/// <summary>
/// analyzes a node
/// </summary>
/// <param name="activeNode"> the active node </param>
/// <param name="index"> indicates the index of the item </param>
/// <param name="tolerance"> indicates the tolerance for badness </param>
/// <param name="lineProvider"> the line provider </param>
/// <returns> the next node </returns>
private LinkedListNode<Breakpoint> AnalyzeNode(
LinkedListNode<Breakpoint> activeNode,
int index,
double tolerance,
ILineProvider lineProvider)
{
Contract.Requires(activeNode != null);
Contract.Requires(index >= 0);
Contract.Requires(Check.IsFinite(tolerance));
Contract.Requires(tolerance >= 1.0);
Contract.Requires(lineProvider != null);
LinkedListNode<Breakpoint> nextNode = activeNode.Next;
int currentLine = activeNode.Value.Line;
LineItem indexItem = _Items[index];
double ratio = ComputeRatio(
ref indexItem, activeNode, currentLine, lineProvider);
if(ratio < -1.0 || indexItem.IsForcedBreak)
{
_Active.Remove(activeNode);
_LastDeactivated = activeNode.Value;
}
if(ratio >= -1.0 && ratio <= tolerance)
{
Demerits demerits = indexItem.ComputeDemerits(ratio / tolerance);
demerits =
indexItem.CombineFlaggedDemerits(
_Items[activeNode.Value.Position], demerits);
LineFitness fitness = LineFitness.FromLineRatio(ratio / tolerance);
if(fitness.MeasureFitnessGap(activeNode.Value.Fitness) > 1)
{
demerits += Demerits.FitnessPenalty;
}
demerits += activeNode.Value.Demerits;
if(demerits < _Candidates[fitness].Demerits)
{
double totalWidth;
double totalShrink;
double totalStretch;
ComputeSum(index, out totalWidth, out totalShrink, out totalStretch);
_Candidates[fitness] = new Breakpoint(
index,
currentLine + 1,
fitness,
totalWidth,
totalStretch,
totalShrink,
demerits,
ratio,
activeNode.Value);
_MinimumCandidate = Math.Min(_MinimumCandidate.Value, demerits.Value);
}
}
return nextNode;
}
/// <summary>
/// analyzes a breaking point
/// </summary>
/// <param name="index"> indicates the index of the breaking point </param>
/// <param name="tolerance"> indicates the tolerance for badness </param>
/// <param name="lineProvider"> the line provider </param>
private void AnalyzeBreakpoint(
int index, double tolerance, ILineProvider lineProvider)
{
Contract.Requires(index >= 0);
Contract.Requires(Check.IsFinite(tolerance));
Contract.Requires(tolerance >= 1.0);
Contract.Requires(lineProvider != null);
LinkedListNode<Breakpoint> activeNode = _Active.First;
while(activeNode != null)
{
_MinimumCandidate = Demerits.Infinity;
_Candidates[0] = Breakpoint.MaxDemerits;
_Candidates[1] = Breakpoint.MaxDemerits;
_Candidates[2] = Breakpoint.MaxDemerits;
_Candidates[3] = Breakpoint.MaxDemerits;
while(activeNode != null)
{
activeNode = AnalyzeNode(activeNode, index, tolerance, lineProvider);
}
if(_MinimumCandidate < Demerits.Infinity)
{
Demerits limit = _MinimumCandidate + Demerits.FitnessPenalty;
foreach(Breakpoint candidate in _Candidates)
{
if(candidate.Demerits <= limit)
{
_Active.AddLast(candidate);
}
}
}
}
}
