Fixed some logical issues with Enter() and LinkBlocked() procs

- LinkBlocked handles diagonal movement properly now

- Collisions with multitile vehicles will now prioritize border items when handling collisions

- Collisions with multitile vehicles will now destroy all blocking items instead of only the first one that is caught

- Set more can_block_movement values to optimize movement slightly

code/__DEFINES/movement.dm

@@ -1,6 +1,10 @@
 #define BLOCKED_MOVEMENT (NORTH|SOUTH|EAST|WEST)
 #define NO_BLOCKED_MOVEMENT 0
 
+/// Whether after Collide, movement is NOT blocked.
+/// Mainly for vehicles at the moment
+#define MOVABLE_COLLIDE_NOT_BLOCKED (1<<0)
+
 #define LOW_LAUNCH   0
 #define NORMAL_LAUNCH   1
 #define HIGH_LAUNCH  2

code/__HELPERS/unsorted.dm

@@ -130,106 +130,118 @@
 /proc/Get_Compass_Dir(atom/start, atom/end)//get_dir() only considers an object to be north/south/east/west if there is zero deviation. This uses rounding instead.
 	return angle_to_dir(Get_Angle(get_turf(start), get_turf(end)))
 
-// Among other things, used by flamethrower and boiler spray to calculate if flame/spray can pass through.
-// Returns an atom for specific effects (primarily flames and acid spray) that damage things upon contact
-//
-// This is a copy-and-paste of the Enter() proc for turfs with tweaks related to the applications
-// of LinkBlocked
+/**
+ * Among other things, used by flamethrower and boiler spray to calculate if flame/spray can pass through.
+ * Returns an atom for specific effects (primarily flames and acid spray) that damage things upon contact
+ *
+ * This is a copy-and-paste of the Enter() proc for turfs with tweaks related to the applications of LinkBlocked
+ */
 /proc/LinkBlocked(atom/movable/mover, turf/start_turf, turf/target_turf, list/atom/forget)
 	if (!mover)
 		return null
 
 	/// the actual dir between the start and target turf
-	var/fdir = get_dir(start_turf, target_turf)
-	if (!fdir)
+	var/target_dir = get_dir(start_turf, target_turf)
+	if (!target_dir)
 		return null
 
-	var/fd1 = fdir & (fdir-1)
-	var/fd2 = fdir - fd1
+	// NORTH or SOUTH component of target direction
+	var/longitudinal_dir = target_dir & (target_dir-1)
+	// EAST or WEST component of target direction
+	var/latitudinal_dir = target_dir - longitudinal_dir
 
 	/// The direction that mover's path is being blocked by
-	var/blocking_dir = 0
-
-	var/obstacle
-	var/turf/T
-	var/atom/A
-
-	blocking_dir |= start_turf.BlockedExitDirs(mover, fdir)
+	var/blocking_dir = NO_BLOCKED_MOVEMENT
+
+	var/turf/turf_to_check
+	var/atom/movable/obstacle
+
+	/**
+	 * Check atoms in the current turf (including turf itself)
+	 *
+	 * For each atom, including the current turf, we check:
+	 * 1. Whether that atom will allow us to exit in either the longitudinal
+	 * or latitudinal directions
+	 */
+	blocking_dir |= start_turf.BlockedExitDirs(mover, target_dir)
+	if (blocking_dir == target_dir)
+		return start_turf
 	for (obstacle in start_turf) //First, check objects to block exit
-		if (mover == obstacle || (obstacle in forget))
-			continue
 		if (!isStructure(obstacle) && !ismob(obstacle) && !isVehicle(obstacle))
 			continue
-		A = obstacle
-		blocking_dir |= A.BlockedExitDirs(mover, fdir)
-		if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-			return A
-
-	// Check for atoms in adjacent turf EAST/WEST
-	if (fd1 && fd1 != fdir)
-		T = get_step(start_turf, fd1)
-		if (T.BlockedExitDirs(mover, fd2) || T.BlockedPassDirs(mover, fd1))
-			blocking_dir |= fd1
-			if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-				return T
-		for (obstacle in T)
-			if(obstacle in forget)
-				continue
+		if (mover == obstacle || (obstacle in forget))
+			continue
+		blocking_dir |= obstacle.BlockedExitDirs(mover, target_dir)
+		if ((blocking_dir & target_dir) == target_dir)
+			return obstacle
+
+	/**
+	 * Check atoms in the adjacent turf (including turf itself) to the EAST or WEST when moving diagonally
+	 *
+	 * For each atom, including the turf to the EAST or WEST, we check:
+	 * 1. Whether that atom will block us from exiting into the target turf from its turf (by NORTH or SOUTH depending on latitudinal_dir)
+	 * 2. Whether that atom will block us from entering into its turf from the current turf (by EAST or WEST depending on longitudinal_dir)
+	 */
+	if (longitudinal_dir && longitudinal_dir != target_dir)
+		turf_to_check = get_step(start_turf, longitudinal_dir)
+		if (turf_to_check.BlockedExitDirs(mover, latitudinal_dir) || turf_to_check.BlockedPassDirs(mover, longitudinal_dir))
+			blocking_dir |= longitudinal_dir
+			if ((blocking_dir & target_dir) == target_dir)
+				return turf_to_check
+		for (obstacle in turf_to_check.movement_blockers)
 			if (!isStructure(obstacle) && !ismob(obstacle) && !isVehicle(obstacle))
 				continue
-			A = obstacle
-			if (A.BlockedExitDirs(mover, fd2) || A.BlockedPassDirs(mover, fd1))
-				blocking_dir |= fd1
-				if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-					return A
-				break
-
-	// Check for atoms in adjacent turf NORTH/SOUTH
-	if (fd2 && fd2 != fdir)
-		T = get_step(start_turf, fd2)
-		if (T.BlockedExitDirs(mover, fd1) || T.BlockedPassDirs(mover, fd2))
-			blocking_dir |= fd2
-			if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-				return T
-		for (obstacle in T)
-			if(obstacle in forget)
+			if (obstacle in forget)
 				continue
+			if (obstacle.BlockedExitDirs(mover, latitudinal_dir) || obstacle.BlockedPassDirs(mover, longitudinal_dir))
+				blocking_dir |= longitudinal_dir
+				if ((blocking_dir & target_dir) == target_dir)
+					return obstacle
+
+	/**
+	 * Check atoms in the adjacent turf (including turf itself) to the NORTH or SOUTH when moving diagonally
+	 *
+	 * For each atom, including the turf to the NORTH or SOUTH, we check:
+	 * 1. Whether that atom will block us from exiting into the target turf from its turf (by EAST or WEST depending on longitudinal_dir)
+	 * 2. Whether that atom will block us from entering into its turf from the current turf (by NORTH or SOUTH depending on latitudinal_dir)
+	 */
+	if (latitudinal_dir && latitudinal_dir != target_dir)
+		turf_to_check = get_step(start_turf, latitudinal_dir)
+		if (turf_to_check.BlockedExitDirs(mover, longitudinal_dir) || turf_to_check.BlockedPassDirs(mover, latitudinal_dir))
+			blocking_dir |= latitudinal_dir
+			if ((blocking_dir & target_dir) == target_dir)
+				return turf_to_check
+		for (obstacle in turf_to_check.movement_blockers)
 			if (!isStructure(obstacle) && !ismob(obstacle) && !isVehicle(obstacle))
 				continue
-			A = obstacle
-			if (A.BlockedExitDirs(mover, fd1) || A.BlockedPassDirs(mover, fd2))
-				blocking_dir |= fd2
-				if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-					return A
-				break
-
-	// Check the turf itself
-	blocking_dir |= target_turf.BlockedPassDirs(mover, fdir)
-	if ((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
+			if(obstacle in forget)
+				continue
+			if (obstacle.BlockedExitDirs(mover, longitudinal_dir) || obstacle.BlockedPassDirs(mover, latitudinal_dir))
+				blocking_dir |= latitudinal_dir
+				if ((blocking_dir & target_dir) == target_dir)
+					return obstacle
+
+	/**
+	 * Check atoms in the target turf (including turf itself)
+	 *
+	 * For each atom, including the target turf, we check:
+	 * 1. Whether that atom will allow us to enter in either the longitudinal or
+	 * latitudinal directions
+	 */
+	blocking_dir |= target_turf.BlockedPassDirs(mover, target_dir)
+	if ((blocking_dir & target_dir) == target_dir)
 		return target_turf
-	for (obstacle in target_turf) // Finally, check atoms in the target turf
-		if(obstacle in forget)
-			continue
-		if (!isStructure(obstacle) && !ismob(obstacle) && !isVehicle(obstacle))
+	for (obstacle in target_turf.movement_blockers) // Finally, check atoms in the target turf
+		if (obstacle in forget)
 			continue
-		A = obstacle
-		blocking_dir |= A.BlockedPassDirs(mover, fdir)
-		if((fd1 && blocking_dir == fd1) || (fd2 && blocking_dir == fd2))
-			return A
-		if((!fd1 || blocking_dir & fd1) && (!fd2 || blocking_dir & fd2))
-			return A
+		obstacle = obstacle
+		blocking_dir |= obstacle.BlockedPassDirs(mover, target_dir)
+		if((blocking_dir & target_dir) == target_dir)
+			return obstacle
 
 	return null // Nothing found to block the link of mover from start_turf to target_turf
 
 
-/proc/TurfBlockedNonWindow(turf/loc)
-	for(var/obj/O in loc)
-		if(O.density && !istype(O, /obj/structure/window))
-			return 1
-	return 0
-
-
-
 //Returns whether or not a player is a guest using their ckey as an input
 /proc/IsGuestKey(key)
 	if (findtext(key, "Guest-", 1, 7) != 1) //was findtextEx

code/game/atoms.dm

@@ -45,13 +45,13 @@
 	//Z-Level Transitions
 	var/atom/movable/clone/clone = null
 
-	// Bitflag of which test cases this atom is exempt from
-	// See #define/tests.dm
+	/**
+	 * Bitflag of which test cases this atom is exempt from
+	 *
+	 * See #define/tests.dm
+	 */
 	var/test_exemptions = 0
 
-	// Whether the atom is an obstacle that should be considered for passing
-	var/can_block_movement = FALSE
-
 	var/datum/component/orbiter/orbiters
 
 	///Reference to atom being orbited

code/game/atoms_movable.dm

@@ -11,10 +11,14 @@
 	var/mob/pulledby = null
 	var/rebounds = FALSE
 	var/rebounding = FALSE // whether an object that was launched was rebounded (to prevent infinite recursive loops from wall bouncing)
+	/// Whether the atom is an obstacle that should be considered for passing
+	var/can_block_movement = FALSE
 
-	var/acid_damage = 0 //Counter for stomach acid damage. At ~60 ticks, dissolved
+	/// Counter for stomach acid damage. At ~60 ticks, dissolved
+	var/acid_damage = 0
 
-	var/move_intentionally = FALSE // this is for some deep stuff optimization. This means that it is regular movement that can only be NSWE and you don't need to perform checks on diagonals. ALWAYS reset it back to FALSE when done
+	// this is for some deep stuff optimization. This means that it is regular movement that can only be NSWE and you don't need to perform checks on diagonals. ALWAYS reset it back to FALSE when done
+	var/move_intentionally = FALSE
 
 	/// How much this mob|object is worth when lowered into the ASRS pit while the black market is unlocked.
 	var/black_market_value = 0
@@ -92,6 +96,8 @@
 		AddComponent(/datum/component/overlay_lighting)
 	if(light_system == DIRECTIONAL_LIGHT)
 		AddComponent(/datum/component/overlay_lighting, is_directional = TRUE)
+	if(!mapload && isturf(loc))
+		loc.Entered(src)
 
 /atom/movable/proc/update_emissive_block()
 	if(emissive_overlay)

code/game/objects/effects/effect_system/particle_effects.dm

@@ -38,4 +38,4 @@
 /obj/effect/particle_effect/water/Collide(atom/A)
 	if(reagents)
 		reagents.reaction(A)
-	return ..()
+	return

code/game/objects/structures/signs.dm

@@ -3,6 +3,7 @@
 	anchored = TRUE
 	opacity = FALSE
 	density = FALSE
+	can_block_movement = FALSE
 	layer = WALL_OBJ_LAYER
 
 /obj/structure/sign/ex_act(severity)

code/game/objects/structures/window.dm

@@ -302,6 +302,12 @@
 /obj/structure/window/proc/is_full_window()
 	return !(flags_atom & ON_BORDER)
 
+/obj/structure/window/proc/destroy(play_sound = TRUE)
+	if (play_sound)
+		playsound(src, "windowshatter", 50, 1)
+	handle_debris()
+	qdel(src)
+
 /obj/structure/window/deconstruct(disassembled = TRUE)
 	if(disassembled)
 		if(reinf)

code/game/turfs/transit.dm

@@ -56,7 +56,7 @@
 			if(turf.density)
 				continue
 			var/found_dense = FALSE
-			for(var/atom/turf_atom in turf)
+			for(var/atom/movable/turf_atom in turf)
 				if(turf_atom.density && turf_atom.can_block_movement)
 					found_dense = TRUE
 					break