public static List <Step> FindIntersections(double y, Polygon poly)
{
var result = new List <Step>();
for (int lineFromIndex = 0; lineFromIndex < poly.Vertices.Count; lineFromIndex++)
{
int lineToIndex = lineFromIndex + 1;
if (lineFromIndex == poly.Vertices.Count - 1)
{
lineToIndex = 0;
}
var fromPoint = poly.Vertices[lineFromIndex];
var toPoint = poly.Vertices[lineToIndex];
var intersectionWithThisLine = FillCalculator.FindIntersection(fromPoint, toPoint, y);
if (intersectionWithThisLine != null)
{
var step = new Step(Step.StepType.Stitch, intersectionWithThisLine);
result.Add(step);
}
}
List <Step> sortedByX = result
.Select(step => new KeyValuePair <Step, double>(step, step.Point.X))
.OrderBy(x => x.Value)
.Select <KeyValuePair <Step, double>, Step>(kvp => kvp.Key)
.ToList();
return(sortedByX);
}
public override List <Step> CalculateFillSteps()
{
FillCalculator fc = new FillCalculator(this.polygon, this.ct);
return(fc.Calculate());
}