Makes viewers() defines (#82767)

code/__HELPERS/view.dm

@@ -20,8 +20,23 @@
 	view_info[2] *= world.icon_size
 	return view_info
 
-/proc/in_view_range(mob/user, atom/A)
-	var/list/view_range = getviewsize(user.client.view)
-	var/turf/source = get_turf(user)
-	var/turf/target = get_turf(A)
-	return ISINRANGE(target.x, source.x - view_range[1], source.x + view_range[1]) && ISINRANGE(target.y, source.y - view_range[1], source.y + view_range[1])
+/**
+* Frustrated with bugs in can_see(), this instead uses viewers for a much more effective approach.
+* ### Things to note:
+* - Src/source must be a mob. `viewers()` returns mobs.
+* - Adjacent objects are always considered visible.
+*/
+
+/// The default tile-distance between two atoms for one to consider the other as visible.
+#define DEFAULT_SIGHT_DISTANCE 7
+
+/// Basic check to see if the src object can see the target object.
+#define CAN_I_SEE(target) ((src in viewers(DEFAULT_SIGHT_DISTANCE, target)) || in_range(target, src))
+
+
+/// Checks the visibility between two other objects.
+#define CAN_THEY_SEE(target, source) ((source in viewers(DEFAULT_SIGHT_DISTANCE, target)) || in_range(target, source))
+
+
+/// Further checks distance between source and target.
+#define CAN_SEE_RANGED(target, source, dist) ((source in viewers(dist, target)) || in_range(target, source))

code/datums/components/fullauto.dm

@@ -249,7 +249,7 @@
 	if(get_dist(shooter, target) <= 0)
 		target = get_step(shooter, shooter.dir) //Shoot in the direction faced if the mouse is on the same tile as we are.
 		target_loc = target
-	else if(!in_view_range(shooter, target))
+	else if(!CAN_THEY_SEE(target, shooter))
 		stop_autofiring() //Elvis has left the building.
 		return FALSE
 	shooter.face_atom(target)

code/datums/components/ranged_mob_full_auto.dm

@@ -56,7 +56,7 @@
 	if (get_dist(living_parent, target) <= 0)
 		set_target(get_step(living_parent, living_parent.dir)) // Shoot in the direction faced if the mouse is on the same tile as we are.
 		target_loc = target
-	else if (!in_view_range(living_parent, target))
+	else if (!CAN_THEY_SEE(target, living_parent))
 		stop_firing()
 		return FALSE // Can't see shit
 

code/modules/projectiles/guns/energy/special.dm

@@ -409,7 +409,7 @@
 		COOLDOWN_START(src, coin_regen_cd, coin_regen_rate)
 
 /obj/item/gun/energy/marksman_revolver/afterattack_secondary(atom/target, mob/living/user, params)
-	if(!can_see(user, get_turf(target), length = 9))
+	if(!CAN_THEY_SEE(target, user))
 		return ..()
 
 	if(max_coins && coin_count <= 0)