This month has been, unlike the last one, rather eventful!

Besides many improvements described in the nerd stuff section below, we’re a week or two away from finally launching a testing instance for Crimp, a climbing gym near Heidelberg, Germany – the code that produces the models is in a relatively mature state, with most of the work being spent on UI/backend.

Once the instance is up and running, we will put up a separate post that will go into more detail 🙂.

Nerd Stuff

Quoting last month’s update:

From the progress that was made, it was running into different kinds of bugs on the new data, like different handling of EXIF metadata wrt. image rotation (inconsistently handled/ignored), which breaks segmentation.

Resolved (and re-implemented to not be as fragile)!

Most importantly, the current approach of sparse reconstruction for rebuilding the boulders is flawed – at the moment, we first perform a sparse reconstruction and then align it to another one, which doesn’t work since while the local geometry will be similar, there will be great differences the further apart you look.

Implemented (although this was not as simple as we thought). The alignment now works much better and, due to the rewrite, also uncovered some other issues that made the reconstruction much slower than it should have been (also resolved).

Additionally, we have made some benchmarks for optimizing the parameters for the 3D reconstruction, since it tended to be very poor in certain cases, and managed to significantly improve it:

Image of mesh quality with old and new parameters.
Mesh quality comparison with old parameters (left) and new parameters (right).

This also involved getting out of the Python comfort zone and implementing some infrastructure for C++ scripts using the CGAL library, which was fortunately rather straightforward. This will definitely prove useful in the future, since CGAL contains every mesh-editing tool one could ever wish for.


With the important things out of the way, we have one less important thing to share: a 3D-printable Climbuddy keychain which you can freely download as an STL and print in any two colors of your choice.

An image of the Climbuddy keychain.
An image of the Climbuddy keychain. Download available as [STL].
Can improve your climbing by up to 20%!

Team Climbuddy