This is a guide on how to set up Blender and the Collada exporter plug-in. You’ll need to follow this guide in order to be able to use my XNA Blender importer.

First you will need to install Blender itself. There are new versions released quite often but at the time of writing, the current stable version is 2.45 and I suggest downloading it directly from the Blender Foundation.

Installation should be simple, just use the defaults but make sure you have the following selected when the installer asks you:

I chose the installation folder of “C:\Program Files\Blender Foundation\Blender” but if you install somewhere else, that is fine – just remember where as you are going to need to install the Collada exporter plugin there shortly.

Next, you need to install Python. Blender requires you to have Python installed as it’s what most of the custom Blender import/export plugins are written in. Blender 2.45 was compiled against Python 2.5 and you need to download and install that too. The Python project releases bug fixes from time to time while maintaining compatibility and currently the latest version of Python 2.5 is actually numbered 2.5.2. If a new version is released, anything matching 2.5.x will do. Just install Python with all the default options.

When you open Blender after this, you will notice that it opens a separate window apart from the main Blender one. In this window you will see the debug output from any Python plugins. If you installed Blender and Python correctly, you should see it confirm that Python has been detected.

Finally, we need to get the Collada Export plugin for Blender. You might notice if you look at the Blender export plugins in the File->Export menu, that there is already an entry for the Collada 1.4 exporter. Don’t use it. It’s the version that comes with the Blender installer and it’s broken. It bombs out when you try to export meshes so you need to get the latest bleeding-edge version from Sourceforge, directly from the subversion repository.

Subversion?

In case you don’t know about it, Subversion is a source-code revision control system which allows developers to collaborate on the same project, checking in their changes when they are happy and updating their local copy to bring in changes from other developers working along with them. I happen to use a Subversion repository at home and at work for my professional and part-time coding projects and highly recommend it. The developers of the Collada Blender export plugin also use a Subversion repository hosted at Sourceforge. To get the latest version of the code, you’ll need to install a Subversion client to connect to and export the code to your local machine.

TortoiseSVN is the de-facto client for Windows and I’m currently running an alpha version of their up-coming 1.5.0 release. If you’d prefer not to install alpha version software, install the most recent stable version from here. I’m using this one but the instructions are the same, you just need to be aware that my screenshot will differ from yours cosmetically.

Once you have installed TortoiseSVN and rebooted, browse to the Blender installation folder. Remember, the default is “C:\Program Files\Blender Foundation\Blender\”. Then navigate to the .blender folder in there to find where all the plugins live. Right-click on the “scripts” folder and choose the option “TortoiseSVN->Export” from the context menu that pops up.

In the “URL of repository” text box, put this:

https://colladablender.svn.sourceforge.net/svnroot/colladablender/trunk

Then select the “Immediate children, including folders” option from the dropdown. It should look like this:

Hit ok and it will export the latest version of the plugin, directly from the source-code repository the developers use, into your machines Blender plugin folder. It may be slow, and do not be surprised at data transfer rates of 1k/s – luckily the plugin is very small. If it asks you if you are sure, confirm your paths are exactly as in the image above and hit yes.

You are now ready to launch Blender and start exporting Blender models into Collada files!

To do this, go to the File->Export menu in Blender and choose “COLLADA 1.4″ and be sure to select the options in the image to the right, to avoid any errors.

Choosing to export to triangles is important as Blender allows you to model using quads which, while great for modelling, is not much use to hardware rendering code which requires geometry to be passed as triangles.

Disabling physics is important as the ability to export this is still under development and will cause an error if you do not disable it.

It will export the files with a .dae extension. Visual C# Express will still display it as an XML file with collapsible nodes to make browsing it easier. It also helps identify the file when added as content in an XNA project as the BlenderXNA Content Importer is setup to be automatically applied to .dae files by default.