MORSE on OSX using Homebrew

Installing

Tonight I installed and ran MORSE (up to the first tutorial at least) under OSX. This was done using Homebrew. The steps I took were as follows

1. Download Blender from the Blender download page, and copy the apps to /Applications. I used Blender 2.67a 64 bit.

2. As that Blender uses Python 3.3.0 you need to install the exact matching version for your system. I did this using Homebrew. You have to go through some extra steps as the current version of Python is 3.3.1. The hash for the checkout command comes from brew versions python3.

$ cd /usr/local
$ git checkout 864e9f1 /usr/local/Library/Formula/python3.rb
$ brew install python3

Then make sure pkg-config can find this install

$ export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/Cellar/python3/3.3.0/Frameworks/Python.framework/Versions/3.3/lib/pkgconfig

I also had to remove my Python 2.7 packages from my environment as cmake failed:

unset PYTHONPATH

3. I installed MORSE using the manual installation instructions. However, I needed a bit of a hack to get this working. First, the compiled Python modules wouldn't link against the Python libs, so I edit line 261 of config/FindPythonLibs.cmake to be the following

TARGET_LINK_LIBRARIES(${_NAME} python3.3m)

There's probably a more elegant way of fixing this, but I didn't look for it. I then ran ccmake as follows

$ mkdir build && cd build
$ ccmake -DPYTHON_INCLUDE_DIR=/usr/local/Cellar/python3/3.3.0/Frameworks/Python.framework/Versions/3.3/include/python3.3m -DPYTHON_LIBRARY=/usr/local/Cellar/python3/3.3.0/Frameworks/Python.framework -DBUILD_ROS_SUPPORT=ON -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/opt/morse -DPYTHON_EXECUTABLE=/usr/local/bin/python3.3  -DCMAKE_MODULE_LINKER_FLAGS=`pkg-config --libs python3` ..
$ sudo make install

4. To allow MORSE to find Blender I set MORSE_BLENDER as follows:

$ export MORSE_BLENDER=/Applications/blender.app/Contents/MacOS/blender

5. At this point morse check should succeed (despite some minor Blender complaints), and you can run the basic tutorial:

$ morse run /opt/share/morse/examples/tutorials/tutorial-1-sockets.py 

and in another terminal

$ telnet localhost 4000

followed by

id1 atrv.motion set_speed [2, -1]

This should make your robot go in a circle in the simulation.

ROS Integration

Although the above worked for me, I couldn't run the CS sim with ROS integration. This seemed to be because Python 3 couldn't load some of the installed Python 2.7 packages (I installed ROS from source following instructions here). To fix my issues I had to do the following

$ pip3 install PyYAML rospkg catkin_pkg

I have then been running with the following PYTHONPATH (the first seems necessary as the ROS install doesn't do things quite right).

$ export PYTHONPATH=/opt/ros/groovy/lib/python2.7/site-packages:/usr/local/lib/python2.7/site-packages

I also had to change strands_sim/morse_config.py so that the first line launches python3 from the location Homebrew installed it, i.e.

#!/usr/local/bin/python3

I suspect there's a more elegant way of doing this.

Current Issues

The rendering of Blender/MORSE seems a bit odd on my 15" rMBP as I only see the simulation in a quarter of the window. This problem goes away when running on an external display though. Logged here: https://github.com/laas/morse/issues/383

Problems

If you see an error like the following

Traceback (most recent call last):
  File "/opt/bin/morse", line 825, in <module>
    args.func(args)
  File "/opt/bin/morse", line 645, in do_check
    check_setup()
  File "/opt/bin/morse", line 275, in check_setup
    blender_prefix = os.path.join(os.path.normpath(prefix), os.path.normpath("bin/blender"))
NameError: global name 'prefix' is not defined

it means that MORSE can't find Blender. Set MORSE_BLENDER as above.