Friday, October 17, 2008


I visited a well known architectural practice this week who specialize in freeform organic architecture. They  had asked me come in to present Revit Architecture 2009 to see how they may be able to incorporate into their workflow. However, in our discussions about software that they currently use they advised me to take a look at an application called TopMod. I wrote down the details and Googled it when I got home.

This is an amazing application! As the website says "TopMod3d is a free, open source, portable, platform independent topological mesh modeling system that allows users to create high genus 2-manifold (watertight) meshes". I knocked this up in about 2 minutes!


Agreed its not Revit, but I would certainly recommend you take a look if you like creating organic forms within a computer environment. TopMod has limited export capabilities, but I was able to save the file in .obj format and was then able to import this into 3dsmax.


I then exported the form from Max as a DWG and was able it import it into a Revit mass family. This is only a mesh, so you won't be able to cut floor plates from the mesh.


Quick draft render in Revit......



Jon Stamps said...

No way to import as a solid mass?

dave morris said...

I received this blog post in a Google Alert, and I just wanted to say thank you so much for using TopMod3d! I am one of the lead developers of the most recent version, which I did for my graduate thesis research project at Texas A&M University.

I am kind of curious if this well known architecture firm you are talking about is the one I am thinking of. If it is, please email me and let me know. I interviewed with some of those organic building designer types at a firm in the UK, and after the first phone call they wouldn't even give me the time of day.

I'm also kind of curious what they are using TopMod3d for. We are working on a new version, and we are always looking for new ideas about features and functionality. Thanks so much for your help,

dave morris

dave morris said...

What program are you trying to import into? What file formats does it accept?

Unknown said...

Dave, I think Jon is asking if it is possible to import a TopMod form into a Revit mass family. Ideally you need to be able to bring the form in as a solid rather than a mesh. You than have the ability to slice the solid mass to get areas of the mass. Do you think it would be possible to turn the mesh into a SAT file?

dave morris said...

I am not really familiar with the SAT file format. The formats I know for sure that I can convert topmod .obj files to are ASCII STL, Binary STL, PLY, OFF, PTS (point cloud files?), and ASCII DirectX files (.x). These conversions can all be done with a program called MeshMan.exe. I have also used TopMod obj's in Maya, 3d Studio Max/Viz, etc... and any program that imports .obj files. I'm sure there is a program out there that can import .obj's and export SAT files.

I'm not sure which programs really support the SAT file format, and what is really unique about it. I read the format specification and it seems pretty straightforward, but I wanted to find another tool that does it before I try it myself.

Matt said...

Hi, we just had a user post on our forum his results of converting a TopMod mesh to T-Splines, then to Rhino. T-Splines is NURBS compatible, so any T-Spline surface can be exported as an iges, step, or anything else that Rhino exports.

You can get a free trial of the T-Splines Rhino plugin at

The forum post about TopMod is . This example is jewelry, but of course the conversion works for any mesh.

rycdesign said...

Hi David, I visited HOK Sport a few years ago in Kansas City. Very cool. I love the new Twins Stadium here in Minnesota.

Please help me out, I've been trying to figure this out for ages.

Could you please explain the process of exporting a patch obj from TopMod to 3ds Max? I am trying to render some models I have made for my portfolio and can't seem to get it right.

When I try to import in Max 2012 there is nothing there, or it crashes. I've tried SketchUp and Rhino4 too. I've tried every export option or workflow I can think of, even Meshman like Dave suggested with no luck.

Just to clarify, I am able to import the straight obj, but not the patch obj. If you press 6 in TopMod for render type you'll know exactly what I mean.

Thanks a lot in advance for helping me out!

Ryan Andrews