private void AddBoundPairsToActiveEdges(float bottomY)
{
int i = m_localMinimaList.Count - 1;
while (i >= 0)
{
if (m_localMinimaList[i].MinimumCoordinate != bottomY)
break;
int boundPairIndex = m_usedBoundPairs.Count;
m_usedBoundPairs.Add(m_localMinimaList[i]);
var parentPoly = m_localMinimaList[i].Parent;
MyPolygon.Vertex minimumVertex, prevVertex, nextVertex;
parentPoly.GetVertex(m_localMinimaList[i].Minimum, out minimumVertex);
parentPoly.GetVertex(minimumVertex.Prev, out prevVertex);
parentPoly.GetVertex(minimumVertex.Next, out nextVertex);
Debug.Assert(minimumVertex.Coord.Y == bottomY);
PolygonType polyType = parentPoly == m_polyA ? PolygonType.SUBJECT : PolygonType.CLIP;
Edge leftEdge = PrepareActiveEdge(boundPairIndex, ref minimumVertex, ref nextVertex, polyType, Side.LEFT);
Edge rightEdge = PrepareActiveEdge(boundPairIndex, ref minimumVertex, ref prevVertex, polyType, Side.RIGHT);
int insertPosition = SortInMinimum(ref leftEdge, ref rightEdge, polyType);
if (leftEdge.Contributing)
{
Debug.Assert(rightEdge.Contributing, "Contributing status of minimum edges was not consistent!");
var newPoly = new PartialPolygon();
newPoly.Append(minimumVertex.Coord);
leftEdge.AssociatedPolygon = newPoly;
rightEdge.AssociatedPolygon = newPoly;
}
else
{
Debug.Assert(!rightEdge.Contributing, "Contributing status of minimum edges was not consistent!");
}
if (leftEdge.DXdy > rightEdge.DXdy)
{
/*leftEdge.OutputSide = Side.RIGHT;
rightEdge.OutputSide = Side.LEFT;*/
m_activeEdgeList.Insert(insertPosition, rightEdge);
m_activeEdgeList.Insert(insertPosition + 1, leftEdge);
}
else
{
Debug.Assert(leftEdge.DXdy < rightEdge.DXdy, "Overlapping edges in an input polygon!");
m_activeEdgeList.Insert(insertPosition, leftEdge);
m_activeEdgeList.Insert(insertPosition + 1, rightEdge);
}
--i;
}
int removeCount = m_localMinimaList.Count - 1 - i;
m_localMinimaList.RemoveRange(i + 1, removeCount);
}
private void PerformIntersection(int leftEdgeIndex, int rightEdgeIndex, ref Edge e1, ref Edge e2, ref Vector3 intersectionPosition, IntersectionClassification intersectionClassification)
{
Debug.Assert(intersectionClassification != IntersectionClassification.INVALID);
switch (intersectionClassification)
{
case IntersectionClassification.LIKE_INTERSECTION:
Debug.Assert((e1.Contributing && e2.Contributing) || (!e1.Contributing && !e2.Contributing));
Debug.Assert((e1.OutputSide == Side.LEFT && e2.OutputSide == Side.RIGHT) || (e1.OutputSide == Side.RIGHT && e2.OutputSide == Side.LEFT));
Side swapSide = e1.OutputSide;
e1.OutputSide = e2.OutputSide;
e2.OutputSide = swapSide;
if (e1.Contributing)
{
if (e1.OutputSide == Side.RIGHT)
{
e1.AssociatedPolygon.Append(intersectionPosition);
e2.AssociatedPolygon.Prepend(intersectionPosition);
}
else
{
e1.AssociatedPolygon.Prepend(intersectionPosition);
e2.AssociatedPolygon.Append(intersectionPosition);
}
}
break;
case IntersectionClassification.LEFT_E1_INTERMEDIATE:
e1.AssociatedPolygon.Append(intersectionPosition);
break;
case IntersectionClassification.RIGHT_E1_INTERMEDIATE:
e1.AssociatedPolygon.Prepend(intersectionPosition);
break;
case IntersectionClassification.LEFT_E2_INTERMEDIATE:
e2.AssociatedPolygon.Append(intersectionPosition);
break;
case IntersectionClassification.RIGHT_E2_INTERMEDIATE:
e2.AssociatedPolygon.Prepend(intersectionPosition);
break;
case IntersectionClassification.LOCAL_MINIMUM:
var newPoly = new PartialPolygon();
newPoly.Append(intersectionPosition);
e1.AssociatedPolygon = newPoly;
e2.AssociatedPolygon = newPoly;
break;
case IntersectionClassification.LOCAL_MAXIMUM:
AddLocalMaximum(leftEdgeIndex, rightEdgeIndex, ref e1, ref e2, intersectionPosition);
break;
}
PartialPolygon swap = e1.AssociatedPolygon;
e1.AssociatedPolygon = e2.AssociatedPolygon;
e2.AssociatedPolygon = swap;
if (intersectionClassification != IntersectionClassification.LIKE_INTERSECTION)
{
e1.Contributing = !e1.Contributing;
e2.Contributing = !e2.Contributing;
}
m_activeEdgeList[leftEdgeIndex] = e2;
m_activeEdgeList[rightEdgeIndex] = e1;
}
private Edge FindOtherPolygonEdge(PartialPolygon polygon, int thisEdgeIndex, out int otherEdgeIndex)
{
Debug.Assert(m_activeEdgeList.Where(edge => edge.AssociatedPolygon == polygon).Count() == 2);
for (int i = 0; i < m_activeEdgeList.Count; ++i)
{
if (i == thisEdgeIndex) continue;
if (m_activeEdgeList[i].AssociatedPolygon == polygon)
{
otherEdgeIndex = i;
return m_activeEdgeList[i];
}
}
Debug.Assert(false);
otherEdgeIndex = -1;
return default(Edge);
}
public void Add(PartialPolygon other)
{
if (other.m_vertices.Count == 0) return;
// Append the first vertex with the check and the rest without
Append(other.m_vertices[0]);
for (int i = 1; i < other.m_vertices.Count; ++i)
{
m_vertices.Add(other.m_vertices[i]);
}
}
