Quadtrees shapes (#6681)

# About the pull request

Additional shapes available for testing against quadtrees or elsewhere:
square, ellipse, circle. Square is a simplified version of the
rectangle, circle is a simplified version of the ellipse.
Cleaned up existing code for shapes (rectangles), should be better
documented and easier to read.
Where possible converted existing RECT usage to SQUARE (everything was
squares anyway).
Where possible loosened defined types to the base `/datum/shape` so
shape types can be swapped as desired.

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# Explain why it's good for the game

Should (currently) have no effect on the game, but paves the way for
more interesting uses for quadtrees. Circular areas of effect, for
instance.
# Testing Photographs and Procedure
Boots. Sentries, flamer sentries, bell towers, flags, sentry laptop,
motion detector, and egg morpher all appear to work as intended.


# Changelog
No player facing changes.

code/_macros.dm

@@ -95,6 +95,9 @@
 #define GENERATE_DEBUG_ID "[rand(0, 9)][rand(0, 9)][rand(0, 9)][rand(0, 9)][pick(alphabet_lowercase)][pick(alphabet_lowercase)][pick(alphabet_lowercase)][pick(alphabet_lowercase)]"
 
 #define RECT new /datum/shape/rectangle
+#define SQUARE new /datum/shape/rectangle/square
+#define ELLIPSE new /datum/shape/ellipse
+#define CIRCLE new /datum/shape/ellipse/circle
 #define QTREE new /datum/quadtree
 #define SEARCH_QTREE(qtree, shape_range, flags) qtree.query_range(shape_range, null, flags)
 

code/controllers/subsystem/sound.dm

@@ -19,8 +19,7 @@ SUBSYSTEM_DEF(sound)
 		if(!run_hearers) // Initialize for handling next template
 			run_hearers = run_queue[run_template] // get base hearers
 			if(run_template.range) // ranging
-				var/datum/shape/rectangle/zone = RECT(run_template.x, run_template.y, run_template.range * 2, run_template.range * 2)
-				run_hearers |= SSquadtree.players_in_range(zone, run_template.z)
+				run_hearers |= SSquadtree.players_in_range(SQUARE(run_template.x, run_template.y, run_template.range), run_template.z)
 			if(MC_TICK_CHECK)
 				return
 		while(length(run_hearers)) // Output sound to hearers

code/datums/quadtree.dm

@@ -49,43 +49,124 @@
 	..()
 	return QDEL_HINT_IWILLGC
 
-/datum/shape //Leaving rectangles as a subtype if anyone decides to add circles later
+/// A simple geometric shape for testing collisions and intersections. This one is a single point.
+/datum/shape
+	/// Horizontal position of the shape's center point.
 	var/center_x = 0
+	/// Vertical position of the shape's center point.
 	var/center_y = 0
+	/// Distance from the shape's leftmost to rightmost extent.
+	var/bounds_x = 0
+	/// Distance from the shape's topmost to bottommost extent.
+	var/bounds_y = 0
 
-/datum/shape/proc/intersects()
-	return
-/datum/shape/proc/contains()
-	return
+/datum/shape/New(center_x, center_y)
+	set_shape(center_x, center_y)
 
+/// Assign shape variables.
+/datum/shape/proc/set_shape(center_x, center_y)
+	src.center_x = center_x
+	src.center_y = center_y
+
+/// Returns TRUE if the coordinates x, y are in or on the shape, otherwise FALSE.
+/datum/shape/proc/contains_xy(x, y)
+	return center_x == x && center_y == y
+
+/// Returns TRUE if the coord datum is in or on the shape, otherwise FALSE.
+/datum/shape/proc/contains_coords(datum/coords/coords)
+	return contains_xy(coords.x_pos, coords.y_pos)
+
+/// Returns TRUE if the atom is in or on the shape, otherwise FALSE.
+/datum/shape/proc/contains_atom(atom/atom)
+	return contains_xy(atom.x, atom.y)
+
+/// Returns TRUE if this shape's bounding box intersects the provided shape's bounding box, otherwise FALSE. Generally faster than a full intersection test.
+/datum/shape/proc/intersects_aabb(datum/shape/aabb)
+	return (abs(src.center_x - aabb.center_x) <= (src.bounds_x + aabb.bounds_x) * 0.5) && (abs(src.center_y - aabb.center_y) <= (src.bounds_x + aabb.bounds_x) * 0.5)
+
+/// Returns TRUE if this shape intersects the provided rectangle shape, otherwise FALSE.
+/datum/shape/proc/intersects_rect(datum/shape/rectangle/rect)
+	return rect.contains_xy(src.center_x, src.center_y)
+
+/// A simple geometric shape for testing collisions and intersections. This one is an axis-aligned rectangle.
 /datum/shape/rectangle
+	/// Distance from the shape's leftmost to rightmost extent.
+	var/width = 0
+	/// Distance from the shape's topmost to bottommost extent.
+	var/height = 0
+
+/datum/shape/rectangle/New(center_x, center_y, width, height)
+	set_shape(center_x, center_y, width, height)
+
+/datum/shape/rectangle/set_shape(center_x, center_y, width, height)
+	..()
+	src.bounds_x = width
+	src.bounds_y = height
+	src.width = width
+	src.height = height
+
+/datum/shape/rectangle/contains_xy(x, y)
+	return (abs(center_x - x) <= width * 0.5) && (abs(center_y - y) <= height * 0.5)
+
+/datum/shape/rectangle/intersects_rect(datum/shape/rectangle/rect)
+	return intersects_aabb(rect)
+
+/// A simple geometric shape for testing collisions and intersections. This one is an axis-aligned square.
+/datum/shape/rectangle/square
+	/// Distance between the shape's opposing extents.
+	var/length = 0
+
+/datum/shape/rectangle/square/New(center_x, center_y, length)
+	set_shape(center_x, center_y, length)
+
+/datum/shape/rectangle/square/set_shape(center_x, center_y, length)
+	..(center_x, center_y, length, length)
+	src.length = length
+
+/// A simple geometric shape for testing collisions and intersections. This one is an axis-aligned ellipse.
+/datum/shape/ellipse
+	/// Distance from the shape's leftmost to rightmost extent.
 	var/width = 0
+	/// Distance from the shape's topmost to bottommost extent.
 	var/height = 0
+	VAR_PROTECTED/_axis_x_sq = 0
+	VAR_PROTECTED/_axis_y_sq = 0
+
+/datum/shape/ellipse/New(center_x, center_y, width, height)
+	set_shape(center_x, center_y, width, height)
 
-/datum/shape/rectangle/New(x, y, w, h)
+/datum/shape/ellipse/set_shape(center_x, center_y, width, height)
 	..()
-	center_x = x
-	center_y = y
-	width = w
-	height = h
-
-/datum/shape/rectangle/intersects(datum/shape/rectangle/range)
-	return !(range.center_x + range.width/2 < center_x - width / 2|| \
-			range.center_x  - range.width/2 > center_x + width / 2|| \
-			range.center_y + range.height/2 < center_y - height / 2|| \
-			range.center_y - range.height/2 > center_y + height / 2)
-
-/datum/shape/rectangle/contains(datum/coords/coords)
-	return (coords.x_pos >= center_x - width / 2  \
-			&& coords.x_pos <= center_x + width / 2 \
-			&& coords.y_pos >= center_y - height /2  \
-			&& coords.y_pos <= center_y + height / 2)
-
-/datum/shape/rectangle/proc/contains_atom(atom/A)
-	return (A.x >= center_x - width / 2  \
-			&& A.x <= center_x + width / 2 \
-			&& A.y >= center_y - height /2  \
-			&& A.y <= center_y + height / 2)
+	src.bounds_x = width
+	src.bounds_y = height
+	src.width = width
+	src.height = height
+	src._axis_x_sq = (width * 0.5)**2
+	src._axis_y_sq = (height * 0.5)**2
+
+/datum/shape/ellipse/contains_xy(x, y)
+	return ((center_x - x)**2 / _axis_x_sq + (center_y - y)**2 / _axis_y_sq <= 1)
+
+/datum/shape/ellipse/intersects_rect(datum/shape/rectangle/rect)
+	if(..())
+		return TRUE
+
+	var/nearest_x = clamp(src.center_x, rect.center_x - rect.width * 0.5, rect.center_x + rect.width * 0.5)
+	var/nearest_y = clamp(src.center_y, rect.center_y - rect.height * 0.5, rect.center_y + rect.height * 0.5)
+
+	return src.contains_xy(nearest_x, nearest_y)
+
+/// A simple geometric shape for testing collisions and intersections. This one is a circle.
+/datum/shape/ellipse/circle
+	/// Distance from the shape's center to edge.
+	var/radius = 0
+
+/datum/shape/ellipse/circle/New(center_x, center_y, radius)
+	set_shape(center_x, center_y, radius)
+
+/datum/shape/ellipse/circle/set_shape(center_x, center_y, radius)
+	..(center_x, center_y, radius * 2, radius * 2)
+	src.radius = radius
 
 /datum/quadtree/proc/subdivide()
 	//Warning: this might give you eye cancer
@@ -96,7 +177,7 @@
 	is_divided = TRUE
 
 /datum/quadtree/proc/insert_player(datum/coords/qtplayer/p_coords)
-	if(!boundary.contains(p_coords))
+	if(!boundary.contains_coords(p_coords))
 		return FALSE
 
 	if(!player_coords)
@@ -118,11 +199,11 @@
 	player_coords.Add(p_coords)
 	return TRUE
 
-/datum/quadtree/proc/query_range(datum/shape/rectangle/range, list/found_players, flags = 0)
+/datum/quadtree/proc/query_range(datum/shape/range, list/found_players, flags = 0)
 	if(!found_players)
 		found_players = list()
 	. = found_players
-	if(!range?.intersects(boundary))
+	if(!range?.intersects_rect(boundary))
 		return
 	if(is_divided)
 		nw_branch.query_range(range, found_players, flags)
@@ -136,7 +217,7 @@
 			continue
 		if((flags & QTREE_EXCLUDE_OBSERVER) && P.is_observer)
 			continue
-		if(range.contains(P))
+		if(range.contains_coords(P))
 			if(flags & QTREE_SCAN_MOBS)
 				found_players.Add(P.player.mob)
 			else

code/game/camera_manager/camera_manager.dm

@@ -6,7 +6,7 @@
 /datum/component/camera_manager
 	var/map_name
 	var/obj/structure/machinery/camera/current
-	var/datum/shape/rectangle/current_area
+	var/datum/shape/current_area
 	var/atom/movable/screen/map_view/cam_screen
 	var/atom/movable/screen/background/cam_background
 	var/list/range_turfs = list()
@@ -86,7 +86,7 @@
 	RegisterSignal(parent, COMSIG_CAMERA_UNREGISTER_UI, PROC_REF(unregister))
 	RegisterSignal(parent, COMSIG_CAMERA_SET_NVG, PROC_REF(enable_nvg))
 	RegisterSignal(parent, COMSIG_CAMERA_CLEAR_NVG, PROC_REF(disable_nvg))
-	RegisterSignal(parent, COMSIG_CAMERA_SET_AREA, PROC_REF(set_camera_rect))
+	RegisterSignal(parent, COMSIG_CAMERA_SET_AREA, PROC_REF(set_camera_area))
 	RegisterSignal(parent, COMSIG_CAMERA_SET_TARGET, PROC_REF(set_camera))
 	RegisterSignal(parent, COMSIG_CAMERA_CLEAR, PROC_REF(clear_camera))
 	RegisterSignal(parent, COMSIG_CAMERA_REFRESH, PROC_REF(refresh_camera))
@@ -133,18 +133,18 @@
 	RegisterSignal(current, COMSIG_PARENT_QDELETING, PROC_REF(show_camera_static))
 	update_target_camera()
 
-/datum/component/camera_manager/proc/set_camera_rect(source, x, y, z, w, h)
+/datum/component/camera_manager/proc/set_camera_area(source, datum/shape/new_area, z)
 	SIGNAL_HANDLER
 	render_mode = RENDER_MODE_AREA
 	if(current)
 		UnregisterSignal(current, COMSIG_PARENT_QDELETING)
 	current = null
-	current_area = RECT(x, y, w, h)
-	target_x = x
-	target_y = y
+	current_area = new_area
+	target_x = current_area.center_x
+	target_y = current_area.center_y
 	target_z = z
-	target_width = w
-	target_height = h
+	target_width = current_area.bounds_x
+	target_height = current_area.bounds_y
 	update_area_camera()
 
 /datum/component/camera_manager/proc/enable_nvg(source, power, matrixcol)
@@ -221,8 +221,8 @@
 	// Cameras that get here are moving, and are likely attached to some moving atom such as cyborgs.
 	last_camera_turf = new_location
 
-	var/x_size = current_area.width
-	var/y_size = current_area.height
+	var/x_size = current_area.bounds_x
+	var/y_size = current_area.bounds_y
 	var/turf/target = locate(current_area.center_x, current_area.center_y, target_z)
 
 	var/list/visible_things = isXRay ? range("[x_size]x[y_size]", target) : view("[x_size]x[y_size]", target)

code/game/machinery/computer/dropship_weapons.dm

@@ -313,9 +313,8 @@
 					var/obj/structure/machinery/defenses/sentry/defense = sentry.deployed_turret
 					if(defense.has_camera)
 						defense.set_range()
-						var/datum/shape/rectangle/current_bb = defense.range_bounds
 						camera_area_equipment = sentry
-						SEND_SIGNAL(src, COMSIG_CAMERA_SET_AREA, current_bb.center_x, current_bb.center_y, defense.loc.z, current_bb.width, current_bb.height)
+						SEND_SIGNAL(src, COMSIG_CAMERA_SET_AREA, defense.range_bounds, defense.loc.z)
 				return TRUE
 
 		if("clear-camera")

code/game/objects/items/devices/motion_detector.dm

@@ -35,7 +35,7 @@
 	var/iff_signal = FACTION_MARINE
 	actions_types = list(/datum/action/item_action)
 	var/scanning = FALSE // controls if MD is in process of scan
-	var/datum/shape/rectangle/range_bounds
+	var/datum/shape/rectangle/square/range_bounds
 	var/long_range_locked = FALSE //only long-range MD
 	var/ping_overlay
 
@@ -48,7 +48,7 @@
 
 /obj/item/device/motiondetector/Initialize()
 	. = ..()
-	range_bounds = new //Just creating a rectangle datum
+	range_bounds = new //Just creating a square datum
 	update_icon()
 
 /obj/item/device/motiondetector/Destroy()
@@ -215,12 +215,7 @@
 	if(!istype(cur_turf))
 		return
 
-	if(!range_bounds)
-		range_bounds = new/datum/shape/rectangle
-	range_bounds.center_x = cur_turf.x
-	range_bounds.center_y = cur_turf.y
-	range_bounds.width = detector_range * 2
-	range_bounds.height = detector_range * 2
+	range_bounds.set_shape(cur_turf.x, cur_turf.y, detector_range * 2)
 
 	var/list/ping_candidates = SSquadtree.players_in_range(range_bounds, cur_turf.z, QTREE_EXCLUDE_OBSERVER | QTREE_SCAN_MOBS)
 

code/modules/cm_aliens/structures/special/egg_morpher.dm

@@ -14,14 +14,14 @@
 	var/huggers_to_grow_max = 12
 	var/huggers_reserved = 0
 	var/mob/captured_mob
-	var/datum/shape/rectangle/range_bounds
+	var/datum/shape/range_bounds
 
 	appearance_flags = KEEP_TOGETHER
 	layer = FACEHUGGER_LAYER
 
 /obj/effect/alien/resin/special/eggmorph/Initialize(mapload, hive_ref)
 	. = ..()
-	range_bounds = RECT(x, y, EGGMORPG_RANGE, EGGMORPG_RANGE)
+	range_bounds = SQUARE(x, y, EGGMORPG_RANGE)
 
 /obj/effect/alien/resin/special/eggmorph/Destroy()
 	if (stored_huggers && linked_hive)
@@ -158,7 +158,7 @@
 
 /obj/effect/alien/resin/special/eggmorph/proc/check_facehugger_target()
 	if(!range_bounds)
-		range_bounds = RECT(x, y, EGGMORPG_RANGE, EGGMORPG_RANGE)
+		range_bounds = SQUARE(x, y, EGGMORPG_RANGE)
 
 	var/list/targets = SSquadtree.players_in_range(range_bounds, z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
 	if(isnull(targets) || !length(targets))

code/modules/defenses/bell_tower.dm

@@ -257,7 +257,7 @@
 		STOP_PROCESSING(SSobj, src)
 		return
 
-	var/list/targets = SSquadtree.players_in_range(RECT(M.x, M.y, area_range, area_range), M.z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
+	var/list/targets = SSquadtree.players_in_range(SQUARE(M.x, M.y, area_range), M.z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
 	if(!targets)
 		return
 

code/modules/defenses/planted_flag.dm

@@ -7,7 +7,7 @@
 	desc = "A planted flag with the iconic USCM flag plastered all over it, you feel a burst of energy by its mere sight."
 	handheld_type = /obj/item/defenses/handheld/planted_flag
 	disassemble_time = 10
-	var/datum/shape/rectangle/range_bounds
+	var/datum/shape/range_bounds
 	var/area_range = PLANTED_FLAG_RANGE
 	var/buff_intensity = PLANTED_FLAG_BUFF
 	health = 200
@@ -33,7 +33,7 @@
 		apply_area_effect()
 		start_processing()
 
-	range_bounds = RECT(x, y, PLANTED_FLAG_RANGE, PLANTED_FLAG_RANGE)
+	range_bounds = SQUARE(x, y, PLANTED_FLAG_RANGE)
 	update_icon()
 
 /obj/structure/machinery/defenses/planted_flag/Destroy()
@@ -70,9 +70,9 @@
 
 /obj/structure/machinery/defenses/planted_flag/proc/apply_area_effect()
 	if(!range_bounds)
-		range_bounds = RECT(x, y, area_range, area_range)
+		range_bounds = SQUARE(x, y, area_range)
 
-	var/list/targets = SSquadtree.players_in_range(RECT(x, y, area_range, area_range), z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
+	var/list/targets = SSquadtree.players_in_range(SQUARE(x, y, area_range), z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
 	if(!targets)
 		return
 
@@ -180,7 +180,7 @@
 	if(!M.x && !M.y && !M.z)
 		return
 
-	var/list/targets = SSquadtree.players_in_range(RECT(M.x, M.y, area_range, area_range), M.z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
+	var/list/targets = SSquadtree.players_in_range(SQUARE(M.x, M.y, area_range), M.z, QTREE_SCAN_MOBS | QTREE_EXCLUDE_OBSERVER)
 	targets |= M
 
 	for(var/mob/living/carbon/human/H in targets)