Converting Sketchup Models to 3DS

If you have tried to create models for your 3D games, you probably know that many modeling programs out there (like autodesk) are quite expensive, and have so many features that using them feels like drinking out of a fire hose. One of the simplest modeling programs to use (in my opinion) is Google Sketchup (http://sketchup.google.com/). It doesn't have a lot of the features of some of the other modeling programs available, but it is more than sufficient for most models you will want to create. There is even a "3D Warehouse" full of Sketchup models available for download(http://sketchup.google.com/3dwarehouse).

Only problem is, the free version does not export your model into a common format (like 3ds). So I figured out a way to do the conversion.

The first important piece of information I found, is that KMZ file format is actually just a ZIP file. If you export your sketchup model to "Google Earth 4 (*.kmz)", you can change the name of your file from filename.kmz to filename.zip and look inside. You will find a model file in there, of the Collada "Digital Asset Exchange" format. It has the extension ".dae".

Once you have your .dae file, you will, of course need a converter to change it to a .3ds file. I found a converter that will do this for you. It is called the FBX converter tool, on the autodesk website.

You can download the windows version of the FBX converter from:
http://images.autodesk.com/adsk/fil...nverter_win.exe
The program will install to the following location (unless you specify otherwise):
Program Files\Autodesk\FBX\FBXConverter\2006.11.2\FbxConverterUI.exe

I also saw a mac and and a linux version of the converter (I forgot to grab the links while I was there - you'll have to search the autodesk site if you aren't running windows).

Now the FBX converter will convert your .dae file into a .fbx file. From there, the FBX converter will let you convert the .fbx file into a .3ds file.

This converter also supports a few other formats, so it could be pretty handy to have around.

Here is the process for converting from .skp to .3ds:

1) Download or create a .skp model in Sketchup
2) In Sketchup, export your model to "Google Earth 4 (*.kmz)
(note: be sure to choose version 4, because the other one is different)
3) Change the extention of the kmz file to .zip
4) Pull out the .dae file
5) In FBX Converter, convert the .dae file to .fbx
6) In FBX Converter, convert the .fbx file to .3ds

The only other issue I had (probably specific to the model I was using), is a couple of the materials were not compatible with jPCT (transparency issue). I used a free program called LithUnwrap (http://www.sharecg.com/v/5169/softw...per-for-Windows) to edit the materials in the .3ds model I was using. Lithunwrap works great for this, but it does have a maximum number or polys it will load, so there are probably better programs out there for editing materials. You may not have to worry about that though, if you don't use transparency in your models. I made an applet that loads the skp model I converted:
http://www.paulscode.com/source/LegoCar/
(Use the mouse to rotate the object)

You can get the source code at:
http://www.paulscode.com/source/LegoCar/LegoCar.java
http://www.paulscode.com/source/LegoCar/LegoCar.3ds
(In this demo applet, the 3ds file needs to be compiled into the jar)

And to show that I actually converted that model, here is the original Sketchup file:
http://www.paulscode.com/source/LegoCar/LegoCar.skp

After trying to track down a problem someone was having with this conversion method (on a different forum), I discovered that the FBX converter is not compatible with all .dae files. The solution would be to find a different converter program that converts .dae files to another format, but after some searching, I haven't been able to find a free one. So the above method for converting sketchup files does not always work.

I'll post an update if I find a better way.

Hi Paul.

Indeed, at first, I was able to convert some DAE's from Google Sketchup to 3D Studio properly using the procedure well described by you, but I'm not longer getting that . My last KMZ files contain DAE's whose the conversion to FBX are being impossible.

I'm just wondering if it was a intentional modifying in last version of Google SketchUp by Google team to avoid a conversion without Sketchup Pro.