Export Your Sketchup Model into FSX
By Larry Robbins (3 February 2011)
Modeling buildings for FSX can be both fun and frustrating at the same time. However, everyone who enjoys Flight Sim flying likes to fly in a familiar place and within an environment that is as real and as accurate to the real world as possible. So whether you simply want to fly over your house or recreate an entire virtual community, I am going to show you how you can use Google's Sketchup modeling program to export your model into FSX. Google Sketchup is both easy to use and fun. The learning curve is not as difficult as most other 3D modeling programs, and in conjunction with a few other tools, exporting to FSX is not that difficult. But best of all, Google Sketchup is FREE! And as an added bonus, there are literally thousands of models within the Google Warehouse that have already been created. Some require a little tweaking in order to play nice with FSX, but it will save you a lot of time. There are several steps involved, but I will guide you along the way. So let's get started...
Create your model or download one from the Google Warehouse
For the purpose of this tutorial, I will not go into detail about creating a model in Google Sketchup. There are many tutorial videos online if you need help getting started. If you have never used Google Sketchup before, than take a look at the video which will show you how to get started. It will explain how to use some of the more basic tools available for use in Google Sketchup and how to create a simple building from scratch. Also, be sure to check out Building Maker and the Google Warehouse for more advanced users.
Above is a model of the Washington Monument Bookstore that I created using Google Sketchup that I wanted to add to my WashDCX scenery project since it was missing from the default FSX scenery. I took pictures of the real building and added them as textures to my Google Sketchup model. You can do the same for your project, or you may be able to find pictures on the internet. Another new and exciting way of adding textures is through Google's Building Maker program that easily integrates into Google Sketchup. You may also find that the building you want has already been created in the Google Warehouse, so be sure to do a quick search.
I will take a moment to give you one quick tip about building textures. The fewer the textures, the better. Too many textures will create too numerous Drawcalls for your model once you place it inside FSX and may affect game performance. It is best to create one single texture sheet for all of the textures you use in your building to reduce the number of Drawcalls your model will have after import into FSX. For a more detailed look on how this is done, check out the following articles about model textures here on the FSDeveloper.com wiki page.
Export Your Model As A COLLADA File (*.dae)
Now that your model has been completed in Google Sketchup, you will want to export it into a format that we can use in FSX. This will be done in several steps, but the first step is to save the model as a COLLADA or .dae file. To do this in Sketchup, go to File ----> Export ----> 3D Model. On the drop down menu for Export Type, choose COLLADA File (*.dae). This will be a temporary file, so save it wherever you choose. I put mine on the desktop for quick access since I will later trash it anyways.
Import Your (*.dae) File Into ModelConverterX
After you have exported your model from Google Sketchup to a COLLADA File (*.dae), two separate files will be created. One is the name of whatever you called your file with a .dae extension. In my example it would be WahMont Bookstore.dae. The second file created will contain all of the textures used in your model and is simply called WahMont Bookstore. You can click to open the texture folder if you wish. Inside, you will see texture files labeled texture 1, texture 2, and so on. In order to convert the .dae file into something that FSX can use, we will be using another program called ModelConverterX. You can download it here for free. Once you have downloaded and installed ModelConverterX, simply drag the .dae file into the program window. It may take a few moments for the import process to complete. Once it does, your model will appear in the main window complete with textures. For a Video Tutorial by the author on how to use ModelConverterX, click here. Thanks Arno for giving us this handy little tool.
Minimize Drawcalls and Update Texture File Names
Remember how I said earlier that the fewer textures you have, the less the number of drawcalls used by the model? Well, ModelConverterX has a feature called Minimize Drawcalls that will try to combine some of your textures into a single texture sheet. This will help to improve game performance later on. The next thing we need to do is update the texture file names. To do so, you will need to click the Mass Texture Editor button. Notice how I replaced the word texture with something I can easily identify with later. Now, before hitting the Update button, be sure to save the NEW texture files into the SAME folder as your original texture files. You may need to change the pathway.
Export to FSX MDL Object (*.MDL)
Before closing the ModelConverterX program, we need to save our model to a format that FSX can use. For FSX, that format will be a MDL file. ModelConverterX also has the capability of saving into an FS2004 format, an object X format, and several other options used for various other 3D modeling programs. Save the .MDL file wherever you wish. I keep all of my .MDL files together in one single folder.
Move Your .DDS Texture files to your Texture Folder in FSX
As you may recall in step 4, we changed the name of our texture files and saved them into the original texture folder that was generated by Google Sketchup in Step 2. Now, navigate back to and open the texture folder. You will now see a list of .dds files as well as the original texture files, which are in .jpg format. We will no longer be using the original .jpg files, so you can trash them if you wish. In order for FSX to be able to use the new .dds textures for your model, you will need to move them to the appropriate texture folder inside FSX. In my example, I have created a new scenery folder under Microsoft Flight Simulator X ----> Addon Scenery ----> WashDCX. This new WashDCX file contains two sub folders: Scenery and Texture. The Scenery folder is where our .BGL file will live. We will create the .BGL file in the next step. But for now, you need to drag all of your .dds texture files into the new Texture sub folder. Place any new .dds texture files from any other models associated with this project here as well. Now, FSX knows where to find the appropriate textures for your model.
Add Your .MDL model to a Library and Create a .BGL file
When you download and install ModelConverterX, it will automatically add an additional program called LibraryCreaterXML. There are also other third party programs that will do the same thing. Open up the LibraryCreaterXML program and choose File ----> New Library. Choose a name for your new library and save it in a safe place as a (*.xml) extension. Once your new library is created, you need to add the .MDL file that you exported in Step 5 to your library. Choose Add MDL objects and navigate to your .MDL file and choose open. The name of your model should now appear within the main screen. After you have added all of the .MDL files that you want to appear within the same project, then choose File ----> Save Library. More can also be added later. At last, we need to create a .BGL file for FSX. Choose File ----> Compile library BGL. File Name should point to the Scenery sub folder we created in step 6 and be called whatever you wish. In my example, the file path would be: Microsoft Flight Simulator X\ Addon Scenery\WashDCX\scenery\WashDCX_objects. The LibraryCreaterXML program will create a new file called WashDCX_objects.bgl and place it into my Scenery sub folder.
Placing Your Model Into FSX
For the final step, you will need to physically place your model into FSX. There are several programs to choose from for this task. Explanation of how to use each of these programs are extensive and beyond the topic of this tutorial. A free program available for download is SBuilderX by PTSim, although there is a bit of a learning curve to master if you are using it for the first time. Another free program is Scenery Shortcut by Abacus, which I have not personally used. I actually prefer a payware program called Instant Scenery 2 by Flight1. It is available as a direct download from their site for $29.95. I prefer it because of its simple and easy to use interface as well as the ability to place objects live while slewing in FSX. Please let me know of any other programs worth mentioning that I may have not included.
For further discussion, questions, comments, or suggestions concerning this tutorial, please visit my Forum page. It's free and quick to register and you can start your own discussion topic. Also, feel free to drop me an email anytime.