chore(prototype): remove GUI position flip; MovePath exchange refused on both threads

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

mod/content/overtake_probe.script.tl

@@ -1,14 +1,11 @@
--- PROTOTYPE (ticket "Can a script swap the positions of a follower and its leader?"): throwaway,
--- lives only on branch prototype/vehicle-probe.
--- Engine thread: every INTERVAL it logs every player-owned road vehicle (segment, lane, position, speed).
--- GUI thread: EXPERIMENT flipping the positions of a follower and its leader (see below).
--- Earlier experiments (timeToIgnore, engine-side jump, set-line, segment rebuild) are in git history and
+-- PROTOTYPE: throwaway, lives only on branch prototype/vehicle-probe.
+-- Every INTERVAL it logs every player-owned road vehicle (segment, lane, position, speed).
+-- All experiments (timeToIgnore, jump, set-line, segment rebuild, GUI position flip) are in git history and
 -- docs/research/vehicle-probe.md; none moved a vehicle past another on a single-lane road.
 -- ponytail: module-local timer, not GameScriptState; fine for a probe (state resets between calls anyway).
 
 local TAG = "[overtake_probe] "
 local INTERVAL = 2.0
-local MAX_GAP = 40.0
 local elapsed = 0.0
 local ticks = 0
 
@@ -29,14 +26,6 @@ local function turnaround(edge : EdgeId) : integer
 	return tn.turnaroundEdges[edge.index + 1]
 end
 
-local record Car
-	v : integer
-	pos : number
-	pos01 : number
-	speed : number
-	dir : boolean
-end
-
 local function dump(dt : number)
 	local player = api.engine.util.getPlayer()
 	local vehicles = api.engine.getEntitiesWithComponent(api.type.ComponentType.TRANSPORT_VEHICLE, { requireOwnedByPlayer = player })
@@ -56,94 +45,7 @@ local function dump(dt : number)
 	end
 end
 
--- EXPERIMENT (GUI thread, where sendCommand callbacks work): flip the positions of a follower and its leader by
--- exchanging their MovePath components (route + position) with api.cmd.debug.makeComponentExchangeCmd.
-local MAX_FLIPS = 2
-local FLIP_SCAN_FRAMES = 60 -- scan for a pair about once per second
-local FLIP_TRACE_FRAMES = 600 -- then log both vehicles every 10 frames for ~10 s
-
-local record GuiState
-	frames : integer
-	flips : integer
-	traceLeft : integer
-	a : integer
-	b : integer
-end
-
-local function movePathOf(v : integer) : Engine.Component.MovePath
-	return api.engine.getComponent(v, api.type.ComponentType.MOVE_PATH) as Engine.Component.MovePath
-end
-
-local function flipLine(v : integer) : string
-	local mp = movePathOf(v)
-	if mp == nil then return "veh=" .. v .. " no MovePath" end
-	local edge, _dir = edgeAt(mp)
-	return string.format("veh=%d seg=%s lane=%s pos=%.1f v=%.2f", v, tostring(edge and edge.entity), tostring(edge and edge.index), mp.dyn.pathPos.pos, mp.dyn.speed)
-end
-
-local function sendFlip(gs : GuiState, follower : integer, leader : integer)
-	local mpF, mpL = movePathOf(follower), movePathOf(leader)
-	p("FLIP_TEST before " .. flipLine(follower) .. " | " .. flipLine(leader))
-	local function done(label : string) : function(any, boolean)
-		return function(res : any, success : boolean)
-			p(string.format("FLIP_TEST result %s success=%s res=%s", label, tostring(success), tostring(res)))
-		end
-	end
-	api.cmd.sendCommand(api.cmd.debug.makeComponentExchangeCmd(follower, mpL as Engine.Component), done("follower<-leader"))
-	api.cmd.sendCommand(api.cmd.debug.makeComponentExchangeCmd(leader, mpF as Engine.Component), done("leader<-follower"))
-	gs.flips = gs.flips + 1
-	gs.traceLeft = FLIP_TRACE_FRAMES
-	gs.a, gs.b = follower, leader
-end
-
--- same pair rule as the engine-side probe: same segment + lane, follower < MAX_GAP behind a moving leader
-local function findPair() : integer, integer
-	local player = api.engine.util.getPlayer()
-	local byLane : {string : {Car}} = {}
-	for _, v in ipairs(api.engine.getEntitiesWithComponent(api.type.ComponentType.TRANSPORT_VEHICLE, { requireOwnedByPlayer = player })) do
-		local lv = api.engine.getComponent(v, api.type.ComponentType.LAND_VEHICLE) as Engine.Component.LandVehicle
-		local mp = movePathOf(v)
-		if lv ~= nil and not lv.isTram and mp ~= nil then
-			local edge, dir = edgeAt(mp)
-			if edge ~= nil then
-				local key = edge.entity .. ":" .. edge.index
-				byLane[key] = byLane[key] or {}
-				table.insert(byLane[key], { v = v, pos = mp.dyn.pathPos.pos, pos01 = mp.dyn.pathPos.pos01, speed = mp.dyn.speed, dir = dir })
-			end
-		end
-	end
-	for _, cars in pairs(byLane) do
-		for i = 1, #cars do
-			for j = 1, #cars do
-				local a, b = cars[i], cars[j]
-				local ahead = (a.dir and b.pos > a.pos) or (not a.dir and b.pos < a.pos)
-				if i ~= j and ahead and math.abs(b.pos - a.pos) < MAX_GAP and b.speed > 1.0 then
-					return a.v, b.v
-				end
-			end
-		end
-	end
-	return nil, nil
-end
-
-local function guiStep(gsState : GameScriptState<GuiState>)
-	local gs = gsState:get()
-	gs.frames = (gs.frames or 0) + 1
-	gs.flips = gs.flips or 0
-	gs.traceLeft = gs.traceLeft or 0
-	if gs.traceLeft > 0 then
-		if gs.traceLeft % 10 == 0 then
-			p(string.format("FLIP_TRACE f=%d %s | %s", FLIP_TRACE_FRAMES - gs.traceLeft, flipLine(gs.a), flipLine(gs.b)))
-		end
-		gs.traceLeft = gs.traceLeft - 1
-	elseif gs.flips < MAX_FLIPS and gs.frames % FLIP_SCAN_FRAMES == 0 then
-		local follower, leader = findPair()
-		if follower ~= nil then sendFlip(gs, follower, leader) end
-	end
-	gsState:set(gs)
-end
-
-local ret : GameScriptWithGui<table, GuiState> = {
+local ret : GameScript<table> = {
 	update = function(_userParams : table, _state : GameScriptState<table>, dt : number) : nil
 		ticks = ticks + 1
 		elapsed = elapsed + dt
@@ -152,9 +54,6 @@ local ret : GameScriptWithGui<table, GuiState> = {
 		elapsed = 0.0
 		xpcall(dump, function(err : any) p("ERROR " .. tostring(err)) end, dt)
 	end,
-	guiUpdate = function(_userParams : table, _state : GameScriptStateReadOnly<table>, guiState : GameScriptState<GuiState>)
-		xpcall(guiStep, function(err : any) p("ERROR gui " .. tostring(err)) end, guiState)
-	end,
 }
 
 return ret