Add Space.GetBodiesNear(), ProximityQuery module

data/libs/SpaceStation.lua

@@ -941,7 +941,7 @@ function SpaceStation:UnlockAdvert (ref)
 end
 
 local function updateSystem ()
-	local stations = Space.GetBodies(function (b) return b.superType == "STARPORT" end)
+	local stations = Space.GetBodies("SpaceStation")
 	for i, station in ipairs(stations) do
 		-- updateStationMarket(station)
 		Economy.UpdateStationMarket(station:GetSystemBody())

data/meta/Space.lua

@@ -0,0 +1,28 @@
+-- Copyright © 2008-2023 Pioneer Developers. See AUTHORS.txt for details
+-- Licensed under the terms of the GPL v3. See licenses/GPL-3.txt
+
+-- This file implements type information about C++ classes for Lua static analysis
+
+---@meta
+
+local Space = {}
+
+package.core["Space"] = Space
+
+-- Returns a list of bodies simulated in the current system, optionally filtered by type
+---@generic T
+---@param class `T` an optional body classname to filter the returned results by
+---@return T[]
+---@overload fun(): Body[]
+function Space.GetBodies(class) end
+
+-- Returns a list of bodies at most dist away from the given body, optionally filtered by type
+---@generic T
+---@param body Body the reference body
+---@param dist number the maximum distance from the reference body to search
+---@param filter `T` an optional body classname to filter the returned results by
+---@return T[]
+---@overload fun(body: Body, dist: number): Body[]
+function Space.GetBodiesNear(body, dist, filter) end
+
+return Space

data/modules/Assassination/Assassination.lua

@@ -388,7 +388,7 @@ local onShipUndocked = function (ship, station)
 	for ref,mission in pairs(missions) do
 		if mission.status == 'ACTIVE' and
 		   mission.ship == ship then
-			planets = Space.GetBodies(function (body) return body:isa("Planet") end)
+			planets = Space.GetBodies("Planet")
 			if #planets == 0 then
 				ship:AIFlyTo(station)
 				mission.shipstate = 'outbound'

data/modules/BulkShips.lua

@@ -19,7 +19,7 @@ local spawnShips = function ()
 		return
 	end
 
-	local stations = Space.GetBodies(function (body) return body:isa("SpaceStation") and not body.isGroundStation end)
+	local stations = utils.filter_array(Space.GetBodies("SpaceStation"), function (body) return not body.isGroundStation end)
 	if #stations == 0 then
 		return
 	end

data/modules/Common/ProximityQuery.lua

@@ -0,0 +1,139 @@
+-- Copyright © 2008-2023 Pioneer Developers. See AUTHORS.txt for details
+-- Licensed under the terms of the GPL v3. See licenses/GPL-3.txt
+
+local Engine     = require 'Engine'
+local Space      = require 'Space'
+local Timer      = require 'Timer'
+local utils      = require 'utils'
+local Game       = require 'Game'
+
+local ProximityQuery = {}
+
+-- ─── Context ─────────────────────────────────────────────────────────────────
+
+local onBodyEnter = function(ctx, enter) end
+local onBodyLeave = function(ctx, leave) end
+
+-- List of bodies currently in proximity is stored with weak keys, so deleted
+-- bodies are quietly cleaned up during a GC cycle
+local bodyListMt = {
+	__mode = "k"
+}
+
+---@class ProximityQuery.Context
+---@field New fun(body, dist, interval, type): self
+---@field body Body
+---@field dist number
+local Context = utils.class 'ProximityQuery.Context'
+
+function Context:Constructor(body, dist, type)
+	self.bodies = setmetatable({}, bodyListMt)
+	self.body = body
+	self.dist = dist
+	self.filter = type
+	self.iter = 0
+
+	self.onBodyEnter = onBodyEnter
+	self.onBodyLeave = onBodyLeave
+end
+
+function Context:Cancel()
+	self.iter = nil
+end
+
+---@param fn fun(ctx: ProximityQuery.Context, enter: Body)
+function Context:SetBodyEnter(fn)
+	self.onBodyEnter = fn
+	return self
+end
+
+---@param fn fun(ctx: ProximityQuery.Context, leave: Body)
+function Context:SetBodyLeave(fn)
+	self.onBodyLeave = fn
+	return self
+end
+
+-- Class: ProximityQuery
+--
+-- This class provides a helper utility to allow using Space.GetBodiesNear() in
+-- an efficient manner, providing an event-based API when bodies enter or leave
+-- a user-specified relevancy range of the reference body.
+
+-- Function: CreateQuery
+--
+-- Register a new periodic proximity test relative to the given body
+--
+-- Parameters:
+--
+--   body     - the reference body to perform testing for
+--   dist     - the distance (in meters) of the proximity test to perform
+--   interval - how often a proximity test should be performed in seconds.
+--              Smaller values are more performance-hungry.
+--   type     - optional body classname filter, see Space.GetBodiesNear
+--   overlap  - if false, all bodies of type in the radius will generate
+--                initial proximity events on the first proximity test
+--
+-- Returns:
+--
+--   context - the context object for the registered test
+--
+function ProximityQuery.CreateQuery(body, dist, interval, type, overlap)
+	local context = Context.New(body, dist, type)
+	local cb = ProximityQuery.MakeCallback(context)
+
+	-- Queue the start of the timer at a random timestamp inside the first interval period
+	-- This provides natural load balancing for large numbers of callbacks created on the same frame
+	-- (e.g. at game start / hyperspace entry)
+	Timer:CallAt(Game.time + Engine.rand:Number(interval), function()
+
+		if overlap == false then
+			cb()
+		else
+			-- Pre-fill the list of nearby bodies (avoid spurious onBodyEnter() callbacks when creating)
+			for i, locBody in ipairs(Space.GetBodiesNear(body, dist, type)) do
+				context.bodies[locBody] = context.iter
+			end
+		end
+
+		Timer:CallEvery(interval, cb)
+	end)
+
+	return context
+end
+
+---@private
+---@param context ProximityQuery.Context
+function ProximityQuery.MakeCallback(context)
+	return function()
+		-- Callback has been cancelled or query body no longer exists,
+		-- stop ticking this query
+		if not context.iter or not context.body:exists() then
+			return true
+		end
+
+		local newIter = (context.iter + 1) % 2
+		context.iter = newIter
+
+		for i, locBody in ipairs(Space.GetBodiesNear(context.body, context.dist, context.filter)) do
+			if not context.bodies[locBody] then
+				context.onBodyEnter(context, locBody)
+			end
+
+			context.bodies[locBody] = newIter
+		end
+
+		local remove = {}
+		for locBody, ver in pairs(context.bodies) do
+			if ver ~= newIter then
+				context.onBodyLeave(context, locBody)
+				table.insert(remove, locBody)
+			end
+		end
+
+		for _, v in ipairs(remove) do
+			context.bodies[v] = nil
+		end
+	end
+end
+
+return ProximityQuery

data/modules/SearchRescue/SearchRescue.lua

@@ -301,7 +301,7 @@ local triggerAdCreation = function ()
 	-- Return if ad should be created based on lawlessness and min/max frequency values.
 	-- Ad number per system is based on how many stations a system has so a player will
 	-- be met with a certain number of stations that have one or more ads.
-	local stations = Space.GetBodies(function (body) return body.superType == 'STARPORT' end)
+	local stations = Space.GetBodies("SpaceStation")
 	local freq = Game.system.lawlessness * ad_freq_max
 	if freq < ad_freq_min then freq = ad_freq_min end
 	local ad_num_max = freq * #stations
@@ -1001,10 +1001,11 @@ local findNearbyStations = function (vacuum, body)
 	-- get station bodies within current system depending on vacuum variable
 	local nearbystations_raw
 	if vacuum == true then
-		nearbystations_raw = Space.GetBodies(function (body)
-				return body.superType == 'STARPORT' and (body.type == 'STARPORT_ORBITAL' or (not body.path:GetSystemBody().parent.hasAtmosphere)) end)
+		nearbystations_raw = utils.filter_array(Space.GetBodies("SpaceStation"), function (body)
+			return body.type == 'STARPORT_ORBITAL' or (not body.path:GetSystemBody().parent.hasAtmosphere)
+		end)
 	else
-		nearbystations_raw = Space.GetBodies(function (body) return body.superType == 'STARPORT' end)
+		nearbystations_raw = Space.GetBodies("SpaceStation")
 	end
 
 	-- determine distance to body
@@ -1040,7 +1041,7 @@ local findClosestPlanets = function ()
 	end
 
 	-- get planets with stations and remove from planet list
-	local ground_stations = Space.GetBodies(function (body) return body.type == 'STARPORT_SURFACE' end)
+	local ground_stations = utils.filter_array(Space.GetBodies("SpaceStation"), function (body) return body.type == 'STARPORT_SURFACE' end)
 	for _,ground_station in pairs(ground_stations) do
 		for i=#rockyplanets, 1, -1 do
 			if rockyplanets[i] == Space.GetBody(ground_station.path:GetSystemBody().parent.index) then
@@ -1052,7 +1053,7 @@ local findClosestPlanets = function ()
 
 	-- create dictionary of stations
 	local closestplanets = {}
-	local stations = Space.GetBodies(function (body) return body.superType == 'STARPORT' end)
+	local stations = Space.GetBodies("SpaceStation")
 	for _,station in pairs(stations) do closestplanets[station] = {} end
 
 	-- pick closest planets to stations
@@ -1299,7 +1300,7 @@ local makeAdvert = function (station, manualFlavour, closestplanets)
 	local needed_fuel
 	if flavour.id == 2 or flavour.id == 5 then
 		needed_fuel = math.max(math.floor(shipdef.fuelTankMass * 0.1), 1)
-	elseif flavour.id == 4 then -- different planet 
+	elseif flavour.id == 4 then -- different planet
 		needed_fuel = math.max(math.floor(shipdef.fuelTankMass * 0.5), 1)
 	end
 	deliver_comm[Commodities.hydrogen] = needed_fuel

data/modules/System/Explore.lua

@@ -7,13 +7,14 @@ local Event = require 'Event'
 local Comms = require 'Comms'
 local Timer = require 'Timer'
 local Lang = require 'Lang'
+local utils = require 'utils'
 
 local l = Lang.GetResource("module-system")
 
 local exploreSystem = function (system)
 	Comms.Message(l.GETTING_SENSOR_DATA)
-	local starports = #Space.GetBodies(function (body) return body.superType == 'STARPORT' end)
-	local major_bodies = #Space.GetBodies(function (body) return body.superType and body.superType ~= 'STARPORT' and body.superType ~= 'NONE' end)
+	local starports = #Space.GetBodies("SpaceStation")
+	local major_bodies = #Space.GetBodies("TerrainBody")
 	local bodies
 	if major_bodies == 1 then
 		bodies = l.BODY

data/modules/TradeShips/Debug.lua

@@ -108,7 +108,7 @@ debugView.registerTab('debug-trade-ships', function()
 			ui.sameLine()
 			property("Lawlessness", string.format("%.4f", Game.system.lawlessness))
 			ui.sameLine()
-			property("Total bodies in space", #Space.GetBodies())
+			property("Total bodies in space", Space.GetNumBodies())
 		end
 
 		if ui.collapsingHeader("Stations") then

data/modules/TradeShips/Flow.lua

@@ -108,7 +108,7 @@ Flow.calculateSystemParams = function()
 	if system.population == 0 then return nil end
 
 	-- all ports in the system
-	local ports = Space.GetBodies(function (body) return body.superType == 'STARPORT' end)
+	local ports = Space.GetBodies("SpaceStation")
 	-- check if the current system can be traded in
 	if #ports == 0 then return nil end
 

src/lua/LuaBody.cpp

@@ -27,12 +27,31 @@
 #include "SpaceStation.h"
 #include "Star.h"
 
+// For LuaFlags<ObjectType>
+#include "enum_table.h"
+#include "pigui/LuaFlags.h"
+
 namespace PiGui {
 	// Declared in LuaPiGuiInternal.h
 	extern bool first_body_is_more_important_than(Body *, Body *);
 	extern int pushOnScreenPositionDirection(lua_State *l, vector3d position);
 } // namespace PiGui
 
+static LuaFlags<ObjectType> s_bodyFlags ({
+	{ "Body", ObjectType::BODY },
+	{ "ModelBody", ObjectType::MODELBODY },
+	{ "Ship", ObjectType::SHIP },
+	{ "Player", ObjectType::PLAYER },
+	{ "SpaceStation", ObjectType::SPACESTATION },
+	{ "TerrainBody", ObjectType::TERRAINBODY },
+	{ "Planet", ObjectType::PLANET },
+	{ "Star", ObjectType::STAR },
+	{ "CargoBody", ObjectType::CARGOBODY },
+	{ "Projectile", ObjectType::PROJECTILE },
+	{ "Missile", ObjectType::MISSILE },
+	{ "HyperspaceCloud", ObjectType::HYPERSPACECLOUD }
+});
+
 /*
  * Class: Body
  *
@@ -843,6 +862,16 @@ static int l_body_set_ang_velocity(lua_State *l)
 	return 0;
 }
 
+void pi_lua_generic_pull(lua_State *l, int index, ObjectType &objectType)
+{
+	objectType = s_bodyFlags.LookupEnum(l, index);
+}
+
+void pi_lua_generic_push(lua_State *l, ObjectType bodyType)
+{
+	lua_pushstring(l, EnumStrings::GetString("PhysicsObjectType", static_cast<int>(bodyType)));
+}
+
 template <>
 const char *LuaObject<Body>::s_type = "Body";
 
@@ -908,4 +937,6 @@ void LuaObject<Body>::RegisterClass()
 	LuaObjectBase::RegisterSerializer("CargoBody", body_serializers);
 	LuaObjectBase::RegisterSerializer("Missile", body_serializers);
 	LuaObjectBase::RegisterSerializer("HyperspaceCloud", body_serializers);
+
+	s_bodyFlags.Register(Lua::manager->GetLuaState(), "Constants.ObjectType");
 }

src/lua/LuaBody.h

@@ -0,0 +1,9 @@
+// Copyright © 2008-2023 Pioneer Developers. See AUTHORS.txt for details
+// Licensed under the terms of the GPL v3. See licenses/GPL-3.txt
+
+#include "Body.h"
+#include "Lua.h"
+#include "LuaPushPull.h"
+
+void pi_lua_generic_pull(lua_State *l, int index, ObjectType &bodyType);
+void pi_lua_generic_push(lua_State *l, ObjectType bodyType);

src/lua/LuaPiGui.cpp

@@ -111,7 +111,7 @@ static Type parse_imgui_enum(lua_State *l, int index, LuaFlags<Type> lookupTable
 		return static_cast<Type>(lua_tointeger(l, index));
 	else {
 		luaL_traceback(l, l, NULL, 1);
-		Error("Expected a table or integer, got %s.\n%s\n", luaL_typename(l, index), lua_tostring(l, -1));
+		Error("Expected a string or integer, got %s.\n%s\n", luaL_typename(l, index), lua_tostring(l, -1));
 	}
 	return static_cast<Type>(0);
 }