internal static bool EdgeIsPierced(CdtEdge e, Point source, Point target, CdtTriangle cdtTriangle)
{
var area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, source, target);
var area1 = Point.SignedDoubledTriangleArea(e.lowerSite.Point, source, target);
if (ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) > 0)
{
return(false);
}
area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, source);
area1 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, target);
if (ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) > 0)
{
return(false);
}
var otherT = e.GetOtherTriangle(cdtTriangle);
if (otherT == null)
{
return(true);
}
var otherSite = otherT.OppositeSite(e);
area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, otherSite.Point);
return(ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) >= 0);
}
static CdtEdge FindNextEdgeOnPerimeter(CdtEdge e)
{
var t = e.CwTriangle ?? e.CcwTriangle;
e = t.Edges[t.Edges.Index(e) + 2];
while (e.CwTriangle != null && e.CcwTriangle != null)
{
t = e.GetOtherTriangle(t);
e = t.Edges[t.Edges.Index(e) + 2];
}
return(e);
}
bool FindNextPierced(Point start, Point end, ref CdtTriangle t, ref CdtEdge piercedEdge)
{
t = piercedEdge.GetOtherTriangle(t);
if (t == null)
{
return(false);
}
var i = t.Edges.Index(piercedEdge);
for (int j = i + 1; j <= i + 2; j++)
{
var pe = t.Edges[j];
piercedEdge = PiercedEdgeQuery(pe, start, end, t);
if (piercedEdge != null)
{
// CdtSweeper.ShowFront(trs, null,
// new []{new LineSegment(e.SourcePoint,e.TargetPoint)}, new []{new LineSegment(pe.upperSite.Point,pe.lowerSite.Point)});
break;
}
}
return(!PointIsInsideOfTriangle(end, t));
}
internal static bool EdgeIsPierced(CdtEdge e, Point source, Point target, CdtTriangle cdtTriangle) {
var area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, source, target);
var area1 = Point.SignedDoubledTriangleArea(e.lowerSite.Point, source, target);
if (ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) > 0)
return false;
area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, source);
area1 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, target);
if (ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) > 0)
return false;
var otherT = e.GetOtherTriangle(cdtTriangle);
if (otherT == null)
return true;
var otherSite = otherT.OppositeSite(e);
area0 = Point.SignedDoubledTriangleArea(e.upperSite.Point, e.lowerSite.Point, otherSite.Point);
return (ApproximateComparer.Sign(area0) * ApproximateComparer.Sign(area1) >= 0);
}
bool FindNextPierced(Point start, Point end, ref CdtTriangle t, ref CdtEdge piercedEdge) {
t = piercedEdge.GetOtherTriangle(t);
if (t == null)
return false;
var i = t.Edges.Index(piercedEdge);
for (int j = i + 1; j <= i + 2; j++) {
var pe = t.Edges[j];
piercedEdge = PiercedEdgeQuery(pe, start, end, t);
if (piercedEdge != null) {
// CdtSweeper.ShowFront(trs, null,
// new []{new LineSegment(e.SourcePoint,e.TargetPoint)}, new []{new LineSegment(pe.upperSite.Point,pe.lowerSite.Point)});
break;
}
}
return !PointIsInsideOfTriangle(end, t);
}
internal void FindNextPierced()
{
Debug.Assert(negativeSign < positiveSign);
/*List<DebugCurve> l = null;
* if (db) {
* l = new List<DebugCurve>();
* l.Add(new DebugCurve(0.05, "red", new LineSegment(start, end)));
* l.Add(new DebugCurve(0.05, "blue", new LineSegment(piercedEdge.upperSite.Point, piercedEdge.lowerSite.Point)));
* l.Add(new DebugCurve(new Ellipse(3, 3, end)));
*
* var ii = currentTriangle.Edges.Index(piercedEdge);
* for (int j = ii + 1; j <= ii + 2; j++)
* l.Add(new DebugCurve(0.05, "brown", new LineSegment(currentTriangle.Edges[j].upperSite.Point, currentTriangle.Edges[j].lowerSite.Point)));
* }*/
currentTriangle = currentPiercedEdge.GetOtherTriangle(currentTriangle);
// ShowDebug(null,currentPiercedEdge,currentTriangle);
/* if (db) {
* for (int j = 0; j <= 2; j++) {
* var piercedEdge = currentTriangle.Edges[j];
* if (piercedEdge == piercedEdge) continue;
* l.Add(new DebugCurve(0.05, new LineSegment(piercedEdge.upperSite.Point, piercedEdge.lowerSite.Point)));
* }
*
* LayoutAlgorithmSettings.ShowDebugCurvesEnumeration(l.ToArray());
* }*/
if (currentTriangle == null)
{
currentPiercedEdge = null;
return;
}
var i = currentTriangle.Edges.Index(currentPiercedEdge);
int j; //pierced index
var oppositeSite = currentTriangle.Sites[i + 2];
var oppositeSiteSign = GetHyperplaneSign(oppositeSite);
if (negativeSign == 0)
{
Debug.Assert(positiveSign == 1);
if (oppositeSiteSign == -1 || oppositeSiteSign == 0)
{
negativeSign = oppositeSiteSign;
j = i + 1;
}
else
{
j = i + 2;
}
}
else if (positiveSign == 0)
{
Debug.Assert(negativeSign == -1);
if (oppositeSiteSign == 1 || oppositeSiteSign == 0)
{
positiveSign = oppositeSiteSign;
j = i + 2;
}
else
{
j = i + 1;
}
}
else if (oppositeSiteSign != positiveSign)
{
negativeSign = oppositeSiteSign;
j = i + 1;
}
else
{
Debug.Assert(negativeSign != oppositeSiteSign);
positiveSign = oppositeSiteSign;
j = i + 2;
}
currentPiercedEdge =
Point.SignedDoubledTriangleArea(end, currentTriangle.Sites[j].Point, currentTriangle.Sites[j + 1].Point) <
-ApproximateComparer.DistanceEpsilon
? currentTriangle.Edges[j]
: null;
// ShowDebug(null,currentPiercedEdge, currentTriangle);
}
static CdtEdge FindNextEdgeOnPerimeter(CdtEdge e) {
var t = e.CwTriangle ?? e.CcwTriangle;
e = t.Edges[t.Edges.Index(e) + 2];
while(e.CwTriangle != null && e.CcwTriangle != null) {
t = e.GetOtherTriangle(t);
e = t.Edges[t.Edges.Index(e) + 2];
}
return e;
}
