Fixes reflection of hitscan beams against tiles (#56881)

Co-authored-by: Ranged <nickvanderkroon@gmail.com>

code/datums/martial/sleeping_carp.dm

@@ -113,7 +113,7 @@
 		A.visible_message("<span class='danger'>[A] effortlessly swats the projectile aside! They can block bullets with their bare hands!</span>", "<span class='userdanger'>You deflect the projectile!</span>")
 		playsound(get_turf(A), pick('sound/weapons/bulletflyby.ogg', 'sound/weapons/bulletflyby2.ogg', 'sound/weapons/bulletflyby3.ogg'), 75, TRUE)
 		P.firer = A
-		P.setAngle(rand(0, 360))//SHING
+		P.set_angle(rand(0, 360))//SHING
 		return BULLET_ACT_FORCE_PIERCE
 	return BULLET_ACT_HIT
 

code/datums/position_point_vector.dm

@@ -11,8 +11,8 @@
 
 /proc/point_midpoint_points(datum/point/a, datum/point/b) //Obviously will not support multiZ calculations! Same for the two below.
 	var/datum/point/P = new
-	P.x = a.x + (b.x - a.x) / 2
-	P.y = a.y + (b.y - a.y) / 2
+	P.x = a.x + (b.x - a.x) * 0.5
+	P.y = a.y + (b.y - a.y) * 0.5
 	P.z = a.z
 	return P
 
@@ -22,7 +22,8 @@
 /proc/angle_between_points(datum/point/a, datum/point/b)
 	return ATAN2((b.y - a.y), (b.x - a.x))
 
-/datum/position //For positions with map x/y/z and pixel x/y so you don't have to return lists. Could use addition/subtraction in the future I guess.
+/// For positions with map x/y/z and pixel x/y so you don't have to return lists. Could use addition/subtraction in the future I guess.
+/datum/position	
 	var/x = 0
 	var/y = 0
 	var/z = 0
@@ -66,7 +67,8 @@
 /datum/position/proc/return_point()
 	return new /datum/point(src)
 
-/datum/point //A precise point on the map in absolute pixel locations based on world.icon_size. Pixels are FROM THE EDGE OF THE MAP!
+/// A precise point on the map in absolute pixel locations based on world.icon_size. Pixels are FROM THE EDGE OF THE MAP!
+/datum/point		
 	var/x = 0
 	var/y = 0
 	var/z = 0
@@ -80,7 +82,8 @@
 	p.z = z
 	return p
 
-/datum/point/New(_x, _y, _z, _pixel_x = 0, _pixel_y = 0) //first argument can also be a /datum/position or /atom.
+/// First argument can also be a /datum/position or /atom.
+/datum/point/New(_x, _y, _z, _pixel_x = 0, _pixel_y = 0)	
 	if(istype(_x, /datum/position))
 		var/datum/position/P = _x
 		_x = P.x
@@ -99,9 +102,9 @@
 
 /datum/point/proc/initialize_location(tile_x, tile_y, tile_z, p_x = 0, p_y = 0)
 	if(!isnull(tile_x))
-		x = ((tile_x - 1) * world.icon_size) + world.icon_size / 2 + p_x + 1
+		x = ((tile_x - 1) * world.icon_size) + world.icon_size * 0.5 + p_x + 1
 	if(!isnull(tile_y))
-		y = ((tile_y - 1) * world.icon_size) + world.icon_size / 2 + p_y + 1
+		y = ((tile_y - 1) * world.icon_size) + world.icon_size * 0.5 + p_y + 1
 	if(!isnull(tile_z))
 		z = tile_z
 
@@ -130,10 +133,13 @@
 	return MODULUS(y, world.icon_size) - 16 - 1
 
 /datum/point/vector
-	var/speed = 32 //pixels per iteration
+	/// Pixels per iteration
+	var/speed = 32				
 	var/iteration = 0
 	var/angle = 0
-	var/mpx = 0 //calculated x/y movement amounts to prevent having to do trig every step.
+	/// Calculated x movement amounts to prevent having to do trig every step.
+	var/mpx = 0					
+	/// Calculated y movement amounts to prevent having to do trig every step.
 	var/mpy = 0
 	var/starting_x = 0 //just like before, pixels from EDGE of map! This is set in initialize_location().
 	var/starting_y = 0
@@ -151,6 +157,15 @@
 	starting_y = y
 	starting_z = z
 
+/// Same effect as initiliaze_location, but without setting the starting_x/y/z
+/datum/point/vector/proc/set_location(tile_x, tile_y, tile_z, p_x = 0, p_y = 0) 
+	if(!isnull(tile_x))
+		x = ((tile_x - 1) * world.icon_size) + world.icon_size * 0.5 + p_x + 1
+	if(!isnull(tile_y))
+		y = ((tile_y - 1) * world.icon_size) + world.icon_size * 0.5 + p_y + 1
+	if(!isnull(tile_z))
+		z = tile_z
+
 /datum/point/vector/copy_to(datum/point/vector/v = new)
 	..(v)
 	v.speed = speed
@@ -168,7 +183,8 @@
 		speed = pixel_speed
 	set_angle(new_angle)
 
-/datum/point/vector/proc/set_angle(new_angle) //calculations use "byond angle" where north is 0 instead of 90, and south is 180 instead of 270.
+/// Calculations use "byond angle" where north is 0 instead of 90, and south is 180 instead of 270.
+/datum/point/vector/proc/set_angle(new_angle)
 	if(isnull(angle))
 		return
 	angle = new_angle

code/game/atoms.dm

@@ -303,7 +303,7 @@
 		if((a_incidence_s < 90 && a_incidence_s < 90 - P.ricochet_incidence_leeway) || (a_incidence_s > 270 && a_incidence_s -270 > P.ricochet_incidence_leeway))
 			return FALSE
 	var/new_angle_s = SIMPLIFY_DEGREES(face_angle + incidence_s)
-	P.setAngle(new_angle_s)
+	P.set_angle(new_angle_s)
 	return TRUE
 
 ///Can the mover object pass this atom, while heading for the target turf

code/game/objects/structures/reflector.dm

@@ -26,9 +26,9 @@
 		add_overlay(deflector_overlay)
 
 	if(rotation_angle == -1)
-		setAngle(dir2angle(dir))
+		set_angle(dir2angle(dir))
 	else
-		setAngle(rotation_angle)
+		set_angle(rotation_angle)
 
 	if(admin)
 		can_rotate = FALSE
@@ -43,7 +43,7 @@
 			else
 				. += "<span class='notice'>Use screwdriver to unlock the rotation.</span>"
 
-/obj/structure/reflector/proc/setAngle(new_angle)
+/obj/structure/reflector/proc/set_angle(new_angle)
 	if(can_rotate)
 		rotation_angle = new_angle
 		if(deflector_overlay)
@@ -160,7 +160,7 @@
 	if(!user.canUseTopic(src, BE_CLOSE, NO_DEXTERITY, FALSE, !iscyborg(user)))
 		return
 	if(!isnull(new_angle))
-		setAngle(SIMPLIFY_DEGREES(new_angle))
+		set_angle(SIMPLIFY_DEGREES(new_angle))
 	return TRUE
 
 /obj/structure/reflector/AltClick(mob/user)
@@ -195,7 +195,7 @@
 	if(abs(incidence) > 90 && abs(incidence) < 270)
 		return FALSE
 	var/new_angle = SIMPLIFY_DEGREES(rotation_angle + incidence)
-	P.setAngle(new_angle)
+	P.set_angle_centered(new_angle)
 	return ..()
 
 //DOUBLE
@@ -219,7 +219,7 @@
 /obj/structure/reflector/double/auto_reflect(obj/projectile/P, pdir, turf/ploc, pangle)
 	var/incidence = GET_ANGLE_OF_INCIDENCE(rotation_angle, (P.Angle + 180))
 	var/new_angle = SIMPLIFY_DEGREES(rotation_angle + incidence)
-	P.setAngle(new_angle)
+	P.set_angle_centered(new_angle)
 	return ..()
 
 //BOX
@@ -241,7 +241,7 @@
 	anchored = TRUE
 
 /obj/structure/reflector/box/auto_reflect(obj/projectile/P)
-	P.setAngle(rotation_angle)
+	P.set_angle_centered(rotation_angle)
 	return ..()
 
 /obj/structure/reflector/ex_act()

code/modules/mob/living/carbon/human/human_defense.dm

@@ -90,7 +90,7 @@
 					var/new_angle_s = P.Angle + rand(120,240)
 					while(new_angle_s > 180) // Translate to regular projectile degrees
 						new_angle_s -= 360
-					P.setAngle(new_angle_s)
+					P.set_angle(new_angle_s)
 
 				return BULLET_ACT_FORCE_PIERCE // complete projectile permutation
 

code/modules/mob/living/simple_animal/constructs.dm

@@ -170,7 +170,7 @@
 				var/new_angle_s = P.Angle + rand(120,240)
 				while(new_angle_s > 180) // Translate to regular projectile degrees
 					new_angle_s -= 360
-				P.setAngle(new_angle_s)
+				P.set_angle(new_angle_s)
 
 			return BULLET_ACT_FORCE_PIERCE // complete projectile permutation
 

code/modules/projectiles/projectile.dm

@@ -317,11 +317,11 @@
 			unlucky_sob = L
 
 	if(unlucky_sob)
-		setAngle(Get_Angle(src, unlucky_sob.loc))
+		set_angle(Get_Angle(src, unlucky_sob.loc))
 
-/obj/projectile/proc/store_hitscan_collision(datum/point/pcache)
-	beam_segments[beam_index] = pcache
-	beam_index = pcache
+/obj/projectile/proc/store_hitscan_collision(datum/point/point_cache)
+	beam_segments[beam_index] = point_cache
+	beam_index = point_cache
 	beam_segments[beam_index] = null
 
 /obj/projectile/Bump(atom/A)
@@ -347,7 +347,7 @@
 		return FALSE
 	if(impacted[A]) // NEVER doublehit
 		return FALSE
-	var/datum/point/pcache = trajectory.copy_to()
+	var/datum/point/point_cache = trajectory.copy_to()
 	var/turf/T = get_turf(A)
 	if(ricochets < ricochets_max && check_ricochet_flag(A) && check_ricochet(A))
 		ricochets++
@@ -360,7 +360,7 @@
 			damage *= ricochet_decay_damage
 			range = decayedRange
 			if(hitscan)
-				store_hitscan_collision(pcache)
+				store_hitscan_collision(point_cache)
 			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.
@@ -663,9 +663,9 @@
 		if(QDELETED(src))
 			return
 	if(isnum(angle))
-		setAngle(angle)
+		set_angle(angle)
 	if(spread)
-		setAngle(Angle + ((rand() - 0.5) * spread))
+		set_angle(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))
@@ -673,12 +673,12 @@
 			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))
+		set_angle(Get_Angle(src, target))
 	original_angle = Angle
 	if(!nondirectional_sprite)
-		var/matrix/M = new
-		M.Turn(Angle)
-		transform = M
+		var/matrix/matrix = new
+		matrix.Turn(Angle)
+		transform = matrix
 	trajectory_ignore_forcemove = TRUE
 	forceMove(starting)
 	trajectory_ignore_forcemove = FALSE
@@ -692,23 +692,43 @@
 		START_PROCESSING(SSprojectiles, src)
 	pixel_move(1, FALSE) //move it now!
 
-/obj/projectile/proc/setAngle(new_angle) //wrapper for overrides.
+/obj/projectile/proc/set_angle(new_angle) //wrapper for overrides.
 	Angle = new_angle
 	if(!nondirectional_sprite)
-		var/matrix/M = new
-		M.Turn(Angle)
-		transform = M
+		var/matrix/matrix = new
+		matrix.Turn(Angle)
+		transform = matrix
 	if(trajectory)
 		trajectory.set_angle(new_angle)
 	if(fired && hitscan && isloc(loc) && (loc != last_angle_set_hitscan_store))
 		last_angle_set_hitscan_store = loc
-		var/datum/point/pcache = new (src)
-		var/list/coordinates = trajectory.return_coordinates()
-		pcache.initialize_location(coordinates[1], coordinates[2], coordinates[3]) // Take the center of the hitscan collision tile, so it looks good on reflector boxes and the like
-		trajectory.initialize_location(coordinates[1], coordinates[2], coordinates[3]) // Sets the trajectory to it as well, to prevent a strange visual bug
-		store_hitscan_collision(pcache)
+		var/datum/point/point_cache = new (src)
+		point_cache = trajectory.copy_to()
+		store_hitscan_collision(point_cache)
 	return TRUE
 
+/// Same as set_angle, but the reflection continues from the center of the object that reflects it instead of the side
+/obj/projectile/proc/set_angle_centered(new_angle)
+	Angle = new_angle
+	if(!nondirectional_sprite)
+		var/matrix/matrix = new
+		matrix.Turn(Angle)
+		transform = matrix
+	if(trajectory)
+		trajectory.set_angle(new_angle)
+	
+	var/list/coordinates = trajectory.return_coordinates()
+	trajectory.set_location(coordinates[1], coordinates[2], coordinates[3]) // Sets the trajectory to the center of the tile it bounced at
+
+	if(fired && hitscan && isloc(loc) && (loc != last_angle_set_hitscan_store)) // Handles hitscan projectiles
+		last_angle_set_hitscan_store = loc
+		var/datum/point/point_cache = new (src)
+		point_cache.initialize_location(coordinates[1], coordinates[2], coordinates[3]) // Take the center of the hitscan collision tile
+		store_hitscan_collision(point_cache)
+	return TRUE
+		
+
+
 /obj/projectile/forceMove(atom/target)
 	if(!isloc(target) || !isloc(loc) || !z)
 		return ..()
@@ -735,7 +755,7 @@
 /obj/projectile/vv_edit_var(var_name, var_value)
 	switch(var_name)
 		if(NAMEOF(src, Angle))
-			setAngle(var_value)
+			set_angle(var_value)
 			return TRUE
 		else
 			return ..()
@@ -746,10 +766,10 @@
 		return TRUE
 	return FALSE
 
-/obj/projectile/proc/record_hitscan_start(datum/point/pcache)
-	if(pcache)
+/obj/projectile/proc/record_hitscan_start(datum/point/point_cache)
+	if(point_cache)
 		beam_segments = list()
-		beam_index = pcache
+		beam_index = point_cache
 		beam_segments[beam_index] = null //record start.
 
 /obj/projectile/proc/process_hitscan()
@@ -772,9 +792,9 @@
 		return
 	last_projectile_move = world.time
 	if(!nondirectional_sprite && !hitscanning)
-		var/matrix/M = new
-		M.Turn(Angle)
-		transform = M
+		var/matrix/matrix = new
+		matrix.Turn(Angle)
+		transform = matrix
 	if(homing)
 		process_homing()
 	var/forcemoved = FALSE
@@ -814,7 +834,7 @@
 	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))
+	set_angle(Angle + clamp(angle, -homing_turn_speed, homing_turn_speed))
 
 /obj/projectile/proc/set_homing_target(atom/A)
 	if(!A || (!isturf(A) && !isturf(A.loc)))
@@ -840,18 +860,18 @@
 	if(targloc || !params)
 		yo = targloc.y - curloc.y
 		xo = targloc.x - curloc.x
-		setAngle(Get_Angle(src, targloc) + spread)
+		set_angle(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)
+		set_angle(calculated[1] + spread)
 	else if(targloc)
 		yo = targloc.y - curloc.y
 		xo = targloc.x - curloc.x
-		setAngle(Get_Angle(src, targloc) + spread)
+		set_angle(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)
@@ -902,8 +922,8 @@
 
 /obj/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
+		var/datum/point/point_cache = trajectory.copy_to()
+		beam_segments[beam_index] = point_cache
 	generate_hitscan_tracers(null, null, impacting)
 
 /obj/projectile/proc/generate_hitscan_tracers(cleanup = TRUE, duration = 3, impacting = TRUE)
@@ -917,9 +937,9 @@
 		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
+		var/matrix/matrix = new
+		matrix.Turn(original_angle)
+		thing.transform = matrix
 		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)
@@ -927,9 +947,9 @@
 		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
+		var/matrix/matrix = new
+		matrix.Turn(Angle)
+		thing.transform = matrix
 		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)