/// <summary>
/// Initializes a new instance of the <see cref="DiceModifier"/> class.
/// </summary>
/// <param name="die">The die being modified.</param>
/// <param name="modifierValue">The value of the modification.</param>
/// <param name="rng">The random number generator.</param>
public DiceModifier(IAbstractDie die, int modifierValue, IRandomNumberGenerator rng)
: base(rng)
{
Debug.Assert(die != null, "The die cannot be null.");
this.die = die;
Modifier = modifierValue;
ProbabilityDistribution = CreateProbabilityDistribution(die, modifierValue);
}
private double CreateProbabilityDistribution(IAbstractDie die, ComparisonType comparisonType, int referenceValue)
{
Func <int, bool> comparitor = GetComparitor(comparisonType, referenceValue);
double result = die.ProbabilityDistribution.Specification
.Where(p => comparitor(p.Value))
.Sum(p => p.Probability);
Debug.Assert(0.0 <= result && result <= 1.0, "The probability should be in range [0.0, 1.0].");
return(result);
}
/// <summary>
/// Initializes a new instance of the <see cref="ThresholdCompare"/> class.
/// </summary>
/// <param name="die">The die whose result should be compared.</param>
/// <param name="comparisonType">How the result of <paramref name="die"/> should be compared.</param>
/// <param name="referenceValue">To what value <paramref name="die"/> should be compared.</param>
/// <param name="rng">The random number generator.</param>
public ThresholdCompare(IAbstractDie die, ComparisonType comparisonType, int referenceValue, IRandomNumberGenerator rng)
{
Debug.Assert(die != null, "The die cannot be null.");
Debug.Assert(
comparisonType == ComparisonType.Greater || comparisonType == ComparisonType.GreaterOrEqual ||
comparisonType == ComparisonType.Smaller || comparisonType == ComparisonType.SmallerOrEqual,
"The comparison type must be a known member.");
Debug.Assert(rng != null, "The random number generator cannot be null.");
this.die = die;
ComparisonType = comparisonType;
ReferenceValue = referenceValue;
this.rng = rng;
double successProbability = CreateProbabilityDistribution(die, comparisonType, referenceValue);
ProbabilityDistribution = new BooleanProbabilityDistribution(successProbability);
Debug.Assert(ProbabilityDistribution != null, "The property ProbabilityDistribution should be initialized.");
}
private DiscreteValueProbabilityDistribution CreateProbabilityDistribution(IAbstractDie die, int modifier)
{
return(new DiscreteValueProbabilityDistribution(die.ProbabilityDistribution.Specification
.Select(p => new ValueProbabilityPair(p.Value + modifier, p.Probability))));
}
