Enum RepeatPreventionMode

Specifies how ProbabilityList<T> handles repeated consecutive selections of the same entry.

Namespace: Scylla.Core.Util.Random

Assembly: ScyllaCore.dll

Syntax

public enum RepeatPreventionMode

Remarks

Each mode represents a different trade-off between distribution accuracy, implementation cost, and the strength of the repeat-avoidance guarantee:

• Off - no overhead; highest variance.
• Spread - one extra linear scan on repeat; distribution is slightly biased because the repeated entry's probability is zeroed.
• Repick - bounded retries; distribution stays correct but retries add variable cost proportional to the entry's probability.
• Shuffle - O(n) deck build amortized over many picks; perfect distribution over full cycles, no history required during play.

Changing RepeatPrevention at runtime resets all shuffle state, so the next pick will deal from a freshly built deck if Shuffle is selected.

Fields

Name	Description
Off	Disables repeat prevention entirely. The same entry may be selected on consecutive picks according to its natural probability. Requires no history tracking and adds no overhead to the selection path.
Repick	Discards and re-samples when the same entry is picked consecutively, retrying up to min(activeCount * 3, 100) times before accepting the repeat as a last resort. This avoids infinite loops when all probability mass is concentrated on one entry.
Shuffle	Pre-shuffles a weighted deck of all active entries and deals from it sequentially. When the deck is exhausted, a new deck is built and shuffled. The number of passes through the same shuffled deck before reshuffling is controlled by ShuffleIterations.
Spread	Prevents an immediate repeat by zeroing the most recently picked entry's probability and re-sampling from the remaining entries when a repeat is detected. The remaining entries are sampled proportionally so their relative weights are preserved.