private void FinishLine(JCVEdge e)
{
if (!clipper.ClipEdge(e))
{
return;
}
// Make sure the graph edges are CCW
int flip = TriIsCCW(e.Sites[0].center, e.Points[0], e.Points[1]) ? 0 : 1;
for (int i = 0; i < 2; i++)
{
PointF[] tempPts = new PointF[2];
JCVSite home = e.Sites[i];
JCVSite neighbor = e.Sites[1 - i];
tempPts[flip] = e.Points[i];
tempPts[1 - flip] = e.Points[1 - i];
JCVGraphEdge ge = new JCVGraphEdge(e, home, neighbor, tempPts);
home.edges.Add(ge);
}
// // check that we didn't accidentally add a duplicate (rare), then remove it
// if(ge->next && ge->angle == ge->next->angle )
// {
// if(jcv_point_eq( &ge->pos[0], &ge->next->pos[0] ) && jcv_point_eq( &ge->pos[1], &ge->next->pos[1] ) )
// {
// ge->next = ge->next->next; // Throw it away, they're so few anyways
// }
// }
// }
}
private void SiteEvent(JCVSite site)
{
JCVHalfEdge left = GetEdgeAboveX(site.center);
JCVHalfEdge right = left.right;
JCVSite bottom = (left.Edge is null) ? sites[0] : left.rSite;
JCVEdge edge = new JCVEdge(bottom, site);
edges.Add(edge);
JCVHalfEdge he1 = new JCVHalfEdge(edge, false, left);
JCVHalfEdge he2 = new JCVHalfEdge(edge, true, he1);
lastInserted = right;
PointF p;
if (CheckCircleEvent(left, he1, out p))
{
priorityQueue.Remove(left);
left.vertex = p;
left.Y = p.Y + PointDistance(site.center, p);
priorityQueue.Add(left);
}
if (CheckCircleEvent(he2, right, out p))
{
he2.vertex = p;
he2.Y = p.Y + PointDistance(site.center, p);
priorityQueue.Add(he2);
}
}
public float A, B, C; // line equation: ax + by + c = 0
public JCVEdge(JCVSite site, PointF[] points)
{
Points = points;
Sites = new JCVSite[2];
Next = null;
Sites[0] = site;
Sites[1] = null;
}
public JCVGraphEdge(JCVEdge e, JCVSite home, JCVSite neighbor, PointF[] points)
{
Edge = e;
Home = home;
Neighbor = neighbor;
Points = points;
Angle = calcAngle(home);
}
//note to self: this is currently a black box. Figure out how it works at some point
private bool RightOf(JCVHalfEdge he, PointF p)
{
JCVEdge edge = he.Edge;
JCVSite topsite = edge.Sites[1];
bool rightOfSite = (p.X > topsite.X);
if (rightOfSite ^ he.directionIsRight) //direction and rightOfSite don't match
{
return(rightOfSite);
}
float dxp, dyp, dxs, t1, t2, t3, yl;
bool above;
if (edge.A == 1)
{
dyp = p.Y - topsite.Y;
dxp = p.X - topsite.X;
bool fast = false;
if ((!rightOfSite & (edge.B < 0)) || (rightOfSite & (edge.B >= 0)))
{
above = dyp >= edge.B * dxp;
fast = above;
}
else
{
above = (p.X + p.Y * edge.B) > edge.C;
if (edge.B < 0)
{
above = !above;
}
if (!above)
{
fast = true;
}
}
if (!fast)
{
dxs = topsite.X - edge.Sites[0].X;
above = edge.B * (dxp * dxp - dyp * dyp)
< dxs * dyp * (1 + 2 * dxp / dxs + edge.B * edge.B);
if (edge.B < 0)
{
above = !above;
}
}
}
else // edge.b == 1
{
yl = edge.C - edge.A * p.X;
t1 = p.Y - yl;
t2 = p.X - topsite.X;
t3 = yl - topsite.Y;
above = t1 * t1 > (t2 * t2 + t3 * t3);
}
return(he.directionIsRight ^ above);
}
private void CircleEvent()
{
JCVHalfEdge left = priorityQueue.First();
priorityQueue.Remove(left);
JCVHalfEdge leftleft = left.left;
JCVHalfEdge right = left.right;
JCVHalfEdge rightright = right.right;
JCVSite bottom = left.lSite;
JCVSite top = right.rSite;
PointF vertex = left.vertex;
EndPoints(left.Edge, vertex, left.directionIsRight);
EndPoints(right.Edge, vertex, right.directionIsRight);
lastInserted = rightright;
priorityQueue.Remove(right);
left.Unlink();
right.Unlink();
bool dirIsRight = false;
if (bottom.Y > top.Y)
{
JCVSite temp = bottom;
bottom = top;
top = temp;
dirIsRight = true;
}
JCVEdge edge = new JCVEdge(bottom, top);
edges.Add(edge);
JCVHalfEdge he = new JCVHalfEdge(edge, dirIsRight, leftleft);
EndPoints(edge, vertex, !dirIsRight);
PointF p;
if (CheckCircleEvent(leftleft, he, out p))
{
priorityQueue.Remove(leftleft);
leftleft.vertex = p;
leftleft.Y = p.Y + PointDistance(bottom.center, p);
priorityQueue.Add(leftleft);
}
if (CheckCircleEvent(he, rightright, out p))
{
he.vertex = p;
he.Y = p.Y + PointDistance(bottom.center, p);
priorityQueue.Add(he);
}
}
private float calcAngle(JCVSite site)
{
// We take the average of the two points, since we can better distinguish between very small edges
float x = (Points[0].X + Points[1].X) / 2;
float y = (Points[0].Y + Points[1].Y) / 2;
float diffy = y - site.Y;
float angle = (float)Math.Atan2(diffy, x - site.X);
if (diffy < 0)
{
angle = (float)(angle + 2 * Math.PI);
}
return(angle);
}
public JCVEdge(JCVSite site1, JCVSite site2)
{
Points = new PointF[2];
Sites = new JCVSite[2];
Next = null;
Sites[0] = site1;
Sites[1] = site2;
Points[0].X = JCV_INVALID_VALUE;
Points[0].Y = JCV_INVALID_VALUE;
Points[1].X = JCV_INVALID_VALUE;
Points[1].Y = JCV_INVALID_VALUE;
// Create line equation between S1 and S2:
// float a = -1 * (site2.Y - site1.Y);
// float b = site2.X - site1.X;
// //float c = -1 * (site2.X - site1.X) * site1.Y + (site2.Y - site1.Y) * site1.X;
//
// // create perpendicular line
// float pa = b;
// float pb = -a;
// //float pc = pa * site1.X + pb * site1.Y;
//
// // Move to the mid point
// float mx = site1.X + dx * float(0.5);
// float my = site1.Y + dy * float(0.5);
// float pc = ( pa * mx + pb * my );
float dx = site2.X - site1.X;
float dy = site2.Y - site1.Y;
bool dx_is_larger = (dx * dx) > (dy * dy); // instead of fabs
// Simplify it, using dx and dy
C = dx * (site1.X + dx * 0.5f) + dy * (site1.Y + dy * 0.5f);
if (dx_is_larger)
{
A = (float)1;
B = dy / dx;
C /= dx;
}
else
{
A = dx / dy;
B = (float)1;
C /= dy;
}
}
// They're sorted CCW, so if the current->pos[1] != next->pos[0], then we have a gap
public override bool FillGaps(JCVSite site, JCVDiagram diagram)
{
if (site.edges.Count == 0) //no edges, must be single cell graph
{
if (diagram.sites.Count != 0)
{
throw new Exception("Invalid graph: edgeless site in graph");
}
PointF[] points = new PointF[2];
points[0] = new PointF(boundingBox.Left, boundingBox.Top);
points[1] = new PointF(boundingBox.Right, boundingBox.Top);
JCVEdge edge = new JCVEdge(site, points);
diagram.edges.Add(edge);
JCVGraphEdge gap = new JCVGraphEdge(edge, site, null, points);
site.edges.Add(gap);
}
if (site.edges.Count == 1) // one edge, assume corner gap
{
JCVGraphEdge current = site.edges[0];
PointF[] points = new PointF[2];
points[0] = current.Points[1];
if (current.Points[1].X < boundingBox.Right && current.Points[1].Y == boundingBox.Top)
{
points[1] = new PointF(boundingBox.Right, boundingBox.Top);
}
else if (current.Points[1].X > boundingBox.Left && current.Points[1].Y == boundingBox.Bottom)
{
points[1] = new PointF(boundingBox.Left, boundingBox.Bottom);
}
else if (current.Points[1].Y > boundingBox.Top && current.Points[1].X == boundingBox.Left)
{
points[1] = new PointF(boundingBox.Left, boundingBox.Top);
}
else if (current.Points[1].Y < boundingBox.Bottom && current.Points[1].X == boundingBox.Right)
{
points[1] = new PointF(boundingBox.Right, boundingBox.Bottom);
}
JCVEdge edge = new JCVEdge(site, points);
diagram.edges.Add(edge);
JCVGraphEdge gap = new JCVGraphEdge(edge, site, null, points);
site.edges.Add(gap);
}
int eIndex = 0;
while (eIndex < site.edges.Count)
{
JCVGraphEdge current = site.edges[eIndex];
JCVGraphEdge next = site.edges[(eIndex + 1) % site.edges.Count];
if (PointIsOnEdge(current.Points[1]) && current.Points[1] != next.Points[0])
{
//border gap
if (current.Points[1].X == next.Points[0].X || current.Points[1].Y == next.Points[0].Y)
{
PointF[] points = { current.Points[1], next.Points[0] };
JCVEdge edge = new JCVEdge(site, points);
diagram.edges.Add(edge);
JCVGraphEdge gap = new JCVGraphEdge(edge, site, null, points);
// note: performance of repeated insertions may justify switching to linked list or SortedSet structure
// for processing phase; List currently used due to ease of use, and fact that it will be as fast or
// faster than other structures when the diagram is later used (post generation)
site.edges.Insert(eIndex + 1, gap);
}
else if (PointIsOnEdge(current.Points[1]) && PointIsOnEdge(next.Points[0]))
{
PointF[] points = new PointF[2];
points[0] = current.Points[1];
if (current.Points[1].X < boundingBox.Right && current.Points[1].Y == boundingBox.Top)
{
points[1] = new PointF(boundingBox.Right, boundingBox.Top);
}
else if (current.Points[1].X > boundingBox.Left && current.Points[1].Y == boundingBox.Bottom)
{
points[1] = new PointF(boundingBox.Left, boundingBox.Bottom);
}
else if (current.Points[1].Y > boundingBox.Top && current.Points[1].X == boundingBox.Left)
{
points[1] = new PointF(boundingBox.Left, boundingBox.Top);
}
else if (current.Points[1].Y < boundingBox.Bottom && current.Points[1].X == boundingBox.Right)
{
points[1] = new PointF(boundingBox.Right, boundingBox.Bottom);
}
JCVEdge edge = new JCVEdge(site, points);
diagram.edges.Add(edge);
JCVGraphEdge gap = new JCVGraphEdge(edge, site, null, points);
site.edges.Insert(eIndex + 1, gap);
}
else
{
//something went wrong; abort instead of looping indefinitely
throw new Exception("Invalid Gap state, site location " + site.center.ToString());
}
}
eIndex++;
}
// current = current->next;
// if (current)
// {
// next = current->next;
// if (!next)
// next = site->edges;
// }
//}
////*********** moved down from top ****************
//jcv_graphedge* current = site->edges;
//if (!current)
//{
// // No edges, then it should be a single cell
// assert(allocator->numsites == 1);
// jcv_graphedge* gap = jcv_alloc_graphedge(allocator);
// gap->neighbor = 0;
// gap->pos[0] = clipper->min;
// gap->pos[1].x = clipper->max.x;
// gap->pos[1].y = clipper->min.y;
// gap->angle = jcv_calc_sort_metric(site, gap);
// gap->next = 0;
// gap->edge = jcv_create_gap_edge(allocator, site, gap);
// current = gap;
// site->edges = gap;
//}
//jcv_graphedge* next = current->next;
//if (!next)
//{
// // Only one edge, then we assume it's a corner gap
// jcv_graphedge* gap = jcv_alloc_graphedge(allocator);
// jcv_create_corner_edge(allocator, site, current, gap);
// gap->edge = jcv_create_gap_edge(allocator, site, gap);
// gap->next = current->next;
// current->next = gap;
// current = gap;
// next = site->edges;
//}
return(false);
}
public abstract bool FillGaps(JCVSite site, JCVDiagram diagram);
