MAX_VIEW_DISTANCE versus hardcoded 60

[mlangsdorf]

I’m looking to pick up https://github.com/CleverRaven/Cataclysm-DDA/pull/23376, with the eventual goal of making the size of the reality bubble into compile time option, or more preferably, something that can be selected from a list, either during world creation or during play.

game_constants.h defines MAX_VIEW_DISTANCE as ( SEEX * int( MAPSIZE / 2 ) ), which normally works out as 60. But lightmap.cpp and player.cpp hardcode max distance to 60.

Is that 60 in lightmap.cpp (cast_zlight and build_seen_cache) and player.cpp (unimpaired_range) really supposed to be MAX_VIEW_DISTANCE? If so, I’m guessing that directly adjusting MAX_VIEW_DISTANCE will break things. What breaks if I set MAPSIZE to 13?

[mlangsdorf]

So, replacing those instances of 60 with MAX_VIEW_DISTANCE, and then setting MAPSIZE to 15, sets the view distance to 84, as evidenced on the screen shot.

I need to adjust the air transparency - it’s currently set to go to dim at 60 tiles - but this looks like a very promising avenue of exploration.

[DeWolf]

sniper breathing intensifies

[kevin.granade]

The review comments in the pr are pretty trivial, the main thing that needs fixing is adding a formula to adjust air transparency as you noted.

[mlangsdorf]

I didn’t have time to experiment with this, but I think it’s not enough to change LIGHT_TRANSPARENCY_OPEN_AIR. Because LIGHT_RANGE depends on that value, which means the effective illumination of a given light will change.

I think all those values will need to be recalculated as the viewing distance changes. Not a huge deal, it’s just math.

Oh, and player::sight_range() should call LIGHT_RANGE instead of rederiving the formula.