/// <summary>
/// Forces the fill winding of the points within the ring.
/// </summary>
/// <param name="desiredWinding">The desired winding order to specify a fill region.</param>
/// <remarks>
/// If the current <see cref="Vertesaur.Ring2.Hole"/> property of this ring is <c>null</c>
/// then the Hole property will be set if possible to the value corresponding to the given
/// fill point winding.
/// If the current <see cref="Vertesaur.Ring2.Hole"/> property of this ring is <c>true</c>
/// or <c>false</c> then the points will be ordered if possible in a way to match the given
/// fill point winding and hole property.
/// <list type="bullet">
/// <item><term>Example 1</term><description>
/// Hole is initially <c>null</c> and points are in CounterClockwise order.
/// If <paramref name="desiredWinding"/> is Clockwise then Hole will then be set to <c>true</c>
/// and the points will not be changed.
/// </description></item>
/// <item><term>Example 2</term><description>
/// Hole is <c>false</c> and points are in Clockwise order. If <paramref name="desiredWinding"/>
/// is CounterClockwise then the order of the points in the ring will be reversed.
/// </description></item>
/// </list>
/// </remarks>
public void ForceFillWinding(PointWinding desiredWinding)
{
if (PointWinding.Unknown == desiredWinding)
{
throw new ArgumentException("DesiredWinding may not be Unknown.", "desiredWinding");
}
Contract.EndContractBlock();
var currentWinding = DetermineWinding();
if (PointWinding.Unknown == currentWinding)
{
return;
}
if (_hole.HasValue)
{
if (
(currentWinding != desiredWinding && !_hole.Value)
||
(currentWinding == desiredWinding && _hole.Value)
)
{
_pointList.Reverse();
}
}
else
{
_hole = (currentWinding != desiredWinding);
}
}
public IntersectionResults Turtle(PointWinding fillWinding)
{
Contract.Ensures(Contract.Result <IntersectionResults>() != null);
// now that it is all sorted the turtle starts scooting around, making new rings:
//
// --== .-----. | ~ard
// --== / \ |
// A --== <_______(`~`) B | D E
// ---*---------//-----//------*-------------*---*---------*---
// C |
// |
//
// please wait while SPEED TURTLE!!! assembles your new rings
var rings = new Polygon2();
PolygonCrossing startEntrance;
while ((startEntrance = FindNextStartableEntrance()) != null)
{
var buildingRing = new List <Point2>();
var entrance = startEntrance;
do
{
var exit = TraverseBSide(entrance, buildingRing);
if (exit == null)
{
VisitEntrance(startEntrance); // may need to do this to be safe
break; // unmatched entrance
}
VisitExit(exit);
entrance = TraverseASide(exit, buildingRing);
if (entrance == null)
{
break; // unmatched exit
}
VisitEntrance(entrance);
} while (entrance != startEntrance);
if (buildingRing.Count >= 3)
{
rings.Add(new Ring2(buildingRing)); // here is a new ring
}
}
if (fillWinding != PointWinding.Unknown)
{
rings.ForceFillWinding(fillWinding);
}
return(BuildFinalResults(rings));
}
/// <summary>
/// Forces the fill winding of the points within all contained rings to be uniform.
/// </summary>
/// <param name="desiredWinding">The desired winding order that defines a fill ring.</param>
/// <seealso cref="Vertesaur.Ring2.ForceFillWinding"/>
public void ForceFillWinding(PointWinding desiredWinding)
{
if (PointWinding.Unknown == desiredWinding)
{
throw new ArgumentException("desiredWinding may not be Unknown", "desiredWinding");
}
Contract.EndContractBlock();
foreach (var ring in this)
{
Contract.Assume(ring != null);
ring.ForceFillWinding(desiredWinding);
}
}
public IntersectionResults Turtle(PointWinding fillWinding) {
Contract.Ensures(Contract.Result<IntersectionResults>() != null);
// now that it is all sorted the turtle starts scooting around, making new rings:
//
// --== .-----. | ~ard
// --== / \ |
// A --== <_______(`~`) B | D E
// ---*---------//-----//------*-------------*---*---------*---
// C |
// |
//
// please wait while SPEED TURTLE!!! assembles your new rings
var rings = new Polygon2();
PolygonCrossing startEntrance;
while ((startEntrance = FindNextStartableEntrance()) != null) {
var buildingRing = new List<Point2>();
var entrance = startEntrance;
do {
var exit = TraverseBSide(entrance, buildingRing);
if (exit == null) {
VisitEntrance(startEntrance); // may need to do this to be safe
break; // unmatched entrance
}
VisitExit(exit);
entrance = TraverseASide(exit, buildingRing);
if (entrance == null) {
break; // unmatched exit
}
VisitEntrance(entrance);
} while (entrance != startEntrance);
if (buildingRing.Count >= 3)
rings.Add(new Ring2(buildingRing)); // here is a new ring
}
if (fillWinding != PointWinding.Unknown)
rings.ForceFillWinding(fillWinding);
return BuildFinalResults(rings);
}
