In Brain in the Box I worked on their first Steam game Voodoo as a programmer. Voodoo is a multiplayer open-world survival game set amidst the fantasy wildlife of primal Africa. Champion the call of your tribe by hunting, gathering and crafting resources, building your village, and battling for territory and domination at the dawn of civilization.
One of the big challenges I faced in this project was the climbing system: it needed to be reliable, syncronized in multiplayer, function on a vast variety of models and on models that where moved by animators.
To do all that I choose to save where the vertices lead to if you follow a specific direction for example "what vertex do I find myself on if I follow this other vertex up direction?".
This kind of mapping of the mesh model was done in unity editor with a custom tool I wrote for the purpose: first automatically, then manually in the spots where the automatic map failed to find the correct vertex.
All this relationships between vertices where then saved in a file, ready to be loaded during game time when the mesh is instantiated in the scene.
Using this map the player can climb the mesh without encountering any problems if it moves in space.