Collision detection

Selection in Unity is made possible using “colliders” that are placed in each point that detects collision with the selection tool. The native implementation in Unity is inefficient and would cause lag for more than 30k cells. To overcome this, a new collision detection system using Octrees (Meagher, 1982) and raycasts was engineered. The visual form of the octree is used in sub-graphing to show a skeleton of the data (as seen in Figure 3D) This is described at https://www.cellexalvr.med.lu.se/programmers-guide along with a detailed overview of the code structure and how to navigate it.