/// <summary>
/// Resample curve so that:
/// - if opening angle at vertex is > sharp_thresh, we emit two more vertices at +/- corner_t, where the t is used in prev/next lerps
/// - if opening angle is > flat_thresh, we skip the vertex entirely (simplification)
/// This is mainly useful to get nicer polylines to use as the basis for (eg) creating 3D tubes, rendering, etc
///
/// [TODO] skip tiny segments?
/// </summary>
public DCurve3 ResampleSharpTurns(double sharp_thresh = 90, double flat_thresh = 189, double corner_t = 0.01)
{
int NV = vertices.Count;
DCurve3 resampled = new DCurve3()
{
Closed = this.Closed
};
double prev_t = 1.0 - corner_t;
for (int k = 0; k < NV; ++k)
{
double open_angle = Math.Abs(OpeningAngleDeg(k));
if (open_angle > flat_thresh && k > 0)
{
// ignore skip this vertex
}
else if (open_angle > sharp_thresh)
{
resampled.AppendVertex(vertices[k]);
}
else
{
Vector3d n = vertices[(k + 1) % NV];
Vector3d p = vertices[k == 0 ? NV - 1 : k - 1];
resampled.AppendVertex(Vector3d.Lerp(p, vertices[k], prev_t));
resampled.AppendVertex(vertices[k]);
resampled.AppendVertex(Vector3d.Lerp(vertices[k], n, corner_t));
}
}
return(resampled);
}
/// <summary>
/// Creates g3.DCurve from Vector3[]
/// </summary>
/// <param name="curve">DCurve</param>
/// <param name="verteces">Vextor3[]</param>
/// <param name="bClosed">whether the line is closed</param>
public static void Vector3(this g3.DCurve3 curve, Vector3[] verteces, bool bClosed)
{
curve.ClearVertices();
curve.Closed = bClosed;
foreach (Vector3 vertex in verteces)
{
curve.AppendVertex(vertex);
}
}
public void Make(DCurve3 c)
{
int nV = vertices.Count;
for (int i = 0; i < nV; ++i)
{
c.AppendVertex(vertices[i]);
}
c.Closed = closed;
}
public static DCurve3 ExtractLoopV(IMesh mesh, int[] vertices)
{
DCurve3 curve = new DCurve3();
for (int i = 0; i < vertices.Length; ++i)
{
curve.AppendVertex(mesh.GetVertex(vertices[i]));
}
curve.Closed = true;
return(curve);
}
public static DCurve3 ExtractLoopV(IMesh mesh, IEnumerable <int> vertices)
{
DCurve3 curve = new DCurve3();
foreach (int vid in vertices)
{
curve.AppendVertex(mesh.GetVertex(vid));
}
curve.Closed = true;
return(curve);
}
public static void Restore(DCurve3 curve, BinaryReader reader)
{
curve.Closed = reader.ReadBoolean();
int count = reader.ReadInt32();
for (int i = 0; i < count; ++i)
{
double x = reader.ReadDouble();
double y = reader.ReadDouble();
double z = reader.ReadDouble();
curve.AppendVertex(new Vector3d(x, y, z));
}
}
/// <summary>
/// Decompose graph into simple polylines and polygons.
/// </summary>
public static Curves ExtractCurves(DGraph3 graph)
{
Curves c = new Curves();
c.Loops = new List <DCurve3>();
c.Paths = new List <DCurve3>();
HashSet <int> used = new HashSet <int>();
// find boundary and junction vertices
HashSet <int> boundaries = new HashSet <int>();
HashSet <int> junctions = new HashSet <int>();
foreach (int vid in graph.VertexIndices())
{
if (graph.IsBoundaryVertex(vid))
{
boundaries.Add(vid);
}
if (graph.IsJunctionVertex(vid))
{
junctions.Add(vid);
}
}
// walk paths from boundary vertices
foreach (int start_vid in boundaries)
{
int vid = start_vid;
int eid = graph.GetVtxEdges(vid)[0];
if (used.Contains(eid))
{
continue;
}
DCurve3 path = new DCurve3()
{
Closed = false
};
path.AppendVertex(graph.GetVertex(vid));
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
path.AppendVertex(graph.GetVertex(vid));
if (boundaries.Contains(vid) || junctions.Contains(vid))
{
break; // done!
}
}
c.Paths.Add(path);
}
// ok we should be done w/ boundary verts now...
boundaries.Clear();
foreach (int start_vid in junctions)
{
foreach (int outgoing_eid in graph.VtxEdgesItr(start_vid))
{
if (used.Contains(outgoing_eid))
{
continue;
}
int vid = start_vid;
int eid = outgoing_eid;
DCurve3 path = new DCurve3()
{
Closed = false
};
path.AppendVertex(graph.GetVertex(vid));
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
path.AppendVertex(graph.GetVertex(vid));
if (eid == int.MaxValue || junctions.Contains(vid))
{
break; // done!
}
}
// we could end up back at our start junction vertex!
if (vid == start_vid)
{
path.RemoveVertex(path.VertexCount - 1);
path.Closed = true;
c.Loops.Add(path);
// need to mark incoming edge as used...but is it valid now?
//Util.gDevAssert(eid != int.MaxValue);
if (eid != int.MaxValue)
{
used.Add(eid);
}
}
else
{
c.Paths.Add(path);
}
}
}
// all that should be left are continuous loops...
foreach (int start_eid in graph.EdgeIndices())
{
if (used.Contains(start_eid))
{
continue;
}
int eid = start_eid;
Index2i ev = graph.GetEdgeV(eid);
int vid = ev.a;
DCurve3 poly = new DCurve3()
{
Closed = true
};
poly.AppendVertex(graph.GetVertex(vid));
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
poly.AppendVertex(graph.GetVertex(vid));
if (eid == int.MaxValue || junctions.Contains(vid))
{
throw new Exception("how did this happen??");
}
if (used.Contains(eid))
{
break;
}
}
poly.RemoveVertex(poly.VertexCount - 1);
c.Loops.Add(poly);
}
return(c);
}
/// <summary>
/// Decompose graph into simple polylines and polygons.
/// </summary>
public static Curves ExtractCurves(DGraph3 graph,
bool bWantLoopIndices = false,
Func <int, bool> CurveOrientationF = null)
{
var c = new Curves();
c.Loops = new List <DCurve3>();
c.Paths = new List <DCurve3>();
if (bWantLoopIndices)
{
c.LoopEdges = new List <List <int> >();
c.PathEdges = new List <List <int> >();
}
var used = new HashSet <int>();
// find boundary and junction vertices
var boundaries = new HashSet <int>();
var junctions = new HashSet <int>();
foreach (int vid in graph.VertexIndices())
{
if (graph.IsBoundaryVertex(vid))
{
boundaries.Add(vid);
}
if (graph.IsJunctionVertex(vid))
{
junctions.Add(vid);
}
}
// walk paths from boundary vertices
foreach (int start_vid in boundaries)
{
int vid = start_vid;
int eid = graph.GetVtxEdges(vid)[0];
if (used.Contains(eid))
{
continue;
}
bool reverse = (CurveOrientationF != null) ? CurveOrientationF(eid) : false;
var path = new DCurve3()
{
Closed = false
};
List <int> pathE = (bWantLoopIndices) ? new List <int>() : null;
path.AppendVertex(graph.GetVertex(vid));
if (pathE != null)
{
pathE.Add(eid);
}
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
path.AppendVertex(graph.GetVertex(vid));
if (boundaries.Contains(vid) || junctions.Contains(vid))
{
break; // done!
}
if (pathE != null)
{
pathE.Add(eid);
}
}
if (reverse)
{
path.Reverse();
}
c.Paths.Add(path);
if (pathE != null)
{
Util.gDevAssert(pathE.Count == path.VertexCount - 1);
if (reverse)
{
pathE.Reverse();
}
c.PathEdges.Add(pathE);
}
}
// ok we should be done w/ boundary verts now...
//boundaries.Clear();
c.BoundaryV = boundaries;
foreach (int start_vid in junctions)
{
foreach (int outgoing_eid in graph.VtxEdgesItr(start_vid))
{
if (used.Contains(outgoing_eid))
{
continue;
}
int vid = start_vid;
int eid = outgoing_eid;
bool reverse = (CurveOrientationF != null) ? CurveOrientationF(eid) : false;
var path = new DCurve3()
{
Closed = false
};
List <int> pathE = (bWantLoopIndices) ? new List <int>() : null;
path.AppendVertex(graph.GetVertex(vid));
if (pathE != null)
{
pathE.Add(eid);
}
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
path.AppendVertex(graph.GetVertex(vid));
if (eid == int.MaxValue || junctions.Contains(vid))
{
break; // done!
}
if (pathE != null)
{
pathE.Add(eid);
}
}
// we could end up back at our start junction vertex!
if (vid == start_vid)
{
path.RemoveVertex(path.VertexCount - 1);
path.Closed = true;
if (reverse)
{
path.Reverse();
}
c.Loops.Add(path);
if (pathE != null)
{
Util.gDevAssert(pathE.Count == path.VertexCount);
if (reverse)
{
pathE.Reverse();
}
c.LoopEdges.Add(pathE);
}
// need to mark incoming edge as used...but is it valid now?
//Util.gDevAssert(eid != int.MaxValue);
if (eid != int.MaxValue)
{
used.Add(eid);
}
}
else
{
if (reverse)
{
path.Reverse();
}
c.Paths.Add(path);
if (pathE != null)
{
Util.gDevAssert(pathE.Count == path.VertexCount - 1);
if (reverse)
{
pathE.Reverse();
}
c.PathEdges.Add(pathE);
}
}
}
}
c.JunctionV = junctions;
// all that should be left are continuous loops...
foreach (int start_eid in graph.EdgeIndices())
{
if (used.Contains(start_eid))
{
continue;
}
int eid = start_eid;
Index2i ev = graph.GetEdgeV(eid);
int vid = ev.a;
bool reverse = (CurveOrientationF != null) ? CurveOrientationF(eid) : false;
var poly = new DCurve3()
{
Closed = true
};
List <int> polyE = (bWantLoopIndices) ? new List <int>() : null;
poly.AppendVertex(graph.GetVertex(vid));
if (polyE != null)
{
polyE.Add(eid);
}
while (true)
{
used.Add(eid);
Index2i next = NextEdgeAndVtx(eid, vid, graph);
eid = next.a;
vid = next.b;
poly.AppendVertex(graph.GetVertex(vid));
if (polyE != null)
{
polyE.Add(eid);
}
if (eid == int.MaxValue || junctions.Contains(vid))
{
throw new Exception("how did this happen??");
}
if (used.Contains(eid))
{
break;
}
}
poly.RemoveVertex(poly.VertexCount - 1);
if (reverse)
{
poly.Reverse();
}
c.Loops.Add(poly);
if (polyE != null)
{
polyE.RemoveAt(polyE.Count - 1);
Util.gDevAssert(polyE.Count == poly.VertexCount);
if (reverse)
{
polyE.Reverse();
}
c.LoopEdges.Add(polyE);
}
}
return(c);
}
