chore(prototype): try re-path via makeVehicleSetLineCmd; record failed rebuild

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

docs/research/vehicle-probe.md

@@ -46,3 +46,9 @@ Ticket "Probe vehicle data and native passing in game" (part of map "Map: TpF3 o
 ## Decision
 
 Overtaking on two-way roads (one lane per direction) is dropped (decided by the user, 2026-10-05). The effort continues on multilane roads only: a held-back vehicle should switch to a lane the slower vehicle isn't in.
+
+## Segment rebuild (ticket "Can rebuilding a road segment move a passer past its blocker?")
+
+- The script sent 3 `makeWorldBuildProposalCmd` proposals (remove segment + re-add a copy of its `BaseEdge`/`BaseEdgeStreet`, `ignoreErrors = true`) for segments 29701 and 29699 (`country_new_medium`). **None took effect**: both segment ids stayed in use by vehicles until the end of the log, and 29699 was "rebuilt" twice. The game logged no error, and there's no callback in engine state. The copied `BaseEdge.distance` read `0.0`, so the copy is probably incomplete. A next attempt would need `api.engine.util.proposal.makeProposalData` to see the proposal's errors.
+- The human's manual segment deletion left no trace in the probe data: every vehicle stayed `tvState=1` (en route), with only normal path trimming.
+- Related find: `api.cmd.makeVehicleSendToDepotCmd(vehicle, sellOnArrival, jumpToDepotEntity)` "teleports" a vehicle to a depot. The engine can relocate vehicles instantly, but only to depots.

mod/content/overtake_probe.script.tl

@@ -8,7 +8,8 @@
 local TAG = "[overtake_probe] "
 local INTERVAL = 2.0
 local MAX_GAP = 40.0
-local MAX_REBUILDS = 3 -- per save; counted in GameScriptState because module locals don't persist
+local MAX_REBUILDS = 0 -- rebuild disabled: proposals were silently rejected (segments kept their ids)
+local MAX_SETLINES = 5 -- EXPERIMENT: re-assign the follower to its own line + current stop to force a re-path
 local elapsed = 0.0
 local ticks = 0
 
@@ -38,6 +39,7 @@ end
 
 local record ProbeState
 	rebuilds : integer
+	setlines : integer
 	watch : {integer} -- vehicles involved in the last rebuild, flagged in later dumps
 end
 
@@ -78,16 +80,34 @@ local function rebuild(seg : integer)
 	api.cmd.sendCommand(api.cmd.makeWorldBuildProposalCmd(proposal, nil, true, false))
 end
 
+-- lanes of the next few path edges, to see whether a re-path changes the lane choice
+local function lanesAhead(mp : Engine.Component.MovePath) : string
+	local out : {string} = {}
+	local edges = mp.path.edges as {any}
+	for k = mp.dyn.pathPos.edgeIndex + 1, math.min(#edges, mp.dyn.pathPos.edgeIndex + 4) do
+		local e = edges[k] as UtilPathfinding.EdgeIdDir
+		table.insert(out, e.edgeId.entity .. ":" .. e.edgeId.index)
+	end
+	return table.concat(out, " ")
+end
+
+local function setLine(v : integer)
+	local tv = api.engine.getComponent(v, api.type.ComponentType.TRANSPORT_VEHICLE) as Engine.Component.TransportVehicle
+	p(string.format("SETLINE_TEST send veh=%d line=%s stopIndex=%s", v, tostring(tv.line), tostring(tv.stopIndex)))
+	api.cmd.sendCommand(api.cmd.makeVehicleSetLineCmd(v, tv.line, tv.stopIndex))
+end
+
 local function dump(dt : number, state : GameScriptState<ProbeState>)
 	local st = state:get()
 	st.rebuilds = st.rebuilds or 0
+	st.setlines = st.setlines or 0
 	st.watch = st.watch or {}
 	local watched : {integer : boolean} = {}
 	for _, w in ipairs(st.watch) do watched[w] = true end
 
 	local player = api.engine.util.getPlayer()
 	local vehicles = api.engine.getEntitiesWithComponent(api.type.ComponentType.TRANSPORT_VEHICLE, { requireOwnedByPlayer = player })
-	p(string.format("tick=%d dt=%s playerVehicles=%d rebuilds=%d", ticks, tostring(dt), #vehicles, st.rebuilds))
+	p(string.format("tick=%d dt=%s playerVehicles=%d rebuilds=%d setlines=%d", ticks, tostring(dt), #vehicles, st.rebuilds, st.setlines))
 
 	local byLane : {string : {Car}} = {}
 	local laneSeg : {string : integer} = {}
@@ -103,6 +123,7 @@ local function dump(dt : number, state : GameScriptState<ProbeState>)
 				watched[v] and "WATCH " or "", v, seg, tostring(edge and edge.index), tostring(dir), tostring(edge and turnaround(edge)),
 				mp.dyn.pathPos.edgeIndex, #(mp.path.edges as {any}), mp.dyn.pathPos.pos, mp.dyn.speed, tostring(mp.state),
 				tostring(tv and tv.state), tostring(tv and tv.line), mp.dyn.timeStanding))
+			if watched[v] then p("WATCH   lanesAhead veh=" .. v .. " " .. lanesAhead(mp)) end
 			if edge ~= nil then
 				local key = seg .. ":" .. edge.index
 				byLane[key] = byLane[key] or {}
@@ -112,7 +133,7 @@ local function dump(dt : number, state : GameScriptState<ProbeState>)
 		end
 	end
 
-	if st.rebuilds >= MAX_REBUILDS then return end
+	if st.rebuilds >= MAX_REBUILDS and st.setlines >= MAX_SETLINES then return end
 	for key, cars in pairs(byLane) do
 		for i = 1, #cars do
 			for j = 1, #cars do
@@ -122,6 +143,17 @@ local function dump(dt : number, state : GameScriptState<ProbeState>)
 				-- leader must be moving, otherwise it's a queue at a stop or junction, not a slow vehicle
 				if i ~= j and ahead and math.abs(b.pos - a.pos) < MAX_GAP and b.speed > 1.0 then
 					local seg = laneSeg[key]
+					if st.setlines < MAX_SETLINES then
+						local amp = api.engine.getComponent(a.v, api.type.ComponentType.MOVE_PATH) as Engine.Component.MovePath
+						p(string.format("SETLINE_TEST candidate seg=%d follower=%d (v=%.2f) leader=%d (v=%.2f) lanesAhead before: %s",
+							seg, a.v, a.speed, b.v, b.speed, lanesAhead(amp)))
+						setLine(a.v)
+						st.setlines = st.setlines + 1
+						st.watch = { a.v, b.v }
+						state:set(st)
+						return -- one experiment per dump
+					end
+					if st.rebuilds >= MAX_REBUILDS then return end
 					local ok, why = rebuildable(seg)
 					p(string.format("REBUILD_TEST candidate seg=%d follower=%d (pos=%.1f v=%.2f) leader=%d (pos=%.1f v=%.2f) ok=%s %s",
 						seg, a.v, a.pos, a.speed, b.v, b.pos, b.speed, tostring(ok), why))