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.character/ports.ludic

@@ -104,6 +104,9 @@ export state CharacterState {
   chr_safe_x: float = 0.0
   chr_safe_z: float = 0.0
   chr_fact_q: Queue<CharacterFact> = chr_fact_q__new()
+  chr_fpool: []CharacterFact = new []CharacterFact   # every fact record made, reused once no drain holds it
+  chr_ffree: []CharacterFact = new []CharacterFact
+  chr_fnext: int = 0
 }
 function chr__top_plain(x: float, z: float, r: float, from_y: float, step: float, base: float) -> float { return base }
 function chr__bed_plain(x: float, z: float) -> float { return CharacterGround.height(x, z) }

packages/ludic.character/state.ludic

@@ -13,8 +13,24 @@ export function char_facts(character_st: CharacterState) -> Queue<CharacterFact>
   return character_st.chr_fact_q
 }
 
-function chr_say(character_st: CharacterState, what: int, v: 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 chr_fact_record(character_st: mut CharacterState) -> CharacterFact {
+  if character_st.chr_fnext >= len(character_st.chr_ffree) {
+    q_unheld(char_facts(character_st), character_st.chr_fpool, character_st.chr_ffree)
+    character_st.chr_fnext = 0
+  }
+  if character_st.chr_fnext < len(character_st.chr_ffree) {
+    let f = character_st.chr_ffree[character_st.chr_fnext]
+    character_st.chr_fnext += 1
+    return f
+  }
   let f = new CharacterFact
+  push(character_st.chr_fpool, f)
+  return f
+}
+function chr_say(character_st: mut CharacterState, what: int, v: float) -> void {
+  let f = chr_fact_record(character_st)
   f.what = what
   f.x = character_st.chr_x
   f.y = character_st.chr_y

packages/ludic.physics/shapes.ludic

@@ -32,8 +32,8 @@ export function phys_close(physics_st: mut PhysicsState) -> void {
     }
   }
   physics_st.ph_shapes = new []pointer
-  physics_st.ph_floats = new []int
-  physics_st.ph_float_k = new []float
+  List.clear(physics_st.ph_floats)
+  List.clear(physics_st.ph_float_k)
   if physics_st.ph_facts != null { q_clear(physics_st.ph_facts) }
 }
 

packages/ludic.physics/state.ludic

@@ -46,12 +46,17 @@ export state PhysicsState {
   ph_hard: float = 2.0            # metres a second: a contact under this is not a fact
   ph_floats: []int = new []int         # buoyant bodies' ids
   ph_float_k: []float = new []float      # and theirs: buoyancy, linear drag, angular drag, wet
+  ph_floats2: []int = new []int        # the spare pair phys_sink filters into
+  ph_float_k2: []float = new []float
   ph_rx: float = 0.0               # where the last phys_resolve put a body
   ph_rz: float = 0.0
   ph_walkers: []pointer = new []pointer   # a walker id is its place here; null once removed
   ph_ids: []int = words(PH_CAP * 2)
   ph_vals: []float = floats(PH_CAP * 4)
   ph_facts: Queue<PhysFact> = ph_facts__new()
+  ph_fpool: []PhysFact = new []PhysFact   # every fact record made, reused once no drain holds it
+  ph_ffree: []PhysFact = new []PhysFact
+  ph_fnext: int = 0
 }
 
 # the facts, oldest first

packages/ludic.physics/system.ludic

@@ -33,12 +33,28 @@ export function phys_steps(physics_st: PhysicsState) -> int { return physics_st.
 # m/s2 down is negative
 export function phys_gravity(physics_st: mut PhysicsState, y: float) -> void { if physics_st.ph_world != null { jph_world_gravity(physics_st.ph_world, y) } }
 
+# 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 ph_fact_record(physics_st: mut PhysicsState) -> PhysFact {
+  if physics_st.ph_fnext >= len(physics_st.ph_ffree) {
+    q_unheld(phys_facts(physics_st), physics_st.ph_fpool, physics_st.ph_ffree)
+    physics_st.ph_fnext = 0
+  }
+  if physics_st.ph_fnext < len(physics_st.ph_ffree) {
+    let f = physics_st.ph_ffree[physics_st.ph_fnext]
+    physics_st.ph_fnext += 1
+    return f
+  }
+  let f = new PhysFact
+  push(physics_st.ph_fpool, f)
+  return f
+}
 function ph_contacts(physics_st: mut PhysicsState) -> void {
   let n = jph_contacts_drain(physics_st.ph_world, physics_st.ph_ids, physics_st.ph_vals, PH_CAP)
   for i in 0 .. n {
     let speed = physics_st.ph_vals[i * 4 + 3]
     if speed >= physics_st.ph_hard {
-      let f = new PhysFact
+      let f = ph_fact_record(physics_st)
       f.what = PHYS_HIT
       f.a = physics_st.ph_ids[i * 2]
       f.b = physics_st.ph_ids[i * 2 + 1]

packages/ludic.physics/water.ludic

@@ -13,17 +13,22 @@ export function phys_float(physics_st: mut PhysicsState, id: int, buoyancy: floa
   push(physics_st.ph_float_k, 0.0)
 }
 
-# no longer floats (it is still a body)
+# no longer floats (it is still a body); every removal asks, so the lists are filtered into a kept
+# spare pair and swapped, never made anew
 export function phys_sink(physics_st: mut PhysicsState, id: int) -> void {
   if physics_st.ph_floats == null { return }
-  let ids = new []int
-  let ks = new []float
+  let ids = physics_st.ph_floats2
+  let ks = physics_st.ph_float_k2
+  List.clear(ids)
+  List.clear(ks)
   for i in 0 .. len(physics_st.ph_floats) {
     if physics_st.ph_floats[i] != id {
       push(ids, physics_st.ph_floats[i])
       for k in 0 .. PH_K { push(ks, physics_st.ph_float_k[i * PH_K + k]) }
     }
   }
+  physics_st.ph_floats2 = physics_st.ph_floats
+  physics_st.ph_float_k2 = physics_st.ph_float_k
   physics_st.ph_floats = ids
   physics_st.ph_float_k = ks
 }
@@ -56,10 +61,12 @@ function ph_buoy_one(physics_st: mut PhysicsState, i: int, id: int, x: float, z:
   physics_st.ph_float_k[k + 3] = float(wet)
 }
 
-function ph_splash(physics_st: PhysicsState, id: int, x: float, y: float, z: float) -> void {
-  let f = new PhysFact
+function ph_splash(physics_st: mut PhysicsState, id: int, x: float, y: float, z: float) -> void {
+  let f = ph_fact_record(physics_st)
   f.what = PHYS_SPLASH
   f.a = id
+  f.b = -1
+  f.speed = 0.0
   f.x = x;  f.y = y;  f.z = z
   q_push(phys_facts(physics_st), f)
 }

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)
+  }
 }