Extending to different camera models

[Trzyq0712]

I was trying to extend ORB_SLAM3 to use a different camera model - Omni. However, I have faced a few issues while trying to implement.

• It is not really explained what some of the functions should do. Especially the following functions: epipolarConstrain, mathAndtriangulate, reconstructWithTwoViews.
• When I guessed what they should do, or just hardcoded them to return true or false, the examples I had would not really run (monocular) - they would start but pretty much fail to do any matches between frames.
• When I plugged the Omni model params into KannalaBrandt model, it wouldn't be accuarate but at least it would find matches.
• I then snooped around the code more and found references to the specific camera models (Pinhole, KannalaBrandt). This makes the code not really modular as the rest of the code stores enums of the camera type, or refers directly to a specific type (src/Frame.cc, src/Setting.cc, src/Tracking.cc, src/Atlas.cc). I now need to understand what the code does in those places (very hard as there is barely any documentation) in order to make my camera model work.

Help would be greatly appreciated.