====== Lab 2: Getting Meshes and Materials into Ogre 3D ======

===== Required Tools =====

  * [[http://www.blender.org/|Blender 3D]] modeling and rendering environment, use the latest version
  * [[http://code.google.com/p/blender2ogre/|Blender2Ogre]] Plug-in for Blender 2.5 and above
    * Download the file [[http://code.google.com/p/blender2ogre/downloads/detail?name=blender2ogre-0.5.5.zip|blender2ogre-0.5.5.zip]]
    * Run Blender and from **File->User Preferences...** choose the **Addons** panel and click the **Install Add-On** button. Navigate to and select your downloaded ZIP archive. 
    * Once Blender has processed the ZIP file you should see the exporter listed, but grayed out. Check the check-box next to it to activate it.
    * Now you can run the exporter from the Blender **File->Export** menu (pick the Ogre 3D export) and make sure that the object you want to export has been selected in the 3D scene.
  * Make sure that the **OgreXMLConverter.exe** (or OgreXMLConverter_d.exe) is in your executable system path, you will find this tool inside your **built** Ogre system in a folder called **bin\Release** (or **bin\Debug**)
 

===== What to Do in this Lab =====

==== The Procedure ====

  - Go to your personal Ogre application folder (where the executable for your own Ogre application sits) and do the following:
    * Create a new sub-folder called **Models**
    * Add the line **FileSystem=Models** in the **Popular** section of your application's **resources.cfg** (This tells your application that it should search for named resources in this folder)
  - Create a model in Blender (even just use the default cube you get when you start up Blender)
    * There is a lot of good resources on Blender modeling, including the [[http://www.blender.org/education-help/tutorials/getting-started/|Official Getting Started]] tutorials  
    * It is a good idea to save your model in the Blender file format early and often  
    * Pay attention to what you name your geometry, this becomes the name of the exported mesh
  - Export the model using the Blender2Ogre exporter and save it in your **Models** folder
    * Make sure that any texture imported, baked or generated is saved as a file in the same folder
  - Run the **OgreXMLConverter** command line tool on the exported **XML** mesh file to turn it into a binary Ogre **mesh** file
  - Create an **Entity** in your Ogre application from the mesh you just exported
    * In C++ it would look like this:
        <code cpp>        Ogre::Entity* mycube = mSceneMgr->createEntity("MyCube", "MyCubeMesh.mesh");
        Ogre::SceneNode* cubeNode = mSceneMgr->getRootSceneNode()->createChildSceneNode();
        cubeNode->attachObject(mycube);
	cubeNode->setScale(50,10,50); // You may have to scale your object to see it well</code>  
  - Make sure you see your object when you run your application! 

==== What to Try ====

Here are things you should now play with:  
  * Open up your exported **mesh** **XML** file and make sure you understand its structure
  * Try changing values inside the exported **mesh** **XML** file and observe the changes in your Ogre application, but remember to run the OgreXMLConverter again!
  * Notice that inside the **XML** file the submesh refers to a **Material** by name, find the corresponding ** *.material ** file in your model folder (it got exported along with the mesh XML file) and read through it. This is the material that Ogre reads in along with the mesh.
  * Try changing values of the material (e.g. the diffuse values) inside the exported material file and observe the changes in your Ogre application (you do not have to run the OgreXMLConverter again for this, the material is already in the right format)
  * Create a new material inside the same material file, by copy-pasting the material definition and changing its name (e.g. into **BlueMaterial**) and give it different values (e.g. making the diffuse color blue). 
    * To test this new material, you can simply assign it to any entity in your Ogre application with the **setMaterialName** method like this: 
  <code cpp>    myCube->setMaterialName("BlueMaterial");</code>
  * See if you can create several entities from your original mesh, but assign different materials to each of them