static bool LocalConstraints(Segment segment, List <Segment> segments, Quadtree quadtree, DebugData debugData)
{
int priority = 0;
Func <bool> action = null;
float t0 = -1;
var matches = quadtree.Retrieve(segment);
for (int i = 0, j = 0, k = matches.Count - 1; j <= k; i = j += 1)
{
Segment other = (Segment)matches[i].reference;
if (segment == other)
{
continue;
}
// intersection check
if (priority <= 4)
{
Vector2 intersection;
float t1;
if (segment.Intersect(other, out intersection, out t1))
{
if (t0 == -1 || t1 < t0)
{
t0 = t1;
priority = 4;
action = () =>
{
float dirDiff = Mathf.Abs(other.Direction - segment.Direction) % 180.0f;
float minDirectionDiff = Mathf.Min(dirDiff, Mathf.Abs(dirDiff - 180.0f));
if (minDirectionDiff < Config.minIntersectionDeviation)
{
return(false);
}
IntersectSegments(intersection, other, segment, segments, quadtree);
if (debugData != null)
{
debugData.intersections.Add(intersection);
}
return(true);
};
}
}
}
// snap to crossing within radius check
if (priority <= 3)
{
if ((segment.End - other.End).magnitude <= Config.snapDistance)
{
priority = 3;
action = () =>
{
List <Segment> links;
segment.End = other.End;
segment.Severed = true;
foreach (var destination in segment.Destinations)
{
int index = destination.Sources.IndexOf(other);
if (index != -1)
{
continue;
}
destination.Sources.Add(other);
}
links = other.StartIsBackwards() ? other.Forwards : other.Branches;
if (links.Any((Segment link) =>
{
return(((link.Start == segment.End) &&
(link.End == segment.Start)) ||
((link.Start == segment.Start) && (link.End == segment.End)));
}))
{
return(false);
}
links.ForEach((Segment link) =>
{
link.LinksForEndContaining(other).Add(segment);
segment.Forwards.Add(link);
});
links.Add(segment);
segment.Forwards.Add(other);
if (debugData != null)
{
debugData.snaps.Add(other.End);
}
return(true);
};
}
}
// intersection within radius check
if (priority <= 2)
{
var e0 = (segment.End - other.Start);
var e1 = (other.End - other.Start);
Vector2 proj = Vector3.Project(e0, e1);
Vector2 pointOnLine = (other.Start + proj);
float distance2 = Vector2.SqrMagnitude(segment.End - pointOnLine);
float lineProj2 = Mathf.Sign(Vector3.Dot(e0, e1)) * Vector2.SqrMagnitude(proj);
float length2 = Vector2.SqrMagnitude(e1);
if (distance2 < Config.snapDistance * Config.snapDistance && lineProj2 >= 0 && lineProj2 <= length2)
{
Vector2 point;
point = pointOnLine;
priority = 2;
action = () =>
{
float dirDiff = Math.Abs(other.Direction - segment.Direction) % 180.0f;
float minDirDiff = Math.Min(dirDiff, Math.Abs(dirDiff - 180.0f));
if (minDirDiff < Config.minIntersectionDeviation)
{
return(false);
}
IntersectSegments(point, other, segment, segments, quadtree);
if (debugData != null)
{
debugData.intersectionsRadius.Add(point);
}
return(true);
};
}
}
}
if (action != null)
{
return(action());
}
return(true);
}
static void IntersectSegments(Vector2 intersection, Segment segment0, Segment segment1, List <Segment> segments, Quadtree quadtree)
{
bool startIsBackwards = segment0.StartIsBackwards();
Segment splitPart = new Segment(segment0);
splitPart.Destinations.Add(segment0);
AddSegment(splitPart, segments, quadtree);
splitPart.End = intersection;
segment0.Start = intersection;
foreach (var source0 in segment0.Sources)
{
int index = source0.Destinations.IndexOf(segment0);
if (index == -1)
{
continue;
}
source0.Destinations[index] = splitPart;
}
splitPart.Sources = new List <Segment>(segment0.Sources);
segment0.Sources.Clear();
segment0.Sources.Add(splitPart);
segment0.Sources.Add(segment1);
splitPart.Branches = new List <Segment>(segment0.Branches);
splitPart.Forwards = new List <Segment>(segment0.Forwards);
Segment firstSplit, secondSplit;
List <Segment> linksToFix;
if (startIsBackwards)
{
firstSplit = splitPart;
secondSplit = segment0;
linksToFix = splitPart.Branches;
}
else
{
firstSplit = segment0;
secondSplit = splitPart;
linksToFix = splitPart.Forwards;
}
foreach (var link in linksToFix)
{
int index = link.Branches.IndexOf(segment0);
if (index != -1)
{
link.Branches[index] = splitPart;
}
else
{
index = link.Forwards.IndexOf(segment0);
link.Forwards[index] = splitPart;
}
}
firstSplit.Forwards = new List <Segment>();
firstSplit.Forwards.Add(segment1);
firstSplit.Forwards.Add(secondSplit);
secondSplit.Branches = new List <Segment>();
secondSplit.Branches.Add(segment1);
secondSplit.Branches.Add(firstSplit);
segment1.Forwards.Add(firstSplit);
segment1.Forwards.Add(secondSplit);
segment1.End = intersection;
segment1.Destinations.Clear();
segment1.Severed = true;
}
