Improve performance of trace rays

[szapp]

Trace rays for focus and distance/obstacle collection are fired continuously every frame. Benchmarking showed that the freeAimRay function takes (worst-case) 100+ ms on a weak machine. Doing this each frame is a crime on performance.
The approach to return the previous results from the trace ray/focus collection every nth frame, instead of recalculating it every frame, failed, because Gothic's internal focus collection does not happen every frame either causing a discrepancy: Trace ray recalculation and internal focus update do no coincide, such that a new focus can never be captured by the trace ray (as it will be overwritten by the previous frames' results).
Task:
Either (1) find where Gothic's internal focus collection happens exactly, and hook at that address directly, or (2) force recalculation when the focus has changed.

[szapp]

If implementing (1) which should be most performance friendly, define the trace ray results as global variables, to make them accessible from different functions without the need to call the function.
Approach:

1. Hook void __thiscall oCNpc::CollectFocusVob(int) 0x733A10 and other candidates and print to zSpy every time the function is called, while also printing to zSpy from freeAimRay when Gothic updated the focus. This will help in finding the function which is really responsible for collecting the focus without much reading the engine functions themselves.
2. Once the focus collection function is identified, try to find a suitable address within to overwrite the collected focus. Test the validity of the function and the hook by overwriting the focus with zero to check if it stays zero (otherwise there is another function setting the focus vob).
3. Call a modified version of freeAimRay from that hooked address, where the results are stored in global variables, which can be accessed from anywhere any point in time.

[szapp]

Investigation of engine functions:
void __thiscall oCAIHuman::CheckFocusVob(int) 0x69B7A0 is called every frame (even in the menu, but not during animations like weapon switching). If there is no focus, it calls void __thiscall oCNpc::CollectFocusVob(int) 0x733A10. If there is a focus, however, it will stay the focus until it dies or the angles become to big(?).

[szapp]

The approach (1) did give some insights, but was not the way to go because it wouldn't resolve the problem of performance. The real issue turned out to be the function freeAimAnimation which was hooking the engine function int __thiscall oCAniCtrl_Human::InterpolateCombineAni(float float int) 0x6B6170 awkwardly, having freeAimAnimation called multiple times per frame.
The engine function is used for other purposes as well. The solution is to instead hook int __thiscall oCAIHuman::BowMode(int) 0x695F00 at the correct address (0x696296) where oCAniCtrl_Human::InterpolateCombineAni is called.