Re: [gnugo-devel] linear_eye_space() considered harmful

[Gunnar Farneback]

Inge wrote:
> Is the function linear_eye_space still needed?  It is a very complex
> function and the same functionality could easily be created with a few
> methods in eyes.db.  Or perhaps, the necessary patterns are already
> there?

Not easily. The special case of topological false eyes coinciding with
opponent stones inside the eyespace doesn't have support in eyes.db
yet.

Dan wrote:
> It is still used. I am very skeptical that we have all the
> patterns implied by this function. But one way to try is
> to take it out and run the regressions. I expect some
> errors will pop up.

The test cases optics:312,325 in particular, which have the feature I
described above. It's possible that some other patterns handled by
linear_eye_space() are also missing, but there's a reasonable chance
that the heuristics for guessing nonmatched eyespace values will get
those right.

Btw, those heuristics are complex enough that they should be broken
out of compute_eyes_pessimistic() and be put in a function of their
own.

/Gunnar