ludic.physics, ludic.character, ludic.vehicles: fact records reused, and phys_sink allocates nothing

The per-frame sweep over physics, character, vehicles and nav found three fact makers that made a record per fact: contacts and splashes, the character's and the vehicles'. Each keeps a pool now, as wildlife's and npc's do (q_unheld). phys_sink, asked on every removal, built two new lists each time; it filters into a kept spare pair and swaps. ludic.nav's paths and crowds already allocate nothing, and none of the four builds a string per call. What remains at load, reset or a world swap is not per frame. vehicle_feed takes its state mut. vehicles_test: 1000 fed facts, drained turn by turn, use at most 4 records. All packages 421.

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

packages/ludic.vehicles/keep.ludic

@@ -4,7 +4,7 @@
 export function vehicle_own(v: Vehicle) -> void { if v != null { v.owned = true } }
 
 # hay for a horse, up to a full belly
-export function vehicle_feed(vehicles_st: VehiclesState, v: Vehicle, amount: float) -> void {
+export function vehicle_feed(vehicles_st: mut VehiclesState, v: Vehicle, amount: float) -> void {
   if v == null { return }
   v.food = Math.min(v.food + amount, 100.0)
   ve_say(vehicles_st, VEHICLE_FED, v, amount)

packages/ludic.vehicles/ports.ludic

@@ -63,6 +63,9 @@ export state VehiclesState {
   ve_ly: float = 0.0
   ve_lz: float = 0.0
   ve_fact_q: Queue<VehicleFact> = ve_fact_q__new()
+  ve_fpool: []VehicleFact = new []VehicleFact   # every fact record made, reused once no drain holds it
+  ve_ffree: []VehicleFact = new []VehicleFact
+  ve_fnext: int = 0
 }
 function ve__dry(x: float, z: float) -> float { return -10000.0 }
 function ve__calm(x: float, z: float, fx: float, fz: float) -> float { return 0.0 }

packages/ludic.vehicles/state.ludic

@@ -6,8 +6,26 @@ export function vehicle_facts(vehicles_st: VehiclesState) -> Queue<VehicleFact>
   return vehicles_st.ve_fact_q
 }
 
-function ve_say(vehicles_st: VehiclesState, what: int, v: Vehicle, n: float) -> void {
+# a fact record no drain holds any more, made fresh (and kept) only when every one is held: a
+# fact can come every frame, and a record a frame is never given back
+function ve_fact_record(vehicles_st: mut VehiclesState) -> VehicleFact {
+  if vehicles_st.ve_fnext >= len(vehicles_st.ve_ffree) {
+    q_unheld(vehicle_facts(vehicles_st), vehicles_st.ve_fpool, vehicles_st.ve_ffree)
+    vehicles_st.ve_fnext = 0
+  }
+  if vehicles_st.ve_fnext < len(vehicles_st.ve_ffree) {
+    let f = vehicles_st.ve_ffree[vehicles_st.ve_fnext]
+    vehicles_st.ve_fnext += 1
+    return f
+  }
   let f = new VehicleFact
+  push(vehicles_st.ve_fpool, f)
+  return f
+}
+# how many fact records have ever been made: the peak held at once, not the facts pushed
+export function vehicle_fact_records(vehicles_st: VehiclesState) -> int { return len(vehicles_st.ve_fpool) }
+function ve_say(vehicles_st: mut VehiclesState, what: int, v: Vehicle, n: float) -> void {
+  let f = ve_fact_record(vehicles_st)
   f.what = what
   f.nid = v.nid
   f.kind = v.kind

packages/ludic.vehicles/tests/vehicles_test.ludic

@@ -375,4 +375,17 @@ program VehiclesTest {
     expect_eq(len(vehicles_all(vehicles_st)), 0)
     expect(vehicle_by_nid(vehicles_st, b.nid) == null)
   }
+
+  test "a fed fact a turn, drained each turn, makes a few records and then reuses them" (vehicles_st: mut VehiclesState, vehicles_test_st: mut VehiclesTestState) {
+    fresh(vehicles_st, vehicles_test_st)
+    vehicle_call_for(vehicles_st, 0, VEHICLE_HORSE, 0)
+    let h = vehicle_find(vehicles_st, VEHICLE_HORSE)
+    var fed = 0
+    for k in 0 .. 1000 {
+      vehicle_feed(vehicles_st, h, 1.0)
+      fed += count(facts(vehicles_st), VEHICLE_FED)
+    }
+    expect_eq(fed, 1000)
+    expect(vehicle_fact_records(vehicles_st) <= 4)
+  }
 }