Questions to SDF, urdf, xacro, material, textures using Gazebo

edit

Found the way to do it. This works for me:

Well in the package.xml you need:

<run_depend>gazebo_ros</run_depend>

<export>    
  <gazebo_ros gazebo_media_path="${prefix}"/>                             
</export>

${prefix} == package directory

and the folder structure is like this:

• media
  • materials
    • scripts
    • texture

in the xacro file:

<gazebo reference="link">                           
<material>YourMaterial</material>
</gazebo>

I guess in the process I changed the folder structure multiple times, maybe I first missed the media folder.