Fix is_critical checks

[burner1024]

is_critical is used in stat checks sometimes, that doesn't work.
Need to check the code for this and replace with custom implementation.

[burner1024]

It's actually worse: according to @NovaRain's research, is_critical in skill checks takes into account PC critical chance for calculating when to upgrade a success to a critical success.
And critical chance is affected by perks/traits such as More Criticals. Which means combat perks affect non-combat mechanics, which I consider another bug.
Maybe it should be fixed in sfall, or maybe the scripts can be switched to script-only critical implementation. Anyway, for now it's just a note to keep in mind.

[NovaRain]

is_critical in skill checks takes into account PC critical chance for calculating when to upgrade a success to a critical success.

It's roll_vs_skill script function takes PC critical chance into account when determining whether a success roll can be upgraded to a critical success.
https://github.com/alexbatalov/fallout2-re/blob/main/src/int/support/intextra.c#L689
https://github.com/alexbatalov/fallout2-re/blob/main/src/game/skill.c#L424
https://github.com/alexbatalov/fallout2-re/blob/main/src/game/roll.c#L67
https://github.com/alexbatalov/fallout2-re/blob/main/src/game/roll.c#L83

[burner1024]

Right, I misspoke. is_critical just checks the roll, mods are applied in actual roll.

[burner1024]

I think I was wrong in my second comment, trait modifiers seem to be applied separately.
And it does look like crit chance only counts on success roll. I guess... it's acceptable.

[burner1024]

As far as I understand, ROLL enums are sequential integer values in engine, so it should be enough to replace just the one stat roll function.

[burner1024]

I think I half-assed this.

Fallout2_Unofficial_Patch/scripts_src/headers/command.h

Line 492 in 4e3d2dc

variable stat_check = do_check(who, stat, mod);

should be is_success(do_check)

Fallout2_Unofficial_Patch/scripts_src/template/spear_trap.ssl

Lines 207 to 211 in 4e3d2dc

	Perception_Roll:=do_check(dude_obj,STAT_pe,PERCEPTION_BONUS);
	set_local_var(LVAR_Extended_Look,Perception_Roll);
	end
	if (is_critical(local_var(LVAR_Extended_Look))) then begin

Here perception roll still uses do_check. There are a few more cases like this.