* first few functions
* two more almost matching functions
* Rebase to NBS, get it to compile
* BgCheck_RaycastFloorStaticList OK, fix-up some functions
* BgCheck_SphVsStaticWall OK! and a few others
* more z_bgcheck NON_MATCHINGS
* OK more functions, reorganize external reference #defines
* More functions OK, more struct fixes
* More OKs
* Decomp all the way to the end of bgcheck
* All functions attempted
* Rename functions
* formatting, data migration
* Give names to unk structs, rename some structs, fix some non-equivalent functions
* WaterBox_GetSurfaceImpl OK
* BgCheck_ResetPolyCheckTbl OK, improve WaterBox_GetSurface2 codegen, eliminate warnings and clean up source.
* BcCheck3_BgActorInit ->BgCheck3_BgActorInit, fix warnings
* pr change requests
* fix crc maybe
* implement more changes
* implement alf's changes