void append_segment(ref Segment2d seg)
{
int idx = segments.size;
segments.push_back(seg);
grid.InsertSegment(idx, seg.Center, seg.Extent);
}
private void FilterSelfOverlaps(double overlapRadius, bool bResample = true)
{
// [RMS] this tolerance business is not workign properly right now. The problem is
// that decimator loses corners!
// To simplify the computation we are going to resample the curve so that no adjacent
// are within a given distance. Then we can use distance-to-segments, with the two adjacent
// segments filtered out, to measure self-distance
double dist_thresh = overlapRadius;
double sharp_thresh_deg = 45;
//Profiler.Start("InitialResample");
// resample graph. the degenerate-edge thing is necessary to
// filter out tiny segments that are functionally sharp corners,
// but geometrically are made of multiple angles < threshold
// (maybe there is a better way to do this?)
DGraph2Resampler r = new DGraph2Resampler(Graph);
r.CollapseDegenerateEdges(overlapRadius / 10);
if (bResample)
{
r.SplitToMaxEdgeLength(overlapRadius / 2);
r.CollapseToMinEdgeLength(overlapRadius / 3);
}
r.CollapseDegenerateEdges(overlapRadius / 10);
//Profiler.StopAndAccumulate("InitialResample");
//Profiler.Start("SharpCorners");
// find sharp corners
List <int> sharp_corners = new List <int>();
foreach (int vid in Graph.VertexIndices())
{
if (is_fixed_v(vid))
{
continue;
}
double open_angle = Graph.OpeningAngle(vid);
if (open_angle < sharp_thresh_deg)
{
sharp_corners.Add(vid);
}
}
// disconnect at sharp corners
foreach (int vid in sharp_corners)
{
if (Graph.IsVertex(vid) == false)
{
continue;
}
int e0 = Graph.GetVtxEdges(vid)[0];
Index2i ev = Graph.GetEdgeV(e0);
int otherv = (ev.a == vid) ? ev.b : ev.a;
Vector2d newpos = Graph.GetVertex(vid); //0.5 * (Graph.GetVertex(vid) + Graph.GetVertex(otherv));
Graph.RemoveEdge(e0, false);
int newvid = Graph.AppendVertex(newpos);
Graph.AppendEdge(newvid, otherv);
}
//Profiler.StopAndAccumulate("SharpCorners");
//Profiler.Start("HashTable");
// build edge hash table (cell size is just a ballpark guess here...)
edge_hash = new SegmentHashGrid2d <int>(3 * overlapRadius, -1);
foreach (int eid in Graph.EdgeIndices())
{
Segment2d seg = Graph.GetEdgeSegment(eid);
edge_hash.InsertSegment(eid, seg.Center, seg.Extent);
}
if (CollisionGraph.EdgeCount > 0)
{
collision_edge_hash = new SegmentHashGrid2d <int>(3 * CollisionRadius, -1);
foreach (int eid in CollisionGraph.EdgeIndices())
{
Segment2d seg = CollisionGraph.GetEdgeSegment(eid);
collision_edge_hash.InsertSegment(eid, seg.Center, seg.Extent);
}
}
//Profiler.StopAndAccumulate("HashTable");
//Profiler.Start("Erode1");
// Step 1: erode from boundary vertices
List <int> boundaries = new List <int>();
foreach (int vid in Graph.VertexIndices())
{
if (Graph.GetVtxEdgeCount(vid) == 1)
{
boundaries.Add(vid);
}
}
foreach (int vid in boundaries)
{
if (Graph.IsVertex(vid) == false)
{
continue;
}
double dist = MinSelfSegDistance(vid, 2 * dist_thresh);
double collision_dist = MinCollisionConstraintDistance(vid, CollisionRadius);
if (dist < dist_thresh || collision_dist < CollisionRadius)
{
int eid = Graph.GetVtxEdges(vid)[0];
decimate_forward(vid, eid, dist_thresh);
}
}
//Profiler.StopAndAccumulate("Erode1");
//Profiler.Start("OpenAngleSort");
//
// Step 2: find any other possible self-overlaps and erode them.
//
// sort all vertices by opening angle. For any overlap, we can erode
// on either side. Prefer to erode on side with higher curvature.
List <Vector2d> remaining_v = new List <Vector2d>(Graph.MaxVertexID);
foreach (int vid in Graph.VertexIndices())
{
if (is_fixed_v(vid))
{
continue;
}
double open_angle = Graph.OpeningAngle(vid);
if (open_angle == double.MaxValue)
{
continue;
}
remaining_v.Add(new Vector2d(vid, open_angle));
}
remaining_v.Sort((a, b) => { return((a.y < b.y) ? -1 : (a.y > b.y ? 1 : 0)); });
//Profiler.StopAndAccumulate("OpenAngleSort");
//Profiler.Start("Erode2");
// look for overlap vertices. When we find one, erode on both sides.
foreach (Vector2d vinfo in remaining_v)
{
int vid = (int)vinfo.x;
if (Graph.IsVertex(vid) == false)
{
continue;
}
double dist = MinSelfSegDistance(vid, 2 * dist_thresh);
if (dist < dist_thresh)
{
List <int> nbrs = new List <int>(Graph.GetVtxEdges(vid));
foreach (int eid in nbrs)
{
if (Graph.IsEdge(eid)) // may have been decimated!
{
decimate_forward(vid, eid, dist_thresh);
}
}
}
}
//Profiler.StopAndAccumulate("Erode2");
//Profiler.Start("FlatCollapse");
// get rid of extra vertices
r.CollapseFlatVertices(FinalFlatCollapseAngleThreshDeg);
//Profiler.StopAndAccumulate("FlatCollapse");
}
