houdini.

edward
Try exporting to .obj and then importing that into Houdini.

I don't see any .obj in either export or save as.

3DS Max so far has been great for importing CAD data because of Direct Connect. However if you want to skip this step (and Autodesk) you may want to check out Polytrans. These both would be for getting .objs for import into Houdini. I don't know if AutoCAD (never used it) has an export as OBJ natively. Rhino3D is another great option to explore for actual modelling and importing of CAD data.

But even then, I've never had much luck with DXF's, it's usually been STEP, STL or IGES files for the actual 3D information. Whereas DWG and DFX have been just for curves.

For the $F problem on the file dialog, there should be an option in the pop up to uncheck “Show sequences as one entry”.

Gyroscope
3DS Max so far has been great for importing CAD data because of Direct Connect. However if you want to skip this step (and Autodesk) you may want to check out Polytrans. These both would be for getting .objs for import into Houdini. I don't know if AutoCAD (never used it) has an export as OBJ natively. Rhino3D is another great option to explore for actual modelling and importing of CAD data.

But even then, I've never had much luck with DXF's, it's usually been STEP, STL or IGES files for the actual 3D information. Whereas DWG and DFX have been just for curves.

For the $F problem on the file dialog, there should be an option in the pop up to uncheck “Show sequences as one entry”.

Thanks. One problem with 3ds Max and Rhino3D is that they're Windows only (well, Rhino does have an experimental version for OS X, it seems). I already have Bootcamp for gaming, but that's a pain for work. Maybe I'll have to bite the bullet and install Parallels or Fusion.

So you think Houdini should be OK importing DXFs that are just plain lines and arcs? Perhaps it's the large scale I was using that is throwing it off?

Polytrans looks interesting. Do you think it's a good tool to have for someone playing around with all these packages, or is it more specialist software?

In general I find creating asset items around the origin to be the safest. When you're in your scene layout phase then you'd probably translate an object. So your model being 64000 units away from the origin in AutoCAD may be a problem but I have no real experience with AutoCAD. I've had some DXF files load (no errors) but nothing show, and others show curves. It probably depends on the export settings.

Does AutoCAD have the option of exporting IGES or STL? These are more widely accepted. I think STEP is a SolidWorks file format. With Polytrans, try it out, they have a demo, and see if it works for you.

Gyroscope
In general I find creating asset items around the origin to be the safest. When you're in your scene layout phase then you'd probably translate an object. So your model being 64000 units away from the origin in AutoCAD may be a problem but I have no real experience with AutoCAD. I've had some DXF files load (no errors) but nothing show, and others show curves. It probably depends on the export settings.

Does AutoCAD have the option of exporting IGES or STL? These are more widely accepted. I think STEP is a SolidWorks file format. With Polytrans, try it out, they have a demo, and see if it works for you.

I want to keep it at 64,000, as that is the distance from the origin that I need to revolve the profile around. The whole drawing does have lines going right from the origin to 64,000, so it's not totally empty around the origin and I've tried importing the complete drawing, too.

I managed to revolve the profile in Maya, then tried exporting using the 3 options at the bottom: SPF_DCE, STL_DCE, and IGES_DCE.

The IGES wouldn't work (I think it either gave an error or simply didn't create a file), but it does save a file if I create a new file with a simple object.

The STL saves an empty file, even with a simple object like a native Maya cylinder. And I made sure I used “export all” each time.

The one that did work was SPF/.wire. It didn't work the first time, but I might just have made a mistake the first time.

AutoCAD does have an STL option (called Lithography) but it asks for “solids or watertight meshes”.

You were trying to export the models from Maya using DCE, STL, and IGES?

If you have it in Maya looking how you want, from there you can either use FBX, OBJ or Alembic to get them into Houdini. From AutoCAD straight to Houdini, I'm afraid I've no more insight to give as I use 3ds Max to import STEP, STL, or IGES files first.

Your initial notion of learning to model what you want in an non-engineering DCC app may be the best option. But it depends on what exactly you want to make and how you want the final product to be.