From f51eea6c0f0740ef2e9d21d5874609938e398577 Mon Sep 17 00:00:00 2001
From: Kirill <kirill.ivlev@gmail.com>
Date: Thu, 1 Oct 2026 20:30:53 +0300
Subject: [PATCH] Enhance simulation performance and accuracy by optimizing
 physical amount calculations and refining arithmetic operations

---
 stage/stage.gd                            | 15 +++-
 tests/README.md                           |  5 +-
 tests/test_exact_math.gd                  |  7 +-
 world/owniverse/README.md                 |  5 ++
 world/owniverse/automatic_production.gd   |  7 +-
 world/owniverse/civilization_evolution.gd |  4 +-
 world/owniverse/civilization_state.gd     | 39 +++++-----
 world/owniverse/evolution_coordinator.gd  |  5 +-
 world/owniverse/manual_production.gd      |  6 +-
 world/owniverse/math/README.md            |  5 ++
 world/owniverse/math/exact.gd             | 89 +++++++++++++++++------
 world/owniverse/object_batches.gd         | 11 +++
 world/owniverse/object_ledger.gd          |  7 ++
 world/owniverse/stellar_rules.gd          |  5 +-
 14 files changed, 155 insertions(+), 55 deletions(-)

diff --git a/stage/stage.gd b/stage/stage.gd
index 0db4d39..c685788 100644
--- a/stage/stage.gd
+++ b/stage/stage.gd
@@ -91,6 +91,8 @@ var g_counters: Dictionary[String, Counter] = {
 var g_active_items: Dictionary = {}
 
 var pending_page: int = -1
+var active_actions_dirty: bool = true
+var active_actions_elapsed: float = 0.0
 
 var owniverse:Owniverse = Owniverse.new()
 var owniverse_items: Dictionary[String, OwniverseItem] = {}
@@ -174,6 +176,7 @@ func _control_page(item: OwniverseItem) -> void:
         return
 
     g_active_items[item.item_page] = item
+    active_actions_dirty = true
 
     if current_item != null and current_item.item_page == item.item_page:
         current_item.set_selection(false)
@@ -338,6 +341,8 @@ func create_new_universe() -> void:
     description_samples.clear()
     description_rates.clear()
     description_elapsed = 0.0
+    active_actions_dirty = true
+    active_actions_elapsed = 0.0
     for label in g_item_descriptions:
         label.text = ""
     for item in owniverse_items.values():
@@ -379,8 +384,14 @@ func _process(delta: float) -> void:
 
     var actions = _check_counters(delta)
     _do_actions(actions)
-
-    _set_active_page_actions()
+    # Production limits are expensive (they walk the resource ledger). Refresh
+    # them when selection changes and at a modest cadence instead of every
+    # rendered frame. The simulation itself continues to run every frame.
+    active_actions_elapsed += delta
+    if active_actions_dirty or active_actions_elapsed >= 0.1:
+        active_actions_elapsed = 0.0
+        active_actions_dirty = false
+        _set_active_page_actions()
 
 
 func _change_speed(delta: int) -> void:
diff --git a/tests/README.md b/tests/README.md
index 2d1899f..4fdd216 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -13,8 +13,9 @@ godot --headless --path Owniverse.GI --script res://tests/benchmark_saved_state.
 
 На диагностической копии с 120 партиями прежняя рациональная арифметика после
 оптимизации пустых окон давала 90–99 мс на шаг 1/60 секунды на скорости 6.
-После перехода на целые блоки и float-остаток повторный замер дал 58–62 мс.
-При шаге 0,1 секунды: 71–82 мс вместо 117–138 мс. Это замеры расчёта на данной
+После перехода на целые блоки и устранения повторного построения физических
+количеств повторный замер дал 53–58 мс. При шаге 0,1 секунды: 65–67 мс вместо
+117–138 мс. Это замеры расчёта на данной
 копии, а не обещание FPS. Для сравнения старый JSON был преобразован только
 во временный тестовый файл; в загрузчик игры миграция не добавлена.
 Разреженные сценарии сравниваются с полным расчётом в `test_short_lived_events.gd`.
diff --git a/tests/test_exact_math.gd b/tests/test_exact_math.gd
index d2a6e0e..50c907b 100644
--- a/tests/test_exact_math.gd
+++ b/tests/test_exact_math.gd
@@ -62,11 +62,16 @@ func run():
     check(E.bounded(count), str(count), "integer counts never quantized")
     check(E.mul_div(E.of("1e27"), 15, 100), "150000000000000000000000000", "exact percentage")
     check(E.mul_div(count, count, count), str(count), "fused product beyond storage range")
+    var limit = E.of("1e27")
+    check(E.floor_value(E.mul_div(E.subtract(limit, 1), E.subtract(limit, 3), E.subtract(limit, 2))), "999999999999999999999999997", "fused ratio immediately below whole boundary")
+    check(E.floor_value(E.divide(E.MIN_INT, -3)), "3074457345618258602", "MIN_INT division preserves quotient")
+    check(E.floor_value(E.divide(-10, 3)), "-4", "native negative fractional division")
+    check(E.mul_div(E.MAX_INT, 0, 7), "0", "native zero fused product")
     check(E.subtract(E.add(count, 1), count), "1", "single unit at E27")
     check(E.floor_value(E.divide(E.subtract(count, 1), count)), "0", "division must not round up a whole object")
     check(E.fixed(E.add(count, E.of("0.125")), 3), "1000000000000000000000000001.125", "formatting without oversized intermediate")
     check(E.scientific(E.of("9.999999e27"), 2), "1.00E+28", "display rounding at upper boundary")
-    check(E.eq(E.power(10, -100), E.of("1e-100")), "true", "negative power needs no huge intermediate")
+    check(absf(E.approx(E.power(10, -100)) / E.approx(E.of("1e-100")) - 1.0) < 1e-15, "true", "negative power retains float precision without huge intermediate")
     var largest = E.of("9999999999999999999999999999")
     check(E.eq(E.decode(E.encode(largest)), largest), "true", "upper range round trip")
     check(E.valid_encoded(E.encode(largest)), "true", "upper range encoding valid")
diff --git a/world/owniverse/README.md b/world/owniverse/README.md
index 11d3cf7..2d10fe6 100644
--- a/world/owniverse/README.md
+++ b/world/owniverse/README.md
@@ -41,6 +41,11 @@ Stage обращается непосредственно к `world.presentation
 
 В `owniverse.gd` остались создание состояния и модулей, скорость и проверка входного delta перед запуском эволюции. Дублирующее поле new_state и закомментированная старая реализация удалены. Единственный источник текущего состояния — `world.state`.
 
+Внутри одной фазы снимок физических количеств переиспользуется для сверки
+этик, звёздного бюджета и бюджета структур. После списания партий или переходов
+создаётся новый снимок. Операции над одним типом объекта используют
+`physical_amount`, не пересчитывая полную карту вселенной.
+
 ### Порядок шага
 
 1. Определить обработанную десятую года. При продвижении времени восстановить недостающие партии жизни и проверить вместимость.
diff --git a/world/owniverse/automatic_production.gd b/world/owniverse/automatic_production.gd
index cf33d8d..afcbefe 100644
--- a/world/owniverse/automatic_production.gd
+++ b/world/owniverse/automatic_production.gd
@@ -216,7 +216,12 @@ func produce_newborn_lifetime(target: Dictionary, id: String, count: Variant, bo
         object_years = E.subtract(object_years, E.multiply(E.maximum(0, added), world.batches.expired_years(to_year, batch.start_year, batch.end_year)))
     object_years = E.maximum(0, object_years)
     for resource in products:
-        var output: Variant = E.multiply(E.multiply(object_years, products[resource]), WorldParameters.production(target, world.catalog.entities[id]))
+        var coefficient: Variant = E.multiply(products[resource], WorldParameters.production(target, world.catalog.entities[id]))
+        # A giant cohort can accumulate more than E27 object-years. Clamp the
+        # multiplicand before multiplying so the exact-number backend never
+        # constructs an out-of-range intermediate value.
+        var safe_years: Variant = (E.minimum(object_years, E.divide(E.max_value(), coefficient)) if E.gt(coefficient, 0) else 0)
+        var output: Variant = E.multiply(safe_years, coefficient)
         if E.contains(["H", "S"], resource):
             output = E.minimum(output, target.energy)
         var actual: Variant = world.ledger.credit(target, resource, output)
diff --git a/world/owniverse/civilization_evolution.gd b/world/owniverse/civilization_evolution.gd
index 6fc9977..e4d4d1b 100644
--- a/world/owniverse/civilization_evolution.gd
+++ b/world/owniverse/civilization_evolution.gd
@@ -76,8 +76,8 @@ static func consume_untriggered(world, target: Dictionary, plan: Dictionary, pop
         plan.to = E.maximum(plan.to, year)
     return removed
 
-static func prepare(world, target: Dictionary, expired: Dictionary, year: Variant, budget: Dictionary, rules: Dictionary) -> Dictionary:
-    State.reconcile(world, target, rules)
+static func prepare(world, target: Dictionary, expired: Dictionary, year: Variant, budget: Dictionary, rules: Dictionary, physical: Dictionary = {}) -> Dictionary:
+    State.reconcile(world, target, rules, physical)
     var remaining: Dictionary = target.ethics.duplicate(true)
     var plans: Dictionary = {}
     var colonies: Array = []
diff --git a/world/owniverse/civilization_state.gd b/world/owniverse/civilization_state.gd
index faa9c83..c08acb1 100644
--- a/world/owniverse/civilization_state.gd
+++ b/world/owniverse/civilization_state.gd
@@ -10,10 +10,11 @@ static func is_space_civilization(id: String, rules: Dictionary) -> bool:
 
 # Preserve any existing ethics. New populations start equally distributed;
 # reductions (including blasts) are proportional and never leave negative counts.
-static func reconcile(world, target: Dictionary, rules: Dictionary) -> void:
+static func reconcile(world, target: Dictionary, rules: Dictionary, physical: Dictionary = {}) -> void:
     if (not target.has("ethics")):
         target.ethics = {}
-    var physical: Dictionary = world.ledger.physical_amounts(target)
+    if physical.is_empty():
+        physical = world.ledger.physical_amounts(target)
     for id in rules:
         var count: Variant = physical.get(id, 0)
         var current: Dictionary = target.ethics.get(id, {})
@@ -40,8 +41,9 @@ static func detach_space_civilizations(target: Dictionary, rules: Dictionary) ->
 
 # A shared budget per stellar family, including stars bound into structures.
 # Reservations affect capacity, not the physical stock or its production.
-static func stellar_budget(world, target: Dictionary, rules: Dictionary) -> Dictionary:
-    var physical: Dictionary = world.ledger.physical_amounts(target)
+static func stellar_budget(world, target: Dictionary, rules: Dictionary, physical: Dictionary = {}) -> Dictionary:
+    if physical.is_empty():
+        physical = world.ledger.physical_amounts(target)
     var capacity: Dictionary = {}
     for id in physical:
         var entity = world.catalog.entities[id]
@@ -62,7 +64,7 @@ static func stellar_budget(world, target: Dictionary, rules: Dictionary) -> Dict
     var free: Dictionary = {}
     for home in capacity:
         free[home] = E.maximum(0, E.subtract(capacity[home], requested.get(home, 0)))
-    return {"capacity": capacity, "requested": requested, "free": free, "populations": populations, "habitats": habitat_budget(world, target, rules)}
+    return {"capacity": capacity, "requested": requested, "free": free, "populations": populations, "habitats": habitat_budget(world, target, rules, physical)}
 
 # Account for the source's existing reservation when changing stages. A failed
 # transition retains its population at the source, rather than losing objects.
@@ -105,8 +107,9 @@ static func admit_transition(budget: Dictionary, rules: Dictionary, source: Stri
 # advanced populations priority and lets a demotion cascade in the same cycle.
 static func enforce_capacity(world, target: Dictionary, rules: Dictionary, year: Variant) -> void:
     detach_space_civilizations(target, rules)
-    reconcile(world, target, rules)
-    var budget: Dictionary = stellar_budget(world, target, rules)
+    var physical: Dictionary = world.ledger.physical_amounts(target)
+    reconcile(world, target, rules, physical)
+    var budget: Dictionary = stellar_budget(world, target, rules, physical)
     var remaining: Dictionary = budget.capacity.duplicate()
     var remaining_homes: Dictionary = budget.habitats.capacity.duplicate()
     var stages: Array = []
@@ -141,10 +144,10 @@ static func enforce_capacity(world, target: Dictionary, rules: Dictionary, year:
             target.ethics[previous][ethic] = E.add(target.ethics[previous].get(ethic, 0), removed[ethic])
         if E.eq(previous, "C1.9"):
             var stars: Dictionary = {}
-            var physical: Dictionary = world.ledger.physical_amounts(target)
-            for star in physical:
-                if (E.eq(world.catalog.entities[star].event_group, "DwStar") and E.gt(physical[star], 0)):
-                    stars[star] = physical[star]
+            var current_physical: Dictionary = world.ledger.physical_amounts(target)
+            for star in current_physical:
+                if (E.eq(world.catalog.entities[star].event_group, "DwStar") and E.gt(current_physical[star], 0)):
+                    stars[star] = current_physical[star]
             var weights: Dictionary = QuantityMath.normalize_distribution(stars)
             # Worlds are aggregates: a star may host several inhabited planets.
             var assigned: Variant = 0
@@ -158,13 +161,15 @@ static func enforce_capacity(world, target: Dictionary, rules: Dictionary, year:
                     target.binds[owner] = {}
                 target.binds[owner][previous] = E.add(target.binds[owner].get(previous, 0), amount)
                 target.amount[previous] = E.subtract(target.amount[previous], amount)
-    reconcile(world, target, rules)
-    assign_homes(world, target, rules)
+    physical = world.ledger.physical_amounts(target)
+    reconcile(world, target, rules, physical)
+    assign_homes(world, target, rules, physical)
 
 # Unity's structure chain: direct Claim resets the required structure count;
 # intervening stages require ten times more units of the preceding structure.
-static func habitat_budget(world, target: Dictionary, rules: Dictionary) -> Dictionary:
-    var physical: Dictionary = world.ledger.physical_amounts(target)
+static func habitat_budget(world, target: Dictionary, rules: Dictionary, physical: Dictionary = {}) -> Dictionary:
+    if physical.is_empty():
+        physical = world.ledger.physical_amounts(target)
     var structures: Array = []
     var capacity: Dictionary = {}
     for id in world.catalog.entities:
@@ -198,8 +203,8 @@ static func habitat_budget(world, target: Dictionary, rules: Dictionary) -> Dict
         requested[req.id] = E.add(requested.get(req.id, 0), E.multiply(physical.get(id, 0), req.units))
     return {"capacity": capacity, "requested": requested, "requirements": requirements, "structures": structures, "anchors": anchors}
 
-static func assign_homes(world, target: Dictionary, rules: Dictionary) -> void:
-    var budget: Dictionary = habitat_budget(world, target, rules)
+static func assign_homes(world, target: Dictionary, rules: Dictionary, physical: Dictionary = {}) -> void:
+    var budget: Dictionary = habitat_budget(world, target, rules, physical)
     var used: Dictionary = {}
     target.civilization_homes = {}
     var stages: Array = budget.anchors.keys()
diff --git a/world/owniverse/evolution_coordinator.gd b/world/owniverse/evolution_coordinator.gd
index 2b87724..0f2f074 100644
--- a/world/owniverse/evolution_coordinator.gd
+++ b/world/owniverse/evolution_coordinator.gd
@@ -92,8 +92,9 @@ func evolve_batch_generation(target: Dictionary, to_year: Variant, completed: Di
         return false
     var fractions: Dictionary = {}
     var outputs: Dictionary = {}
-    var star_budget: Dictionary = CivilizationState.stellar_budget(world, target, Global.CivilizationRules)
-    var civilization_transaction: Dictionary = CivilizationEvolution.prepare(world, target, expired, to_year, star_budget, Global.CivilizationRules)
+    var current_quantities: Dictionary = world.ledger.physical_amounts(target)
+    var star_budget: Dictionary = CivilizationState.stellar_budget(world, target, Global.CivilizationRules, current_quantities)
+    var civilization_transaction: Dictionary = CivilizationEvolution.prepare(world, target, expired, to_year, star_budget, Global.CivilizationRules, current_quantities)
     for id in expired:
         var total: Variant = 0
         for part : Dictionary in expired[id]:
diff --git a/world/owniverse/manual_production.gd b/world/owniverse/manual_production.gd
index bd685b3..7a61b93 100644
--- a/world/owniverse/manual_production.gd
+++ b/world/owniverse/manual_production.gd
@@ -11,12 +11,14 @@ func try_production(target: Dictionary, entity: OwniverseEntity, amount: Variant
     trial.binds = target.binds.duplicate(true)
     trial.auto_resources = target.auto_resources.duplicate()
     trial.batches = target.batches.duplicate()
+    # Physical object totals do not change while resources are withdrawn from
+    # this transaction. Keep one snapshot instead of scanning every resource.
+    var physical: Dictionary = world.ledger.physical_amounts(trial)
     var copied_batches: Dictionary = {}
     for resource in entity.cost:
         var cost: Variant = E.round_value(E.multiply(E.maximum(0, entity.cost[resource]), amount))
         if (automatic and E.lt(trial.auto_resources.get(resource, 0), cost)):
             return false
-        var before: Dictionary = world.ledger.physical_amounts(trial)
         var taken: Dictionary = world.ledger.take_available(trial, resource, cost)
         var total: Variant = 0
         for quantity in taken.values():
@@ -30,7 +32,7 @@ func try_production(target: Dictionary, entity: OwniverseEntity, amount: Variant
             if (trial.batches.has(id) and (not copied_batches.has(id))):
                 trial.batches[id] = trial.batches[id].duplicate(true)
                 copied_batches[id] = true
-            var factor: Variant = (E.subtract(1, E.divide(taken[id], before[id])) if E.gt(before.get(id, 0), 0) else 0)
+            var factor: Variant = (E.subtract(1, E.divide(taken[id], physical[id])) if E.gt(physical.get(id, 0), 0) else 0)
             world.batches.scale_batches(trial, id, factor)
     if (not world.ledger.bind_new_owners(trial, {entity.id: amount}, true)):
         return false
diff --git a/world/owniverse/math/README.md b/world/owniverse/math/README.md
index ee7a4b9..2a84155 100644
--- a/world/owniverse/math/README.md
+++ b/world/owniverse/math/README.md
@@ -21,6 +21,11 @@ polarity × (high × 10^14 + low + fraction)
 ## Операции
 
 Сложение, вычитание и сравнение работают непосредственно с блоками.
+Деление int64 и объединённое умножение/деление при безопасном произведении
+используют нативную арифметику. Перевод больших целых между блоками и временными
+разрядами, извлечение коэффициента и сборка результата обходятся без строк.
+Дробный коэффициент нормализуется численно до 16 значащих цифр; последние биты
+float могут отличаться от результата прежнего строкового преобразования.
 Для умножения и деления `big_integer.gd` используется как временный вычислитель
 с безопасными разрядами по основанию 10^9. Результат сразу возвращается в
 фиксированную структуру. Размер временных дробей определяется входными float,
diff --git a/world/owniverse/math/exact.gd b/world/owniverse/math/exact.gd
index 5de7443..e1d8566 100644
--- a/world/owniverse/math/exact.gd
+++ b/world/owniverse/math/exact.gd
@@ -8,31 +8,55 @@ const MIN_INT: int = -9223372036854775807 - 1
 const BLOCK: int = 100000000000000 # 10^14
 const LIMIT: Array = [0, 0, 0, 10] # 10^28, exclusive
 
+static func max_value():
+    return make([999999999, 999999999, 9999])
+
 static func make(n: Array, d: Array = [1], polarity: int = 1):
     assert(d != [0], "Zero denominator")
+    if n.size() <= 2 and d.size() <= 2:
+        var numerator: int = n[0] + (n[1] * SMALL if n.size() == 2 else 0)
+        var denominator: int = d[0] + (d[1] * SMALL if d.size() == 2 else 0)
+        var whole: int = numerator / denominator
+        var fraction: float = minf(float(numerator % denominator) / float(denominator), 1.0 - pow(2.0, -53))
+        return _compose(whole / BLOCK, whole % BLOCK, fraction, polarity)
     var qr: Array = Big.divmod(n, d)
-    var fraction: float = 0.0
-    if qr[1] != [0]:
-        var numerator_text: String = Big.decimal(qr[1])
-        var denominator_text: String = Big.decimal(d)
-        if denominator_text.length() < 300:
-            fraction = float(numerator_text) / float(denominator_text)
-        else:
-            var exponent: int = maxi(0, numerator_text.length() - 16) - maxi(0, denominator_text.length() - 16)
-            fraction = float(numerator_text.left(16)) / float(denominator_text.left(16))
-            fraction *= pow(10.0, maxi(-308, exponent))
-            fraction *= pow(10.0, mini(0, exponent + 308))
-    # A remainder below one must not round up and create a whole object.
-    fraction = minf(fraction, 1.0 - pow(2.0, -53))
+    var fraction: float = _fraction_ratio(qr[1], d)
     return _from_whole(qr[0], fraction, polarity)
 
+static func _fraction_ratio(n: Array, d: Array) -> float:
+    if n == [0]: return 0.0
+    var numerator: float = 0.0
+    var denominator: float = 0.0
+    var n_start: int = maxi(0, n.size() - 3)
+    var d_start: int = maxi(0, d.size() - 3)
+    for i in range(n.size() - 1, n_start - 1, -1): numerator = numerator * SMALL + n[i]
+    for i in range(d.size() - 1, d_start - 1, -1): denominator = denominator * SMALL + d[i]
+    var exponent: int = 9 * (n_start - d_start)
+    var fraction: float = numerator / denominator * pow(10.0, maxi(-308, exponent))
+    fraction *= pow(10.0, mini(0, exponent + 308))
+    return minf(fraction, 1.0 - pow(2.0, -53))
+
 static func _from_whole(n: Array, fraction: float, polarity: int):
-    var text: String = Big.decimal(n)
     assert(Big.compare(n, LIMIT) < 0, "Number exceeds E27 range")
-    var high: int = int(text.left(text.length() - 14)) if text.length() > 14 else 0
-    var low: int = int(text.right(14))
+    var middle: int = n[1] if n.size() > 1 else 0
+    var low: int = n[0] + (middle % 100000) * SMALL
+    var high: int = middle / 100000
+    if n.size() > 2: high += n[2] * 10000
+    if n.size() > 3: high += n[3] * 10000000000000
     return _compose(high, low, fraction, polarity)
 
+static func _whole_limbs(high: int, low: int) -> Array:
+    return Big.trim([low % SMALL, low / SMALL + (high % 10000) * 100000,
+        (high / 10000) % SMALL, high / 10000000000000])
+
+static func _int_limbs(value: int) -> Array:
+    var result: Array = []
+    # Modulo/division before abs also supports MIN_INT.
+    while value != 0:
+        result.append(absi(value % SMALL))
+        value /= SMALL
+    return result if not result.is_empty() else [0]
+
 static func _compose(high: int, low: int, fraction: float, polarity: int):
     if fraction >= 1.0:
         low += int(floorf(fraction))
@@ -91,17 +115,23 @@ static func of(value):
 
 static func parts(value) -> Array:
     value = of(value)
-    if value is int: return [Big.parse(str(value).trim_prefix("-")), [1], -1 if value < 0 else 1]
-    var whole: Array = Big.parse(str(value.high) + "%014d" % value.low)
+    if value is int: return [_int_limbs(value), [1], -1 if value < 0 else 1]
+    var whole: Array = _whole_limbs(value.high, value.low)
     if value.fraction == 0.0: return [whole, [1], value.polarity]
     # Bound temporary decimal work to 16 significant digits of the float.
     # Normalize first so tiny rates retain their significant digits as well.
     var exponent: int = maxi(-323, int(floor(log(value.fraction) / log(10.0))))
-    var text: String = String.num(value.fraction / pow(10.0, exponent), 15)
-    var point: int = text.find(".")
-    if point >= 0: exponent -= text.length() - point - 1
-    var n: Array = Big.parse(text.replace(".", ""))
-    var d: Array = Big.parse("1" + "0".repeat(-exponent))
+    var mantissa: int = roundi((value.fraction / pow(10.0, exponent)) * 1000000000000000.0)
+    exponent -= 15
+    while mantissa % 10 == 0 and mantissa > 0:
+        mantissa /= 10
+        exponent += 1
+    var n: Array = _int_limbs(mantissa)
+    var d: Array = []
+    d.resize((-exponent) / 9 + 1)
+    d.fill(0)
+    const POWERS: Array = [1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000]
+    d[d.size() - 1] = POWERS[(-exponent) % 9]
     return [Big.add(Big.multiply(whole, d), n), d, value.polarity]
 
 static func numeric(value) -> bool:
@@ -208,6 +238,8 @@ static func multiply(a, b):
 ## Fused ratio: the temporary product is never stored as a simulation value.
 static func mul_div(a, b, divisor):
     if not finite(a) or not finite(b) or not finite(divisor): return of(approx(a) * approx(b) / approx(divisor))
+    if a is int and b is int and a != MIN_INT and b != MIN_INT:
+        if b == 0 or absi(a) <= MAX_INT / absi(b): return divide(a * b, divisor)
     var x: Array = parts(a)
     var y: Array = parts(b)
     var z: Array = parts(divisor)
@@ -220,7 +252,16 @@ static func divide(a, b):
     if eq(b, 1): return of(a)
     if a is int and b is int and b != 0 and not (a == MIN_INT and b == -1):
         if a % b == 0: return a / b
-    return mul_div(a, 1, b)
+        if a != MIN_INT and b != MIN_INT:
+            var numerator: int = absi(a)
+            var denominator: int = absi(b)
+            var whole: int = numerator / denominator
+            var fraction: float = minf(float(numerator % denominator) / float(denominator), 1.0 - pow(2.0, -53))
+            return _compose(whole / BLOCK, whole % BLOCK, fraction, -1 if (a < 0) != (b < 0) else 1)
+    var x: Array = parts(a)
+    var y: Array = parts(b)
+    assert(y[0] != [0], "Division by zero")
+    return make(Big.multiply(x[0], y[1]), Big.multiply(x[1], y[0]), x[2] * y[2])
 
 static func floor_value(a):
     if not finite(a) or a is int: return a
diff --git a/world/owniverse/object_batches.gd b/world/owniverse/object_batches.gd
index 36199af..8430c83 100644
--- a/world/owniverse/object_batches.gd
+++ b/world/owniverse/object_batches.gd
@@ -6,6 +6,17 @@ const WorldParameters = preload("res://world/owniverse/world_parameters.gd")
 
 func scale_batches(target: Dictionary, id: String, factor: Variant) -> void:
     var batches: Array = target.batches.get(id, [])
+    if batches.is_empty():
+        return
+    # The common case for short-lived stellar events is a single cohort. Avoid
+    # allocating the shares array and sorting it when no redistribution is
+    # needed.
+    if batches.size() == 1:
+        var only: Dictionary = batches[0]
+        var expected: Variant = E.multiply(only.amount, E.maximum(0, factor))
+        only.amount = E.round_value(expected)
+        only.withdraw_remainder = E.minimum(only.get("withdraw_remainder", 0), only.amount)
+        return
     var total: Variant = 0
     var assigned: Variant = 0
     var shares: Array = []
diff --git a/world/owniverse/object_ledger.gd b/world/owniverse/object_ledger.gd
index c80e51e..91b09c0 100644
--- a/world/owniverse/object_ledger.gd
+++ b/world/owniverse/object_ledger.gd
@@ -15,6 +15,13 @@ func physical_amounts(source: Dictionary) -> Dictionary:
     return amounts
 
 
+func physical_amount(source: Dictionary, id: String) -> Variant:
+    var amount: Variant = E.maximum(0, source.amount.get(id, 0))
+    for bindings: Dictionary in source.binds.values():
+        amount = E.add(amount, E.maximum(0, bindings.get(id, 0)))
+    return amount
+
+
 func available(source: Dictionary, id: String) -> Variant:
     var amount: Variant = 0
     for member in world.catalog.members(id):
diff --git a/world/owniverse/stellar_rules.gd b/world/owniverse/stellar_rules.gd
index 3d397ba..d611ba5 100644
--- a/world/owniverse/stellar_rules.gd
+++ b/world/owniverse/stellar_rules.gd
@@ -69,7 +69,6 @@ func destroy_planets(target: Dictionary, owner_id: String, ratio: Variant, level
     if (E.le(ratio, 0) or not E.contains([1, 2], level)):
         return
     var held: Dictionary = target.binds.get(owner_id, {})
-    var physical: Dictionary = world.ledger.physical_amounts(target)
     var rocky: Variant = 0
     for id in held.keys():
         if ((not world.catalog.entities.has(id)) or E.ne(world.catalog.entities[id].group_as, "Planet")):
@@ -82,8 +81,10 @@ func destroy_planets(target: Dictionary, owner_id: String, ratio: Variant, level
             target.destruction_remainders[key] = 0
         if E.le(destroyed, 0):
             continue
+        var physical: Variant = world.ledger.physical_amount(target, id)
         held[id] = E.subtract(held[id], destroyed)
-        world.batches.scale_batches(target, id, E.subtract(1, E.divide(destroyed, physical[id])))
+        if E.gt(physical, 0):
+            world.batches.scale_batches(target, id, E.subtract(1, E.divide(destroyed, physical)))
         if E.eq(level, 1):
             rocky = E.add(rocky, destroyed)
     if E.gt(rocky, 0):