Adds advanced_bullet_dodge_chance, for admin / mob use. Applies it to space combat drones (#25336)

* Adds advanced_bullet_dodge_chance, for admin / mob use

* actually just make it 25

* Apply suggestions from code review

Co-authored-by: 1080pCat <96908085+1080pCat@users.noreply.github.com>
Signed-off-by: Qwertytoforty <52090703+Qwertytoforty@users.noreply.github.com>

---------

Signed-off-by: Qwertytoforty <52090703+Qwertytoforty@users.noreply.github.com>
Co-authored-by: 1080pCat <96908085+1080pCat@users.noreply.github.com>

code/modules/mob/living/living.dm

@@ -6,6 +6,8 @@
 	faction += "\ref[src]"
 	determine_move_and_pull_forces()
 	GLOB.mob_living_list += src
+	if(advanced_bullet_dodge_chance)
+		RegisterSignal(src, COMSIG_ATOM_PREHIT, PROC_REF(advanced_bullet_dodge))
 
 // Used to determine the forces dependend on the mob size
 // Will only change the force if the force was not set in the mob type itself
@@ -51,6 +53,7 @@
 	QDEL_NULL(middleClickOverride)
 	if(mind?.current == src)
 		mind.current = null
+	UnregisterSignal(src, COMSIG_ATOM_PREHIT)
 	return ..()
 
 /mob/living/ghostize(can_reenter_corpse = 1)
@@ -1071,6 +1074,9 @@
 			update_transform()
 		if("lighting_alpha")
 			sync_lighting_plane_alpha()
+		if("advanced_bullet_dodge_chance")
+			UnregisterSignal(src, COMSIG_ATOM_PREHIT)
+			RegisterSignal(src, COMSIG_ATOM_PREHIT, PROC_REF(advanced_bullet_dodge))
 
 /mob/living/throw_at(atom/target, range, speed, mob/thrower, spin, diagonals_first, datum/callback/callback, force, dodgeable, block_movement)
 	stop_pulling()

code/modules/mob/living/living_defense.dm

@@ -51,6 +51,33 @@
 			check_projectile_dismemberment(P, def_zone)
 	return P.on_hit(src, armor, def_zone)
 
+/// Tries to dodge incoming bullets if we aren't disabled for any reasons. Advised to overide with advanced effects, this is as basic example admins can apply.
+/mob/living/proc/advanced_bullet_dodge(mob/living/source, obj/item/projectile/hitting_projectile)
+	SIGNAL_HANDLER
+
+	if(HAS_TRAIT(source, TRAIT_IMMOBILIZED))
+		return NONE
+	if(source.stat != CONSCIOUS)
+		return NONE
+	if(!prob(advanced_bullet_dodge_chance))
+		return NONE
+
+	source.visible_message(
+		"<span class='danger'>[source] [pick("dodges","jumps out of the way of","evades","dives out of the way of")] [hitting_projectile]!</span>",
+		"<span class='userdanger'>You evade [hitting_projectile]!</span>",
+	)
+	playsound(source, pick('sound/weapons/bulletflyby.ogg', 'sound/weapons/bulletflyby2.ogg', 'sound/weapons/bulletflyby3.ogg'), 75, TRUE)
+	var/dir_to_avoid = angle2dir_cardinal(hitting_projectile.Angle)
+	var/list/potential_first_directions = list(NORTH, SOUTH, EAST, WEST)
+	potential_first_directions -= dir_to_avoid
+	step(source, pick(potential_first_directions))
+	// Chance to dodge multiple shotgun spreads, but not likely. Mainly: Infinite loop prevention from admins setting it to 100 and doing something stupid.
+	// If you want to set your dodge chance to 100 on a subtype, no issue: Just make sure the subtype does not step in a direction, otherwise you'll have the mob move a large distance to dodge rubbershot.
+	if(prob(50))
+		addtimer(VARSET_CALLBACK(src, advanced_bullet_dodge_chance, advanced_bullet_dodge_chance), 0.25 SECONDS) // Returns fast enough for multiple laser shots.
+		advanced_bullet_dodge_chance = 0
+	return ATOM_PREHIT_FAILURE
+
 /mob/living/proc/check_projectile_dismemberment(obj/item/projectile/P, def_zone)
 	return 0
 

code/modules/mob/living/living_defines.dm

@@ -100,6 +100,9 @@
 	/// Famous last words -- if succumbing, what the user's last words were
 	var/last_words
 
+	///This variable is the chance for a mob to automatically dodge a bullet. Useful for admins, and applied to some mobs by default, such as the malfunctioning drone mobs.
+	var/advanced_bullet_dodge_chance = 0
+
 	/*
 	Taste Vars
 	*/

code/modules/mob/living/simple_animal/hostile/retaliate/combat_drone.dm

@@ -30,6 +30,7 @@
 	faction = list("malf_drone")
 	deathmessage = "suddenly breaks apart."
 	del_on_death = TRUE
+	advanced_bullet_dodge_chance = 25 // This will be adjusted when active, vs deactivated. Randomises on hit if it is zero.
 	var/passive_mode = TRUE // if true, don't target anything.
 
 /mob/living/simple_animal/hostile/malf_drone/Initialize(mapload)
@@ -69,6 +70,8 @@
 	do_sparks(3, 1, src)
 	passive_mode = FALSE
 	update_icons()
+	if(!advanced_bullet_dodge_chance)
+		advanced_bullet_dodge_chance = 25
 	. = ..() // this will handle finding a target if there is a valid one nearby
 
 /mob/living/simple_animal/hostile/malf_drone/Life(seconds, times_fired)
@@ -83,12 +86,38 @@
 		passive_mode = !passive_mode
 		if(passive_mode)
 			visible_message("<span class='notice'>[src] retracts several targetting vanes.</span>")
+			advanced_bullet_dodge_chance = 0
 			if(target)
 				LoseTarget()
 		else
 			visible_message("<span class='warning'>[src] suddenly lights up, and additional targetting vanes slide into place.</span>")
+			advanced_bullet_dodge_chance = 25
 		update_icons()
 
+/// We overide the basic effect, as malfunctioning drones are in space, and use jets to dodge. Also lets us do cool effects.
+/mob/living/simple_animal/hostile/malf_drone/advanced_bullet_dodge(mob/living/source, obj/item/projectile/hitting_projectile)
+	if(HAS_TRAIT(source, TRAIT_IMMOBILIZED))
+		return NONE
+	if(source.stat != CONSCIOUS)
+		return NONE
+	if(!prob(advanced_bullet_dodge_chance))
+		return NONE
+
+	source.visible_message(
+		"<span class='danger'>[source]'s jets [pick("boosts", "propels", "pulses", "flares up and moves", "shudders and pushes")] it out of '[hitting_projectile]'s way!</span>",
+		"<span class='userdanger'>You evade [hitting_projectile]!</span>",
+	)
+	playsound(source, pick('sound/weapons/bulletflyby.ogg', 'sound/weapons/bulletflyby2.ogg', 'sound/weapons/bulletflyby3.ogg', 'sound/effects/refill.ogg'), 75, TRUE)
+	var/dir_to_avoid = angle2dir_cardinal(hitting_projectile.Angle)
+	var/list/potential_first_directions = list(NORTH, SOUTH, EAST, WEST)
+	potential_first_directions -= dir_to_avoid
+	new /obj/effect/temp_visual/decoy/fading(source.loc, source)
+	step(source, pick(potential_first_directions))
+	if(prob(50))
+		addtimer(VARSET_CALLBACK(source, advanced_bullet_dodge_chance, advanced_bullet_dodge_chance), 0.25 SECONDS)
+		advanced_bullet_dodge_chance = 0
+	return ATOM_PREHIT_FAILURE
+
 /mob/living/simple_animal/hostile/malf_drone/emp_act(severity)
 	adjustHealth(100 / severity) // takes the same damage as a mining drone from emp