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");
}
/// <summary>
/// fill poly w/ adjacent straight line segments, connected by connectors
/// </summary>
protected FillCurveSet2d ComputeFillPaths(GeneralPolygon2d poly)
{
FillCurveSet2d paths = new FillCurveSet2d();
// smooth the input poly a little bit, this simplifies the filling
// (simplify after?)
//GeneralPolygon2d smoothed = poly.Duplicate();
//CurveUtils2.LaplacianSmoothConstrained(smoothed, 0.5, 5, ToolWidth / 2, true, false);
//poly = smoothed;
// compute 2D non-manifold graph consisting of original polygon and
// inserted line segments
DGraph2 spanGraph = ComputeSpanGraph(poly);
if (spanGraph == null || spanGraph.VertexCount == poly.VertexCount)
{
return(paths);
}
DGraph2 pathGraph = BuildPathGraph(spanGraph);
// filter out self-overlaps from graph
if (FilterSelfOverlaps)
{
PathOverlapRepair repair = new PathOverlapRepair(pathGraph);
repair.OverlapRadius = ToolWidth * SelfOverlapToolWidthX;
repair.PreserveEdgeFilterF = (eid) => {
return(repair.Graph.GetEdgeGroup(eid) > 0);
};
repair.Compute();
pathGraph = repair.GetResultGraph();
}
HashSet <int> boundaries = new HashSet <int>();
foreach (int vid in pathGraph.VertexIndices())
{
if (pathGraph.IsBoundaryVertex(vid))
{
boundaries.Add(vid);
}
if (pathGraph.IsJunctionVertex(vid))
{
throw new Exception("DenseLinesFillPolygon: PathGraph has a junction???");
}
}
// walk paths from boundary vertices
while (boundaries.Count > 0)
{
int start_vid = boundaries.First();
boundaries.Remove(start_vid);
int vid = start_vid;
int eid = pathGraph.GetVtxEdges(vid)[0];
FillPolyline2d path = new FillPolyline2d()
{
TypeFlags = this.TypeFlags
};
path.AppendVertex(pathGraph.GetVertex(vid));
while (true)
{
Index2i next = DGraph2Util.NextEdgeAndVtx(eid, vid, pathGraph);
eid = next.a;
vid = next.b;
int gid = pathGraph.GetEdgeGroup(eid);
if (gid < 0)
{
path.AppendVertex(pathGraph.GetVertex(vid), TPVertexFlags.IsConnector);
}
else
{
path.AppendVertex(pathGraph.GetVertex(vid));
}
if (boundaries.Contains(vid))
{
boundaries.Remove(vid);
break;
}
}
// discard paths that are too short
if (path.ArcLength < MinPathLengthMM)
{
continue;
}
// run polyline simplification to get rid of unneccesary detail in connectors
// [TODO] we could do this at graph level...)
// [TODO] maybe should be checkign for collisions? we could end up creating
// non-trivial overlaps here...
if (SimplifyAmount != SimplificationLevel.None && path.VertexCount > 2)
{
PolySimplification2 simp = new PolySimplification2(path);
switch (SimplifyAmount)
{
default:
case SimplificationLevel.Minor:
simp.SimplifyDeviationThreshold = ToolWidth / 4; break;
case SimplificationLevel.Aggressive:
simp.SimplifyDeviationThreshold = ToolWidth; break;
case SimplificationLevel.Moderate:
simp.SimplifyDeviationThreshold = ToolWidth / 2; break;
}
simp.Simplify();
path = new FillPolyline2d(simp.Result.ToArray())
{
TypeFlags = this.TypeFlags
};
}
paths.Append(path);
}
// Check to make sure that we are not putting way too much material in the
// available volume. Computes extrusion volume from path length and if the
// ratio is too high, scales down the path thickness
// TODO: do we need to compute volume? If we just divide everything by
// height we get the same scaling, no? Then we don't need layer height.
if (MaxOverfillRatio > 0)
{
throw new NotImplementedException("this is not finished yet");
#if false
double LayerHeight = 0.2; // AAAHHH hardcoded nonono
double len = paths.TotalLength();
double extrude_vol = ExtrusionMath.PathLengthToVolume(LayerHeight, ToolWidth, len);
double polygon_vol = LayerHeight * Math.Abs(poly.Area);
double ratio = extrude_vol / polygon_vol;
if (ratio > MaxOverfillRatio && PathSpacing == ToolWidth)
{
double use_width = ExtrusionMath.WidthFromTargetVolume(LayerHeight, len, polygon_vol);
//System.Console.WriteLine("Extrusion volume: {0} PolyVolume: {1} % {2} ScaledWidth: {3}",
//extrude_vol, polygon_vol, extrude_vol / polygon_vol, use_width);
foreach (var path in paths.Curves)
{
path.CustomThickness = use_width;
}
}
#endif
}
return(paths);
}
protected DGraph2 compute_result(GeneralPolygon2d poly, double fOffset, double fTargetSpacing)
{
double dt = fTargetSpacing / 2;
int nSteps = (int)(Math.Abs(fOffset) / dt);
if (nSteps < 10)
{
nSteps = 10;
}
// [TODO] we could cache this over multiple runs...
DGraph2 graph = new DGraph2();
graph.AppendPolygon(poly.Outer);
foreach (var h in poly.Holes)
{
graph.AppendPolygon(h);
}
// resample to nbrhood of target spacing
SplitToMaxEdgeLength(graph, fTargetSpacing * 1.33);
// build bvtree for polygon
if (poly_tree == null || poly_tree.Polygon != poly)
{
poly_tree = new GeneralPolygon2dBoxTree(poly);
}
// allocate and resize caches as necessary
if (offset_cache == null)
{
offset_cache = new DVector <Vector2d>();
}
if (offset_cache.size < graph.VertexCount)
{
offset_cache.resize(graph.VertexCount * 2);
}
if (position_cache == null)
{
position_cache = new DVector <Vector2d>();
}
if (position_cache.size < graph.VertexCount)
{
position_cache.resize(graph.VertexCount * 2);
}
if (collapse_cache == null)
{
collapse_cache = new DVector <Vector2d>();
}
if (collapse_cache.size < graph.VertexCount)
{
collapse_cache.resize(graph.VertexCount * 2);
}
if (last_step_size == null)
{
last_step_size = new DVector <double>();
}
if (last_step_size.size < graph.VertexCount)
{
last_step_size.resize(graph.VertexCount * 2);
}
// insert all points into a hashgrid. We will dynamically update this grid as we proceed
// [TODO] is this a good bounds-size?
graph_cache = new PointHashGrid2d <int>(poly.Bounds.MaxDim / 64, -1);
foreach (int vid in graph.VertexIndices())
{
graph_cache.InsertPoint(vid, graph.GetVertex(vid));
}
LocalProfiler p = (_enable_profiling) ? new LocalProfiler() : null;
if (_enable_profiling)
{
p.Start("All");
}
// run a bunch of steps. The last few are tuning steps where we use half-steps,
// which seems to help?
int TUNE_STEPS = nSteps / 2;
nSteps *= 2;
for (int i = 0; i < nSteps; ++i)
{
if (_enable_profiling)
{
p.Start("offset");
}
double step_dt = dt;
if (i > nSteps - TUNE_STEPS)
{
step_dt = dt / 2;
}
if (last_step_size.size < graph.VertexCount)
{
last_step_size.resize(graph.VertexCount + 256);
}
// Each vertex steps forward. In fact we compute two steps and average them,
// this helps w/ convergence. To produce more accurate convergence, we track
// the size of the actual step we took at the last round, and use that the next
// time. (The assumption is that the steps will get smaller at the target distance).
gParallel.ForEach(graph.VertexIndices(), (vid) =>
{
// use tracked step size if we have it
double use_dt = step_dt;
if (last_step_size[vid] > 0)
{
use_dt = Math.Min(last_step_size[vid], dt);
}
Vector2d cur_pos = graph.GetVertex(vid);
double err, err_2;
// take two sequential steps and average them. this vastly improves convergence.
Vector2d new_pos = compute_offset_step(cur_pos, poly, fOffset, use_dt, out err);
Vector2d new_pos_2 = compute_offset_step(new_pos, poly, fOffset, use_dt, out err_2);
// weighted blend of points - prefer one w/ smaller error
//double w = 1.0 / Math.Max(err, MathUtil.ZeroTolerancef);
//double w_2 = 1.0 / Math.Max(err_2, MathUtil.ZeroTolerancef);
//new_pos = w * new_pos + w_2 * new_pos_2;
//new_pos /= (w + w_2);
// [RMS] weighted blend doesn't seem to matter if we are tracking per-vertex step size.
new_pos = Vector2d.Lerp(new_pos, new_pos_2, 0.5);
// keep track of actual step we are taking and use that next iteration
double actual_step_dist = cur_pos.Distance(new_pos);
if (last_step_size[vid] == 0)
{
last_step_size[vid] = actual_step_dist;
}
else
{
last_step_size[vid] = (0.75) * last_step_size[vid] + (0.25) * actual_step_dist;
}
// update point in hashtable and graph
graph_cache.UpdatePoint(vid, cur_pos, new_pos);
graph.SetVertex(vid, new_pos);
});
if (_enable_profiling)
{
p.StopAndAccumulate("offset"); p.Start("smooth");
}
// Do a smoothing pass, but for the last few steps, reduce smoothing
// (otherwise it pulls away from target solution)
int smooth_steps = 5; double smooth_alpha = 0.75;
if (i > nSteps - TUNE_STEPS)
{
smooth_steps = 2; smooth_alpha = 0.25;
}
smooth_pass(graph, smooth_steps, smooth_alpha, fTargetSpacing / 2);
if (_enable_profiling)
{
p.StopAndAccumulate("smooth"); p.Start("join");
}
// if a vertex is within targetSpacing from another vertex, and they are
// not geodesically connected in the graph, them we merge/weld them together.
int joined = 0;
do
{
//joined = JoinInTolerance(graph, fMergeThresh);
//joined = JoinInTolerance_Parallel(graph, fMergeThresh);
joined = JoinInTolerance_Parallel_Cache(graph, fTargetSpacing);
} while (joined > 0);
if (_enable_profiling)
{
p.StopAndAccumulate("join"); p.Start("refine");
}
// now do a pass of graph refinement, to collapse short edges and split long ones
CollapseToMinEdgeLength(graph, fTargetSpacing * 0.66f);
SplitToMaxEdgeLength(graph, fTargetSpacing * 1.33);
if (_enable_profiling)
{
p.StopAndAccumulate("refine");
}
}
if (_enable_profiling)
{
p.Stop("All");
System.Console.WriteLine("All: " + p.Elapsed("All"));
System.Console.WriteLine(p.AllAccumulatedTimes());
}
// get rid of junction vertices, if requested
if (DisconnectGraphJunctions)
{
DGraph2Util.DisconnectJunctions(graph);
}
return(graph);
}
public static DGraph2 perturb_fill(DGraph2 graphIn, GeneralPolygon2d bounds, double waveWidth, double stepSize)
{
DGraph2Util.Curves curves = DGraph2Util.ExtractCurves(graphIn);
Polygon2d poly = curves.Loops[0];
GeneralPolygon2dBoxTree gpTree = new GeneralPolygon2dBoxTree(bounds);
Polygon2dBoxTree outerTree = new Polygon2dBoxTree(bounds.Outer);
Polygon2dBoxTree innerTree = new Polygon2dBoxTree(bounds.Holes[0]);
DGraph2 graph = new DGraph2();
graph.EnableVertexColors(Vector3f.Zero);
double len = poly.Perimeter;
int waves = (int)(len / waveWidth);
double lenScale = len / (MathUtil.TwoPI * waves);
double accum_len = 0;
int prev_vid = -1, start_vid = -1;
int N = poly.VertexCount;
for (int k = 0; k < N; ++k)
{
double t = accum_len / lenScale;
t = Math.Cos(t);
//Vector2d normal = poly.GetNormal(k);
Vector2d normal = poly[k].Normalized;
int vid = graph.AppendVertex(poly[k], new Vector3f(t, normal.x, normal.y));
if (prev_vid != -1)
{
graph.AppendEdge(prev_vid, vid);
accum_len += graph.GetVertex(prev_vid).Distance(graph.GetVertex(vid));
}
else
{
start_vid = vid;
}
prev_vid = vid;
}
graph.AppendEdge(prev_vid, start_vid);
Vector2d[] newPos = new Vector2d[graph.MaxVertexID];
for (int k = 0; k < 10; ++k)
{
smooth_pass(graph, 0.5f, newPos);
}
for (int k = 0; k < 20; ++k)
{
foreach (int vid in graph.VertexIndices())
{
Vector2d v = graph.GetVertex(vid);
Vector3f c = graph.GetVertexColor(vid);
float t = c.x;
Vector2d n = new Vector2d(c.y, c.z);
if (k == 0 || Math.Abs(t) > 0.9)
{
v += t * stepSize * n;
if (!bounds.Contains(v))
{
v = gpTree.NearestPoint(v);
}
}
newPos[vid] = v;
}
foreach (int vid in graph.VertexIndices())
{
graph.SetVertex(vid, newPos[vid]);
}
for (int j = 0; j < 5; ++j)
{
smooth_pass(graph, 0.1f, newPos);
}
}
return(graph);
}
public static void test_splitter()
{
Polygon2d poly = Polygon2d.MakeCircle(1000, 16);
Polygon2d hole = Polygon2d.MakeCircle(500, 32); hole.Reverse();
GeneralPolygon2d gpoly = new GeneralPolygon2d(poly);
gpoly.AddHole(hole);
//Polygon2d poly = Polygon2d.MakeRectangle(Vector2d.Zero, 1000, 1000);
DGraph2 graph = new DGraph2();
graph.AppendPolygon(gpoly);
System.Console.WriteLine("Stats before: verts {0} edges {1} ", graph.VertexCount, graph.EdgeCount);
GraphSplitter2d splitter = new GraphSplitter2d(graph);
splitter.InsideTestF = gpoly.Contains;
for (int k = 0; k < poly.VertexCount; ++k)
{
Line2d line = new Line2d(poly[k], Vector2d.AxisY);
splitter.InsertLine(line);
}
System.Console.WriteLine("Stats after 1: verts {0} edges {1} ", graph.VertexCount, graph.EdgeCount);
for (int k = 0; k < poly.VertexCount; ++k)
{
Line2d line = new Line2d(poly[k], Vector2d.AxisX);
splitter.InsertLine(line);
}
for (int k = 0; k < poly.VertexCount; ++k)
{
Line2d line = new Line2d(poly[k], Vector2d.One.Normalized);
splitter.InsertLine(line);
}
for (int k = 0; k < poly.VertexCount; ++k)
{
Line2d line = new Line2d(poly[k], new Vector2d(1, -1).Normalized);
splitter.InsertLine(line);
}
System.Console.WriteLine("Stats after: verts {0} edges {1} ", graph.VertexCount, graph.EdgeCount);
Random r = new Random(31337);
foreach (int vid in graph.VertexIndices())
{
Vector2d v = graph.GetVertex(vid);
v += TestUtil.RandomPoints2(1, r, v, 25)[0];
graph.SetVertex(vid, v);
}
SVGWriter svg = new SVGWriter();
svg.AddGraph(graph);
var vtx_style = SVGWriter.Style.Outline("red", 1.0f);
foreach (int vid in graph.VertexIndices())
{
Vector2d v = graph.GetVertex(vid);
svg.AddCircle(new Circle2d(v, 10), vtx_style);
}
svg.Write(TestUtil.GetTestOutputPath("split_graph.svg"));
}
