remove divide by 2 when writing boxes to collada format

[jacquelinekay]

Potential fix for #132

@skohlbr, do you think you could build robot_model from source and see if this fixes your problem?

[scpeters]

I think this makes sense because both the box objects in both urdfdom and geometric_shapes store the box dimensions as the full side lengths (as opposed to bullet, for example, which stores the half side lengths).

[scpeters]

+1 pending confirmation by testing

[jacquelinekay]

While thinking of an automated test for this PR, I realized that the test for this package was commented out by the previous maintainer and makes nonexistent API calls:

https://github.com/ros/robot_model/blob/kinetic-devel/collada_urdf/test/test_collada_urdf.cpp#L37

So, I'm going to look into better test coverage for this package. If that takes too long I'll test it manually, merge this into Indigo/Jade/Kinetic, and release.

[jacquelinekay]

I tested this manually because restoring the tests for collada_urdf is going to take a while, with a simple box and sphere example. (https://gist.github.com/jacquelinekay/8f667d7d6f603c21534afab0bc1c8626)

The scaling looks better in meshlab with this PR, but the sphere disappears.

I have no idea why that would be.

[jacquelinekay]

update: The disappearing sphere is only when robot_model is installed from source, not debs. And the sphere problem exists on indigo-devel.

[clalancette]

So, I ended up testing this out on both Indigo and Kinetic, and after Jackie's patch, things look much better in both. Visualizing Jackie's test URDF in RViz now looks the same as visualizing the converted DAE file in meshlab. So given that, and Steven's OK of it, I'm going to merge this to Indigo and Kinetic.

[jacquelinekay]

Thanks ^_^