Yogstation/code/modules/projectiles/projectile.dm

#define MOVES_HITSCAN -1		//Not actually hitscan but close as we get without actual hitscan.
#define MUZZLE_EFFECT_PIXEL_INCREMENT 17	//How many pixels to move the muzzle flash up so your character doesn't look like they're shitting out lasers.

/obj/item/projectile
	name = "projectile"
	icon = 'icons/obj/projectiles.dmi'
	icon_state = "bullet"
	density = FALSE
	anchored = TRUE
	item_flags = ABSTRACT
	pass_flags = PASSTABLE
	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
	movement_type = FLYING
	wound_bonus = CANT_WOUND // can't wound by default
	hitsound = 'sound/weapons/pierce.ogg'
	var/hitsound_wall = ""

	resistance_flags = LAVA_PROOF | FIRE_PROOF | UNACIDABLE | ACID_PROOF
	var/def_zone = ""	//Aiming at
	var/atom/movable/firer = null//Who shot it
	var/atom/fired_from = null // the atom that the projectile was fired from (gun, turret)
	var/suppressed = FALSE	//Attack message
	var/yo = null
	var/xo = null
	var/atom/original = null // the original target clicked
	var/turf/starting = null // the projectile's starting turf
	var/list/permutated = list() // we've passed through these atoms, don't try to hit them again
	var/p_x = 16
	var/p_y = 16			// the pixel location of the tile that the player clicked. Default is the center

	//Fired processing vars
	var/fired = FALSE	//Have we been fired yet
	var/paused = FALSE	//for suspending the projectile midair
	var/last_projectile_move = 0
	var/last_process = 0
	var/time_offset = 0
	var/datum/point/vector/trajectory
	var/trajectory_ignore_forcemove = FALSE	//instructs forceMove to NOT reset our trajectory to the new location!

	var/speed = 0.8			//Amount of deciseconds it takes for projectile to travel
	var/Angle = 0
	var/original_angle = 0		//Angle at firing
	var/nondirectional_sprite = FALSE //Set TRUE to prevent projectiles from having their sprites rotated based on firing angle
	var/spread = 0			//amount (in degrees) of projectile spread
	animate_movement = 0	//Use SLIDE_STEPS in conjunction with legacy
	var/ricochets = 0
	var/ricochets_max = 2
	var/ricochet_chance = 30
	var/force_hit = FALSE //If the object being hit can pass ths damage on to something else, it should not do it for this bullet.

	//Atom penetration, set to mobs by default
	var/penetrating = FALSE
	var/penetrations = INFINITY
	var/penetration_type = 0 //Set to 1 if you only want to have it penetrate objects. Set to 2 if you want it to penetrate objects and mobs.

	//Hitscan
	var/hitscan = FALSE		//Whether this is hitscan. If it is, speed is basically ignored.
	var/list/beam_segments	//assoc list of datum/point or datum/point/vector, start = end. Used for hitscan effect generation.
	var/datum/point/beam_index
	var/turf/hitscan_last	//last turf touched during hitscanning.
	var/tracer_type
	var/muzzle_type
	var/impact_type

	//Fancy hitscan lighting effects!
	var/hitscan_light_intensity = 1.5
	var/hitscan_light_range = 0.75
	var/hitscan_light_color_override
	var/muzzle_flash_intensity = 3
	var/muzzle_flash_range = 1.5
	var/muzzle_flash_color_override
	var/impact_light_intensity = 3
	var/impact_light_range = 2
	var/impact_light_color_override

	//Homing
	var/homing = FALSE
	var/atom/homing_target
	var/homing_turn_speed = 10		//Angle per tick.
	var/homing_inaccuracy_min = 0		//in pixels for these. offsets are set once when setting target.
	var/homing_inaccuracy_max = 0
	var/homing_offset_x = 0
	var/homing_offset_y = 0

	var/ignore_source_check = FALSE

	var/damage = 10
	var/damage_type = BRUTE //BRUTE, BURN, TOX, OXY, CLONE are the only things that should be in here
	var/nodamage = FALSE //Determines if the projectile will skip any damage inflictions
	var/flag = "bullet" //Defines what armor to use when it hits things.  Must be set to bullet, laser, energy,or bomb
	var/projectile_type = /obj/item/projectile
	var/range = 50 //This will de-increment every step. When 0, it will deletze the projectile.
	var/decayedRange			//stores original range
	var/reflect_range_decrease = 5			//amount of original range that falls off when reflecting, so it doesn't go forever
	var/reflectable = NONE // Can it be reflected or not?
		//Effects
	var/stun = 0
	var/knockdown = 0
	var/paralyze = 0
	var/immobilize = 0
	var/unconscious = 0
	var/irradiate = 0
	var/stutter = 0
	var/slur = 0
	var/eyeblur = 0
	var/drowsy = 0
	var/stamina = 0
	var/jitter = 0
	var/dismemberment = 0 //The higher the number, the greater the bonus to dismembering. 0 will not dismember at all.
	var/impact_effect_type //what type of impact effect to show when hitting something
	var/log_override = FALSE //is this type spammed enough to not log? (KAs)

	var/temporary_unstoppable_movement = FALSE

	///How much we want to drop both wound_bonus and bare_wound_bonus (to a minimum of 0 for the latter) per tile, for falloff purposes
	var/wound_falloff_tile

/obj/item/projectile/Initialize()
	. = ..()
	permutated = list()
	decayedRange = range

/obj/item/projectile/proc/Range()
	range--
	if(wound_bonus != CANT_WOUND)
		wound_bonus += wound_falloff_tile
		bare_wound_bonus = max(0, bare_wound_bonus + wound_falloff_tile)
	if(range <= 0 && loc)
		on_range()

/obj/item/projectile/proc/on_range() //if we want there to be effects when they reach the end of their range
	qdel(src)

//to get the correct limb (if any) for the projectile hit message
/mob/living/proc/check_limb_hit(hit_zone)
	if(has_limbs)
		return hit_zone

/mob/living/carbon/check_limb_hit(hit_zone)
	if(get_bodypart(hit_zone))
		return hit_zone
	else //when a limb is missing the damage is actually passed to the chest
		return BODY_ZONE_CHEST

/obj/item/projectile/proc/prehit(atom/target)
	return TRUE

/obj/item/projectile/proc/on_hit(atom/target, blocked = FALSE)
	if(fired_from)
		SEND_SIGNAL(fired_from, COMSIG_PROJECTILE_ON_HIT, firer, target, Angle)
	var/turf/target_loca = get_turf(target)

	var/hitx
	var/hity
	if(target == original)
		hitx = target.pixel_x + p_x - 16
		hity = target.pixel_y + p_y - 16
	else
		hitx = target.pixel_x + rand(-8, 8)
		hity = target.pixel_y + rand(-8, 8)

	if(!nodamage && (damage_type == BRUTE || damage_type == BURN) && iswallturf(target_loca) && prob(75))
		var/turf/closed/wall/W = target_loca
		if(impact_effect_type && !hitscan)
			new impact_effect_type(target_loca, hitx, hity)

		W.add_dent(WALL_DENT_SHOT, hitx, hity)

		if(penetrating && (penetration_type == 1 || penetration_type == 2) && penetrations > 0)
			penetrations -= 1
			return BULLET_ACT_FORCE_PIERCE

		return BULLET_ACT_HIT

	if(!isliving(target))
		if(impact_effect_type && !hitscan)
			new impact_effect_type(target_loca, hitx, hity)

		if(penetrating && (penetration_type == 1 || penetration_type == 2) && penetrations > 0)
			penetrations -= 1
			return BULLET_ACT_FORCE_PIERCE

		return BULLET_ACT_HIT

	var/mob/living/L = target

	if(blocked != 100) // not completely blocked
		if(damage && L.blood_volume && damage_type == BRUTE)
			var/mob/living/carbon/C = L
			var/splatter_dir = dir
			if(starting)
				splatter_dir = get_dir(starting, target_loca)
			if(isalien(L) || ispolysmorph(L))
				new /obj/effect/temp_visual/dir_setting/bloodsplatter/xenosplatter(target_loca, splatter_dir)
			else if (iscarbon(L) && !(NOBLOOD in C.dna.species.species_traits))
				new /obj/effect/temp_visual/dir_setting/bloodsplatter(target_loca, splatter_dir)
			else
				new /obj/effect/temp_visual/dir_setting/bloodsplatter/genericsplatter(target_loca, splatter_dir)
			var/obj/item/bodypart/B = L.get_bodypart(def_zone)
			if(B.status == BODYPART_ROBOTIC) // So if you hit a robotic, it sparks instead of bloodspatters
				do_sparks(2, FALSE, target.loc)
				if(prob(25))
					new /obj/effect/decal/cleanable/oil(target_loca)
			if(prob(33))
				L.add_splatter_floor(target_loca)
		else if(impact_effect_type && !hitscan)
			new impact_effect_type(target_loca, hitx, hity)

		var/organ_hit_text = ""
		var/limb_hit = L.check_limb_hit(def_zone)//to get the correct message info.
		if(limb_hit)
			organ_hit_text = " in \the [parse_zone(limb_hit)]"
		if(suppressed)
			playsound(loc, hitsound, 5, 1, -1)
			to_chat(L, span_userdanger("You're shot by \a [src][organ_hit_text]!"))
		else
			if(hitsound)
				var/volume = vol_by_damage()
				playsound(loc, hitsound, volume, 1, -1)
			L.visible_message(span_danger("[L] is hit by \a [src][organ_hit_text]!"), \
					span_userdanger("[L] is hit by \a [src][organ_hit_text]!"), null, COMBAT_MESSAGE_RANGE)
		L.on_hit(src)
	var/viruslist = "" // yogs - adds viruslist variable
	var/reagent_note
	if(reagents && reagents.reagent_list)
		reagent_note = " REAGENTS:"
		for(var/datum/reagent/R in reagents.reagent_list)
			reagent_note += "[R.name] ([num2text(R.volume)])"
// yogs start - Checks blood for disease
			if(istype(R, /datum/reagent/blood))
				var/datum/reagent/blood/RR = R
				for(var/datum/disease/D in RR.data["viruses"])
					viruslist += " [D.name]"
					if(istype(D, /datum/disease/advance))
						var/datum/disease/advance/DD = D
						viruslist += " \[ symptoms: "
						for(var/datum/symptom/S in DD.symptoms)
							viruslist += "[S.name] "
						viruslist += "\]"


	if(viruslist)
		investigate_log("[firer] injected [src] using a projectile with [viruslist] [blocked == 100 ? "BLOCKED" : ""]", INVESTIGATE_VIROLOGY)
		log_game("[firer] injected [src] using a projectile with [viruslist] [blocked == 100 ? "BLOCKED" : ""]")
// yogs end

	if(ismob(firer))
		log_combat(firer, L, "shot", src, reagent_note)
	else
		L.log_message("has been shot by [firer] with [src]", LOG_ATTACK, color="orange")

	return L.apply_effects(stun, knockdown, unconscious, irradiate, slur, stutter, eyeblur, drowsy, blocked, stamina, jitter, paralyze, immobilize)

/obj/item/projectile/proc/vol_by_damage()
	if(src.damage)
		return clamp((src.damage) * 0.67, 30, 100)// Multiply projectile damage by 0.67, then CLAMP the value between 30 and 100
	else
		return 50 //if the projectile doesn't do damage, play its hitsound at 50% volume

/obj/item/projectile/proc/on_ricochet(atom/A)
	return

/obj/item/projectile/proc/store_hitscan_collision(datum/point/pcache)
	beam_segments[beam_index] = pcache
	beam_index = pcache
	beam_segments[beam_index] = null

/obj/item/projectile/Bump(atom/A)
	if(!trajectory)
		qdel(src)
		return
	var/datum/point/pcache = trajectory.copy_to()
	var/turf/T = get_turf(A)
	if(check_ricochet(A) && check_ricochet_flag(A) && ricochets < ricochets_max)
		ricochets++
		if(A.handle_ricochet(src))
			on_ricochet(A)
			ignore_source_check = TRUE
			decayedRange = max(0, decayedRange - reflect_range_decrease)
			range = decayedRange
			if(hitscan)
				store_hitscan_collision(pcache)
			return TRUE

	var/distance = get_dist(T, starting) // Get the distance between the turf shot from and the mob we hit and use that for the calculations.
	def_zone = ran_zone(def_zone, max(100-(7*distance), 5)) //Lower accurancy/longer range tradeoff. 7 is a balanced number to use.

	if(isturf(A) && hitsound_wall)
		var/volume = clamp(vol_by_damage() + 20, 0, 100)
		if(suppressed)
			volume = 5
		playsound(loc, hitsound_wall, volume, 1, -1)

	return process_hit(T, select_target(T, A))

#define QDEL_SELF 1			//Delete if we're not UNSTOPPABLE flagged non-temporarily
#define DO_NOT_QDEL 2		//Pass through.
#define FORCE_QDEL 3		//Force deletion.

/obj/item/projectile/proc/process_hit(turf/T, atom/target, qdel_self, hit_something = FALSE)		//probably needs to be reworked entirely when pixel movement is done.
	if(QDELETED(src) || !T || !target)		//We're done, nothing's left.
		if((qdel_self == FORCE_QDEL) || ((qdel_self == QDEL_SELF) && !temporary_unstoppable_movement && !CHECK_BITFIELD(movement_type, UNSTOPPABLE)))
			qdel(src)
		return hit_something
	permutated |= target		//Make sure we're never hitting it again. If we ever run into weirdness with piercing projectiles needing to hit something multiple times.. well.. that's a to-do.
	if(!prehit(target))
		return process_hit(T, select_target(T), qdel_self, hit_something)		//Hit whatever else we can since that didn't work.
	var/result = target.bullet_act(src, def_zone)
	if(result == BULLET_ACT_FORCE_PIERCE)
		if(!CHECK_BITFIELD(movement_type, UNSTOPPABLE))
			temporary_unstoppable_movement = TRUE
			ENABLE_BITFIELD(movement_type, UNSTOPPABLE)
		return process_hit(T, select_target(T), qdel_self, TRUE)		//Hit whatever else we can since we're piercing through but we're still on the same tile.
	else if(result == BULLET_ACT_PENETRATE) // This is slightly different from ACT_TURF in that it goes through the first thing
		return process_hit(T, select_target(T), qdel_self, TRUE)
	else if(result == BULLET_ACT_TURF)									//We hit the turf but instead we're going to also hit something else on it.
		return process_hit(T, select_target(T), QDEL_SELF, TRUE)
	else		//Whether it hit or blocked, we're done!
		qdel_self = QDEL_SELF
		hit_something = TRUE
	if((qdel_self == FORCE_QDEL) || ((qdel_self == QDEL_SELF) && !temporary_unstoppable_movement && !CHECK_BITFIELD(movement_type, UNSTOPPABLE)))
		qdel(src)
	return hit_something

#undef QDEL_SELF
#undef DO_NOT_QDEL
#undef FORCE_QDEL

/obj/item/projectile/proc/select_target(turf/T, atom/target)			//Select a target from a turf.
	if((original in T) && can_hit_target(original, permutated, TRUE, TRUE))
		return original
	if(target && can_hit_target(target, permutated, target == original, TRUE))
		return target
	var/list/mob/living/possible_mobs = typecache_filter_list(T, GLOB.typecache_mob)
	var/list/mob/mobs = list()
	for(var/mob/living/M in possible_mobs)
		if(!can_hit_target(M, permutated, M == original, TRUE))
			continue
		mobs += M
	var/mob/M = safepick(mobs)
	if(M)
		return M.lowest_buckled_mob()
	var/list/obj/possible_objs = typecache_filter_list(T, GLOB.typecache_machine_or_structure)
	var/list/obj/objs = list()
	for(var/obj/O in possible_objs)
		if(!can_hit_target(O, permutated, O == original, TRUE))
			continue
		objs += O
	var/obj/O = safepick(objs)
	if(O)
		return O
	//Nothing else is here that we can hit, hit the turf if we haven't.
	if(!(T in permutated) && can_hit_target(T, permutated, T == original, TRUE))
		return T
	//Returns null if nothing at all was found.

/obj/item/projectile/proc/check_ricochet()
	if(prob(ricochet_chance))
		return TRUE
	return FALSE

/obj/item/projectile/proc/check_ricochet_flag(atom/A)
	if(A.flags_1 & CHECK_RICOCHET_1)
		return TRUE
	return FALSE

/obj/item/projectile/proc/return_predicted_turf_after_moves(moves, forced_angle)		//I say predicted because there's no telling that the projectile won't change direction/location in flight.
	if(!trajectory && isnull(forced_angle) && isnull(Angle))
		return FALSE
	var/datum/point/vector/current = trajectory
	if(!current)
		var/turf/T = get_turf(src)
		current = new(T.x, T.y, T.z, pixel_x, pixel_y, isnull(forced_angle)? Angle : forced_angle, SSprojectiles.global_pixel_speed)
	var/datum/point/vector/v = current.return_vector_after_increments(moves * SSprojectiles.global_iterations_per_move)
	return v.return_turf()

/obj/item/projectile/proc/return_pathing_turfs_in_moves(moves, forced_angle)
	var/turf/current = get_turf(src)
	var/turf/ending = return_predicted_turf_after_moves(moves, forced_angle)
	return getline(current, ending)

/obj/item/projectile/Process_Spacemove(movement_dir = 0)
	return TRUE	//Bullets don't drift in space

/obj/item/projectile/process()
	last_process = world.time
	if(!loc || !fired || !trajectory)
		fired = FALSE
		return PROCESS_KILL
	if(paused || !isturf(loc))
		last_projectile_move += world.time - last_process		//Compensates for pausing, so it doesn't become a hitscan projectile when unpaused from charged up ticks.
		return
	var/elapsed_time_deciseconds = (world.time - last_projectile_move) + time_offset
	time_offset = 0
	var/required_moves = speed > 0? FLOOR(elapsed_time_deciseconds / speed, 1) : MOVES_HITSCAN			//Would be better if a 0 speed made hitscan but everyone hates those so I can't make it a universal system :<
	if(required_moves == MOVES_HITSCAN)
		required_moves = SSprojectiles.global_max_tick_moves
	else
		if(required_moves > SSprojectiles.global_max_tick_moves)
			var/overrun = required_moves - SSprojectiles.global_max_tick_moves
			required_moves = SSprojectiles.global_max_tick_moves
			time_offset += overrun * speed
		time_offset += MODULUS(elapsed_time_deciseconds, speed)

	for(var/i in 1 to required_moves)
		pixel_move(1, FALSE)

/obj/item/projectile/proc/fire(angle, atom/direct_target)
	if(fired_from)
		SEND_SIGNAL(fired_from, COMSIG_PROJECTILE_BEFORE_FIRE, src, original)
	//If no angle needs to resolve it from xo/yo!
	if(!log_override && firer && original)
		log_combat(firer, original, "fired at", src, "from [get_area_name(src, TRUE)]")
	if(direct_target)
		if(prehit(direct_target))
			direct_target.bullet_act(src, def_zone)
			qdel(src)
			return
	if(isnum(angle))
		setAngle(angle)
	if(spread)
		setAngle(Angle + ((rand() - 0.5) * spread))
	var/turf/starting = get_turf(src)
	if(isnull(Angle))	//Try to resolve through offsets if there's no angle set.
		if(isnull(xo) || isnull(yo))
			stack_trace("WARNING: Projectile [type] deleted due to being unable to resolve a target after angle was null!")
			qdel(src)
			return
		var/turf/target = locate(clamp(starting + xo, 1, world.maxx), clamp(starting + yo, 1, world.maxy), starting.z)
		setAngle(Get_Angle(src, target))
	original_angle = Angle
	if(!nondirectional_sprite)
		var/matrix/M = new
		M.Turn(Angle)
		transform = M
	trajectory_ignore_forcemove = TRUE
	forceMove(starting)
	trajectory_ignore_forcemove = FALSE
	trajectory = new(starting.x, starting.y, starting.z, pixel_x, pixel_y, Angle, SSprojectiles.global_pixel_speed)
	last_projectile_move = world.time
	fired = TRUE
	if(hitscan)
		process_hitscan()
	if(!(datum_flags & DF_ISPROCESSING))
		START_PROCESSING(SSprojectiles, src)
	pixel_move(1, FALSE)	//move it now!

/obj/item/projectile/proc/setAngle(new_angle)	//wrapper for overrides.
	Angle = new_angle
	if(!nondirectional_sprite)
		var/matrix/M = new
		M.Turn(Angle)
		transform = M
	if(trajectory)
		trajectory.set_angle(new_angle)
	return TRUE

/obj/item/projectile/forceMove(atom/target)
	if(!isloc(target) || !isloc(loc) || !z)
		return ..()
	var/zc = target.z != z
	var/old = loc
	if(zc)
		before_z_change(old, target)
	. = ..()
	if(trajectory && !trajectory_ignore_forcemove && isturf(target))
		if(hitscan)
			finalize_hitscan_and_generate_tracers(FALSE)
		trajectory.initialize_location(target.x, target.y, target.z, 0, 0)
		if(hitscan)
			record_hitscan_start(RETURN_PRECISE_POINT(src))
	if(zc)
		after_z_change(old, target)

/obj/item/projectile/proc/after_z_change(atom/olcloc, atom/newloc)

/obj/item/projectile/proc/before_z_change(atom/oldloc, atom/newloc)

/obj/item/projectile/vv_edit_var(var_name, var_value)
	switch(var_name)
		if(NAMEOF(src, Angle))
			setAngle(var_value)
			return TRUE
		else
			return ..()

/obj/item/projectile/proc/set_pixel_speed(new_speed)
	if(trajectory)
		trajectory.set_speed(new_speed)
		return TRUE
	return FALSE

/obj/item/projectile/proc/record_hitscan_start(datum/point/pcache)
	if(pcache)
		beam_segments = list()
		beam_index = pcache
		beam_segments[beam_index] = null	//record start.

/obj/item/projectile/proc/process_hitscan()
	var/safety = range * 3
	record_hitscan_start(RETURN_POINT_VECTOR_INCREMENT(src, Angle, MUZZLE_EFFECT_PIXEL_INCREMENT, 1))
	while(loc && !QDELETED(src))
		if(paused)
			stoplag(1)
			continue
		if(safety-- <= 0)
			if(loc)
				Bump(loc)
			if(!QDELETED(src))
				qdel(src)
			return	//Kill!
		pixel_move(1, TRUE)

/obj/item/projectile/proc/pixel_move(trajectory_multiplier, hitscanning = FALSE)
	if(!loc || !trajectory)
		return
	last_projectile_move = world.time
	if(!nondirectional_sprite && !hitscanning)
		var/matrix/M = new
		M.Turn(Angle)
		transform = M
	if(homing)
		process_homing()
	var/forcemoved = FALSE
	for(var/i in 1 to SSprojectiles.global_iterations_per_move)
		if(QDELETED(src))
			return
		trajectory.increment(trajectory_multiplier)
		var/turf/T = trajectory.return_turf()
		if(!istype(T))
			qdel(src)
			return
		if(T.z != loc.z)
			var/old = loc
			before_z_change(loc, T)
			trajectory_ignore_forcemove = TRUE
			forceMove(T)
			trajectory_ignore_forcemove = FALSE
			after_z_change(old, loc)
			if(!hitscanning)
				pixel_x = trajectory.return_px()
				pixel_y = trajectory.return_py()
			forcemoved = TRUE
			hitscan_last = loc
		else if(T != loc)
			step_towards(src, T)
			hitscan_last = loc
	if(!hitscanning && !forcemoved)
		pixel_x = trajectory.return_px() - trajectory.mpx * trajectory_multiplier * SSprojectiles.global_iterations_per_move
		pixel_y = trajectory.return_py() - trajectory.mpy * trajectory_multiplier * SSprojectiles.global_iterations_per_move
		animate(src, pixel_x = trajectory.return_px(), pixel_y = trajectory.return_py(), time = 0.1 SECONDS, flags = ANIMATION_END_NOW)
	Range()

/obj/item/projectile/proc/process_homing()			//may need speeding up in the future performance wise.
	if(!homing_target)
		return FALSE
	var/datum/point/PT = RETURN_PRECISE_POINT(homing_target)
	PT.x += clamp(homing_offset_x, 1, world.maxx)
	PT.y += clamp(homing_offset_y, 1, world.maxy)
	var/angle = closer_angle_difference(Angle, angle_between_points(RETURN_PRECISE_POINT(src), PT))
	setAngle(Angle + clamp(angle, -homing_turn_speed, homing_turn_speed))

/obj/item/projectile/proc/set_homing_target(atom/A)
	if(!A || (!isturf(A) && !isturf(A.loc)))
		return FALSE
	homing = TRUE
	homing_target = A
	homing_offset_x = rand(homing_inaccuracy_min, homing_inaccuracy_max)
	homing_offset_y = rand(homing_inaccuracy_min, homing_inaccuracy_max)
	if(prob(50))
		homing_offset_x = -homing_offset_x
	if(prob(50))
		homing_offset_y = -homing_offset_y

//Returns true if the target atom is on our current turf and above the right layer
//If direct target is true it's the originally clicked target.
/obj/item/projectile/proc/can_hit_target(atom/target, list/passthrough, direct_target = FALSE, ignore_loc = FALSE)
	if(QDELETED(target))
		return FALSE
	if(!ignore_source_check && firer)
		var/mob/M = firer
		if(isliving(M))
			var/mob/living/L = M
			if((target in L.hasparasites()) && target.loc == L.loc)
				return FALSE
		if((target == firer) || ((target == firer.loc) && (ismecha(firer.loc) || isspacepod(firer.loc))) || (target in firer.buckled_mobs) || (istype(M) && (M.buckled == target))) //cannot shoot yourself or your mech // yogs - or your spacepod)
			return FALSE
	if(!ignore_loc && (loc != target.loc))
		return FALSE
	if(target in passthrough)
		return FALSE
	if(target.density)		//This thing blocks projectiles, hit it regardless of layer/mob stuns/etc.
		return TRUE
	if(!isliving(target))
		if(target.layer < PROJECTILE_HIT_THRESHHOLD_LAYER)
			return FALSE
	else
		var/mob/living/L = target
		if(!direct_target)
			if(!CHECK_BITFIELD(L.mobility_flags, MOBILITY_STAND) && (L in range(2, starting))) //if we're shooting over someone who's prone and nearby bc formations are cool and not going to be unbalanced
				return FALSE
			if(!CHECK_BITFIELD(L.mobility_flags, MOBILITY_USE | MOBILITY_STAND | MOBILITY_MOVE) || !(L.stat == CONSCIOUS))		//If they're able to 1. stand or 2. use items or 3. move, AND they are not softcrit,  they are not stunned enough to dodge projectiles passing over.
				return FALSE
	return TRUE

//Spread is FORCED!
/obj/item/projectile/proc/preparePixelProjectile(atom/target, atom/source, params, spread = 0)
	var/turf/curloc = get_turf(source)
	var/turf/targloc = get_turf(target)
	trajectory_ignore_forcemove = TRUE
	forceMove(get_turf(source))
	trajectory_ignore_forcemove = FALSE
	starting = get_turf(source)
	original = target
	if(targloc || !params)
		yo = targloc.y - curloc.y
		xo = targloc.x - curloc.x
		setAngle(Get_Angle(src, targloc) + spread)

	if(isliving(source) && params)
		var/list/calculated = calculate_projectile_angle_and_pixel_offsets(source, params)
		p_x = calculated[2]
		p_y = calculated[3]

		setAngle(calculated[1] + spread)
	else if(targloc)
		yo = targloc.y - curloc.y
		xo = targloc.x - curloc.x
		setAngle(Get_Angle(src, targloc) + spread)
	else
		stack_trace("WARNING: Projectile [type] fired without either mouse parameters, or a target atom to aim at!")
		qdel(src)

/proc/calculate_projectile_angle_and_pixel_offsets(mob/user, params)
	var/list/mouse_control = params2list(params)
	var/p_x = 0
	var/p_y = 0
	var/angle = 0
	if(mouse_control["icon-x"])
		p_x = text2num(mouse_control["icon-x"])
	if(mouse_control["icon-y"])
		p_y = text2num(mouse_control["icon-y"])
	if(mouse_control["screen-loc"])
		//Split screen-loc up into X+Pixel_X and Y+Pixel_Y
		var/list/screen_loc_params = splittext(mouse_control["screen-loc"], ",")

		//Split X+Pixel_X up into list(X, Pixel_X)
		var/list/screen_loc_X = splittext(screen_loc_params[1],":")

		//Split Y+Pixel_Y up into list(Y, Pixel_Y)
		var/list/screen_loc_Y = splittext(screen_loc_params[2],":")
		var/x = text2num(screen_loc_X[1]) * 32 + text2num(screen_loc_X[2]) - 32
		var/y = text2num(screen_loc_Y[1]) * 32 + text2num(screen_loc_Y[2]) - 32

		//Calculate the "resolution" of screen based on client's view and world's icon size. This will work if the user can view more tiles than average.
		var/list/screenview = getviewsize(user.client.view)
		var/screenviewX = screenview[1] * world.icon_size
		var/screenviewY = screenview[2] * world.icon_size

		var/ox = round(screenviewX/2) - user.client.pixel_x //"origin" x
		var/oy = round(screenviewY/2) - user.client.pixel_y //"origin" y
		angle = ATAN2(y - oy, x - ox)
	return list(angle, p_x, p_y)

/obj/item/projectile/Crossed(atom/movable/AM) //A mob moving on a tile with a projectile is hit by it.
	. = ..()
	if(isliving(AM) && !(pass_flags & PASSMOB))
		var/mob/living/L = AM
		if(can_hit_target(L, permutated, (AM == original)))
			Bump(AM)

/obj/item/projectile/Move(atom/newloc, dir = NONE)
	. = ..()
	if(.)
		if(temporary_unstoppable_movement)
			temporary_unstoppable_movement = FALSE
			DISABLE_BITFIELD(movement_type, UNSTOPPABLE)
		if(fired && can_hit_target(original, permutated, TRUE))
			Bump(original)

/obj/item/projectile/Destroy()
	if(hitscan)
		finalize_hitscan_and_generate_tracers()
	STOP_PROCESSING(SSprojectiles, src)
	cleanup_beam_segments()
	qdel(trajectory)
	return ..()

/obj/item/projectile/proc/cleanup_beam_segments()
	QDEL_LIST_ASSOC(beam_segments)
	beam_segments = list()
	qdel(beam_index)

/obj/item/projectile/proc/finalize_hitscan_and_generate_tracers(impacting = TRUE)
	if(trajectory && beam_index)
		var/datum/point/pcache = trajectory.copy_to()
		beam_segments[beam_index] = pcache
	generate_hitscan_tracers(null, null, impacting)

/obj/item/projectile/proc/generate_hitscan_tracers(cleanup = TRUE, duration = 3, impacting = TRUE)
	if(!length(beam_segments))
		return
	if(tracer_type)
		var/tempref = REF(src)
		for(var/datum/point/p in beam_segments)
			generate_tracer_between_points(p, beam_segments[p], tracer_type, color, duration, hitscan_light_range, hitscan_light_color_override, hitscan_light_intensity, tempref)
	if(muzzle_type && duration > 0)
		var/datum/point/p = beam_segments[1]
		var/atom/movable/thing = new muzzle_type
		p.move_atom_to_src(thing)
		var/matrix/M = new
		M.Turn(original_angle)
		thing.transform = M
		thing.color = color
		thing.set_light(muzzle_flash_range, muzzle_flash_intensity, muzzle_flash_color_override? muzzle_flash_color_override : color)
		QDEL_IN(thing, duration)
	if(impacting && impact_type && duration > 0)
		var/datum/point/p = beam_segments[beam_segments[beam_segments.len]]
		var/atom/movable/thing = new impact_type
		p.move_atom_to_src(thing)
		var/matrix/M = new
		M.Turn(Angle)
		thing.transform = M
		thing.color = color
		thing.set_light(impact_light_range, impact_light_intensity, impact_light_color_override? impact_light_color_override : color)
		QDEL_IN(thing, duration)
	if(cleanup)
		cleanup_beam_segments()

/obj/item/projectile/experience_pressure_difference()
	return