feat: add deterministic regional scheduler

2026-08-12 20:50:44 +02:00
parent 809e7c008d
commit d5eb2b81f9
10 changed files with 911 additions and 0 deletions
@@ -0,0 +1,69 @@
+class_name KeyedRandom
+extends RefCounted
+
+const MASK_32 := 0xFFFFFFFF
+const UINT32_RANGE := 4294967296.0
+
+
+static func value_u32(
+	world_seed: int, system_id: StringName, entity_id: StringName, occurrence: int
+) -> int:
+	var hash_value := int(world_seed) & MASK_32
+	hash_value = _mix_u32(hash_value ^ 0x9E3779B9)
+	for byte in String(system_id).to_utf8_buffer():
+		hash_value = _mix_u32(hash_value ^ int(byte))
+	hash_value = _mix_u32(hash_value ^ 0x85EBCA6B)
+	for byte in String(entity_id).to_utf8_buffer():
+		hash_value = _mix_u32(hash_value ^ int(byte))
+	hash_value = _mix_u32(hash_value ^ (occurrence & MASK_32))
+	return hash_value
+
+
+static func value_float(
+	world_seed: int, system_id: StringName, entity_id: StringName, occurrence: int
+) -> float:
+	return float(value_u32(world_seed, system_id, entity_id, occurrence)) / UINT32_RANGE
+
+
+static func range_int(
+	world_seed: int,
+	system_id: StringName,
+	entity_id: StringName,
+	occurrence: int,
+	minimum: int,
+	maximum: int
+) -> int:
+	if maximum < minimum:
+		return minimum
+	var width := maximum - minimum + 1
+	return minimum + value_u32(world_seed, system_id, entity_id, occurrence) % width
+
+
+static func range_float(
+	world_seed: int,
+	system_id: StringName,
+	entity_id: StringName,
+	occurrence: int,
+	minimum: float,
+	maximum: float
+) -> float:
+	if maximum <= minimum:
+		return minimum
+	return lerpf(minimum, maximum, value_float(world_seed, system_id, entity_id, occurrence))
+
+
+static func chance(
+	world_seed: int,
+	system_id: StringName,
+	entity_id: StringName,
+	occurrence: int,
+	probability: float
+) -> bool:
+	return value_float(world_seed, system_id, entity_id, occurrence) < clampf(probability, 0.0, 1.0)
+
+
+static func _mix_u32(value: int) -> int:
+	var mixed := value & MASK_32
+	mixed = ((mixed ^ (mixed >> 16)) * 0x7FEB352D) & MASK_32
+	mixed = ((mixed ^ (mixed >> 15)) * 0x846CA68B) & MASK_32
+	return (mixed ^ (mixed >> 16)) & MASK_32