/// <summary>
/// if before a flip we have normals (n1,n2) and after we have (m1,m2), check if
/// the dot between any of the 4 pairs changes sign after the flip, or is
/// less than the dot-product tolerance (ie angle tolerance)
/// </summary>
public static bool CheckIfEdgeFlipCreatesFlip(DMesh3 mesh, int eID, double flip_dot_tol = 0.0)
{
Util.gDevAssert(mesh.IsBoundaryEdge(eID) == false);
Index4i einfo = mesh.GetEdge(eID);
Index2i ov = mesh.GetEdgeOpposingV(eID);
int a = einfo.a, b = einfo.b, c = ov.a, d = ov.b;
int t0 = einfo.c;
Vector3d vC = mesh.GetVertex(c), vD = mesh.GetVertex(d);
Index3i tri_v = mesh.GetTriangle(t0);
int oa = a, ob = b;
IndexUtil.orient_tri_edge(ref oa, ref ob, ref tri_v);
Vector3d vOA = mesh.GetVertex(oa), vOB = mesh.GetVertex(ob);
Vector3d n0 = MathUtil.FastNormalDirection(ref vOA, ref vOB, ref vC);
Vector3d n1 = MathUtil.FastNormalDirection(ref vOB, ref vOA, ref vD);
Vector3d f0 = MathUtil.FastNormalDirection(ref vC, ref vD, ref vOB);
if (edge_flip_metric(ref n0, ref f0, flip_dot_tol) <= flip_dot_tol ||
edge_flip_metric(ref n1, ref f0, flip_dot_tol) <= flip_dot_tol)
{
return(true);
}
Vector3d f1 = MathUtil.FastNormalDirection(ref vD, ref vC, ref vOA);
if (edge_flip_metric(ref n0, ref f1, flip_dot_tol) <= flip_dot_tol ||
edge_flip_metric(ref n1, ref f1, flip_dot_tol) <= flip_dot_tol)
{
return(true);
}
return(false);
}
/// <summary>
/// Check if collapsing edge edgeID to point newv will flip normal of any attached face
/// </summary>
public static bool CheckIfCollapseCreatesFlip(DMesh3 mesh, int edgeID, Vector3d newv)
{
Index4i edge_info = mesh.GetEdge(edgeID);
int tc = edge_info.c, td = edge_info.d;
for (int j = 0; j < 2; ++j)
{
int vid = edge_info[j];
int vother = edge_info[(j + 1) % 2];
foreach (int tid in mesh.VtxTrianglesItr(vid))
{
if (tid == tc || tid == td)
{
continue;
}
Index3i curt = mesh.GetTriangle(tid);
if (curt.a == vother || curt.b == vother || curt.c == vother)
{
return(true); // invalid nbrhood for collapse
}
Vector3d va = mesh.GetVertex(curt.a);
Vector3d vb = mesh.GetVertex(curt.b);
Vector3d vc = mesh.GetVertex(curt.c);
Vector3d ncur = (vb - va).Cross(vc - va);
double sign = 0;
if (curt.a == vid)
{
Vector3d nnew = (vb - newv).Cross(vc - newv);
sign = ncur.Dot(nnew);
}
else if (curt.b == vid)
{
Vector3d nnew = (newv - va).Cross(vc - va);
sign = ncur.Dot(nnew);
}
else if (curt.c == vid)
{
Vector3d nnew = (vb - va).Cross(newv - va);
sign = ncur.Dot(nnew);
}
else
{
throw new Exception("should never be here!");
}
if (sign <= 0.0)
{
return(true);
}
}
}
return(false);
}
public static void DebugEdgeInfo(DMesh3 mesh, params int[] edgeIds)
{
foreach (var edgeId in edgeIds)
{
Debug.Write($"Info on edge {edgeId}... ");
if (!mesh.IsEdge(edgeId))
{
Debug.WriteLine("Not an edge.");
continue;
}
var e = mesh.GetEdge(edgeId);
Debug.WriteLine($"IsBorder: {mesh.IsBoundaryEdge(edgeId)}");
var from = mesh.GetVertex(e.a);
var to = mesh.GetVertex(e.b);
Debug.WriteLine($" from: {from.x},{from.y},{from.z} to {to.x},{to.y},{to.z}");
}
}
/// <summary>
/// For given edge, return it's triangles and the triangles that would
/// be created if it was flipped (used in edge-flip optimizers)
/// </summary>
public static void GetEdgeFlipTris(DMesh3 mesh, int eID,
out Index3i orig_t0, out Index3i orig_t1,
out Index3i flip_t0, out Index3i flip_t1)
{
Index4i einfo = mesh.GetEdge(eID);
Index2i ov = mesh.GetEdgeOpposingV(eID);
int a = einfo.a, b = einfo.b, c = ov.a, d = ov.b;
int t0 = einfo.c;
Index3i tri_v = mesh.GetTriangle(t0);
int oa = a, ob = b;
IndexUtil.orient_tri_edge(ref oa, ref ob, ref tri_v);
orig_t0 = new Index3i(oa, ob, c);
orig_t1 = new Index3i(ob, oa, d);
flip_t0 = new Index3i(c, d, ob);
flip_t1 = new Index3i(d, c, oa);
}
/// <summary>
/// For given edge, return normals of it's two triangles, and normals
/// of the triangles created if edge is flipped (used in edge-flip optimizers)
/// </summary>
public static void GetEdgeFlipNormals(DMesh3 mesh, int eID,
out Vector3d n1, out Vector3d n2,
out Vector3d on1, out Vector3d on2)
{
Index4i einfo = mesh.GetEdge(eID);
Index2i ov = mesh.GetEdgeOpposingV(eID);
int a = einfo.a, b = einfo.b, c = ov.a, d = ov.b;
int t0 = einfo.c;
Vector3d vC = mesh.GetVertex(c), vD = mesh.GetVertex(d);
Index3i tri_v = mesh.GetTriangle(t0);
int oa = a, ob = b;
IndexUtil.orient_tri_edge(ref oa, ref ob, ref tri_v);
Vector3d vOA = mesh.GetVertex(oa), vOB = mesh.GetVertex(ob);
n1 = MathUtil.Normal(ref vOA, ref vOB, ref vC);
n2 = MathUtil.Normal(ref vOB, ref vOA, ref vD);
on1 = MathUtil.Normal(ref vC, ref vD, ref vOB);
on2 = MathUtil.Normal(ref vD, ref vC, ref vOA);
}
// Walk along edge loop and collapse to inserted curve vertices.
EdgeLoop simplify(EdgeLoop loop)
{
HashSet <int> curve_verts = new HashSet <int>(CurveVertices);
List <int> remaining_edges = new List <int>();
for (int li = 0; li < loop.EdgeCount; ++li)
{
int eid = loop.Edges[li];
Index2i ev = Mesh.GetEdgeV(eid);
// cannot collapse edge between two "original" polygon verts (ie created by face pokes)
if (curve_verts.Contains(ev.a) && curve_verts.Contains(ev.b))
{
remaining_edges.Add(eid);
continue;
}
// if we have an original vert, we need to keep it (and its position!)
int keep = ev.a, discard = ev.b;
Vector3d set_to = Vector3d.Zero;
if (curve_verts.Contains(ev.b))
{
keep = ev.b;
discard = ev.a;
set_to = Mesh.GetVertex(ev.b);
}
else if (curve_verts.Contains(ev.a))
{
set_to = Mesh.GetVertex(ev.a);
}
else
{
set_to = 0.5 * (Mesh.GetVertex(ev.a) + Mesh.GetVertex(ev.b));
}
// make sure we are not going to flip any normals
// [OPTIMIZATION] May be possible to do this more efficiently because we know we are in
// 2D and each tri should have same cw/ccw orientation. But we don't quite "know" we
// are in 2D here, as CollapseEdge function is operating on the mesh coordinates...
if (MeshUtil.CheckIfCollapseCreatesFlip(Mesh, eid, set_to))
{
remaining_edges.Add(eid);
continue;
}
// cannot collapse if the 'other' edges we would discard are OnCutEdges. This would
// result in loop potentially being broken. bad!
Index4i einfo = Mesh.GetEdge(eid);
int c = IndexUtil.find_tri_other_vtx(keep, discard, Mesh.GetTriangle(einfo.c));
int d = IndexUtil.find_tri_other_vtx(keep, discard, Mesh.GetTriangle(einfo.d));
int ec = Mesh.FindEdge(discard, c);
int ed = Mesh.FindEdge(discard, d);
if (OnCutEdges.Contains(ec) || OnCutEdges.Contains(ed))
{
remaining_edges.Add(eid);
continue;
}
// do collapse and update internal data structures
DMesh3.EdgeCollapseInfo collapse;
MeshResult result = Mesh.CollapseEdge(keep, discard, out collapse);
if (result == MeshResult.Ok)
{
Mesh.SetVertex(collapse.vKept, set_to);
OnCutEdges.Remove(collapse.eCollapsed);
}
else
{
remaining_edges.Add(eid);
}
}
return(EdgeLoop.FromEdges(Mesh, remaining_edges));
}
protected virtual ProcessResult CollapseEdge(int edgeID, Vector3d vNewPos, out int collapseToV)
{
collapseToV = DMesh3.InvalidID;
RuntimeDebugCheck(edgeID);
EdgeConstraint constraint =
(constraints == null) ? EdgeConstraint.Unconstrained : constraints.GetEdgeConstraint(edgeID);
if (constraint.NoModifications)
{
return(ProcessResult.Ignored_EdgeIsFullyConstrained);
}
if (constraint.CanCollapse == false)
{
return(ProcessResult.Ignored_EdgeIsFullyConstrained);
}
// look up verts and tris for this edge
int a = 0, b = 0, t0 = 0, t1 = 0;
if (mesh.GetEdge(edgeID, ref a, ref b, ref t0, ref t1) == false)
{
return(ProcessResult.Failed_NotAnEdge);
}
bool bIsBoundaryEdge = (t1 == DMesh3.InvalidID);
// look up 'other' verts c (from t0) and d (from t1, if it exists)
Index3i T0tv = mesh.GetTriangle(t0);
int c = IndexUtil.find_tri_other_vtx(a, b, T0tv);
Index3i T1tv = (bIsBoundaryEdge) ? DMesh3.InvalidTriangle : mesh.GetTriangle(t1);
int d = (bIsBoundaryEdge) ? DMesh3.InvalidID : IndexUtil.find_tri_other_vtx(a, b, T1tv);
Vector3d vA = mesh.GetVertex(a);
Vector3d vB = mesh.GetVertex(b);
double edge_len_sqr = (vA - vB).LengthSquared;
if (edge_len_sqr > MinEdgeLength * MinEdgeLength)
{
return(ProcessResult.Ignored_EdgeTooLong);
}
begin_collapse();
// check if we should collapse, and also find which vertex we should collapse to,
// in cases where we have constraints/etc
int collapse_to = -1;
bool bCanCollapse = can_collapse_constraints(edgeID, a, b, c, d, t0, t1, out collapse_to);
if (bCanCollapse == false)
{
return(ProcessResult.Ignored_Constrained);
}
// if we have a boundary, we want to collapse to boundary
if (PreserveBoundary && HaveBoundary)
{
if (collapse_to != -1)
{
if ((IsBoundaryV(b) && collapse_to != b) ||
(IsBoundaryV(a) && collapse_to != a))
{
return(ProcessResult.Ignored_Constrained);
}
}
if (IsBoundaryV(b))
{
collapse_to = b;
}
else if (IsBoundaryV(a))
{
collapse_to = a;
}
}
// optimization: if edge cd exists, we cannot collapse or flip. look that up here?
// funcs will do it internally...
// (or maybe we can collapse if cd exists? edge-collapse doesn't check for it explicitly...)
ProcessResult retVal = ProcessResult.Failed_OpNotSuccessful;
int iKeep = b, iCollapse = a;
// if either vtx is fixed, collapse to that position
if (collapse_to == b)
{
vNewPos = vB;
}
else if (collapse_to == a)
{
iKeep = a; iCollapse = b;
vNewPos = vA;
}
else
{
vNewPos = get_projected_collapse_position(iKeep, vNewPos);
}
// check if this collapse will create a normal flip. Also checks
// for invalid collapse nbrhood, since we are doing one-ring iter anyway.
// [TODO] could we skip this one-ring check in CollapseEdge? pass in hints?
if (creates_flip_or_invalid(a, b, ref vNewPos, t0, t1) || creates_flip_or_invalid(b, a, ref vNewPos, t0, t1))
{
retVal = ProcessResult.Ignored_CreatesFlip;
goto skip_to_end;
}
// lots of cases where we cannot collapse, but we should just let
// mesh sort that out, right?
COUNT_COLLAPSES++;
DMesh3.EdgeCollapseInfo collapseInfo;
MeshResult result = mesh.CollapseEdge(iKeep, iCollapse, out collapseInfo);
if (result == MeshResult.Ok)
{
collapseToV = iKeep;
mesh.SetVertex(iKeep, vNewPos);
if (constraints != null)
{
constraints.ClearEdgeConstraint(edgeID);
constraints.ClearEdgeConstraint(collapseInfo.eRemoved0);
if (collapseInfo.eRemoved1 != DMesh3.InvalidID)
{
constraints.ClearEdgeConstraint(collapseInfo.eRemoved1);
}
constraints.ClearVertexConstraint(iCollapse);
}
OnEdgeCollapse(edgeID, iKeep, iCollapse, collapseInfo);
DoDebugChecks();
retVal = ProcessResult.Ok_Collapsed;
}
skip_to_end:
end_collapse();
return(retVal);
}
/// <summary>
/// Check if this m2 is the same as this mesh. By default only checks
/// vertices and triangles, turn on other parameters w/ flags
/// </summary>
public bool IsSameMesh(DMesh3 m2, bool bCheckEdges = false,
bool bCheckNormals = false, bool bCheckColors = false, bool bCheckUVs = false,
bool bCheckGroups = false,
float Epsilon = MathUtil.Epsilonf)
{
if (VertexCount != m2.VertexCount)
{
return(false);
}
if (TriangleCount != m2.TriangleCount)
{
return(false);
}
foreach (int vid in VertexIndices())
{
if (m2.IsVertex(vid) == false || GetVertex(vid).EpsilonEqual(m2.GetVertex(vid), Epsilon) == false)
{
return(false);
}
}
foreach (int tid in TriangleIndices())
{
if (m2.IsTriangle(tid) == false || GetTriangle(tid).Equals(m2.GetTriangle(tid)) == false)
{
return(false);
}
}
if (bCheckEdges)
{
if (EdgeCount != m2.EdgeCount)
{
return(false);
}
foreach (int eid in EdgeIndices())
{
if (m2.IsEdge(eid) == false || GetEdge(eid).Equals(m2.GetEdge(eid)) == false)
{
return(false);
}
}
}
if (bCheckNormals)
{
if (HasVertexNormals != m2.HasVertexNormals)
{
return(false);
}
if (HasVertexNormals)
{
foreach (int vid in VertexIndices())
{
if (GetVertexNormal(vid).EpsilonEqual(m2.GetVertexNormal(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckColors)
{
if (HasVertexColors != m2.HasVertexColors)
{
return(false);
}
if (HasVertexColors)
{
foreach (int vid in VertexIndices())
{
if (GetVertexColor(vid).EpsilonEqual(m2.GetVertexColor(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckUVs)
{
if (HasVertexUVs != m2.HasVertexUVs)
{
return(false);
}
if (HasVertexUVs)
{
foreach (int vid in VertexIndices())
{
if (GetVertexUV(vid).EpsilonEqual(m2.GetVertexUV(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckGroups)
{
if (HasTriangleGroups != m2.HasTriangleGroups)
{
return(false);
}
if (HasTriangleGroups)
{
foreach (int tid in TriangleIndices())
{
if (GetTriangleGroup(tid) != m2.GetTriangleGroup(tid))
{
return(false);
}
}
}
}
return(true);
}
protected virtual ProcessResult ProcessEdge(int edgeID)
{
RuntimeDebugCheck(edgeID);
EdgeConstraint constraint =
(constraints == null) ? EdgeConstraint.Unconstrained : constraints.GetEdgeConstraint(edgeID);
if (constraint.NoModifications)
{
return(ProcessResult.Ignored_EdgeIsFullyConstrained);
}
// look up verts and tris for this edge
int a = 0, b = 0, t0 = 0, t1 = 0;
if (mesh.GetEdge(edgeID, ref a, ref b, ref t0, ref t1) == false)
{
return(ProcessResult.Failed_NotAnEdge);
}
bool bIsBoundaryEdge = (t1 == DMesh3.InvalidID);
// look up 'other' verts c (from t0) and d (from t1, if it exists)
Index3i T0tv = mesh.GetTriangle(t0);
int c = IndexUtil.find_tri_other_vtx(a, b, T0tv);
Index3i T1tv = (bIsBoundaryEdge) ? DMesh3.InvalidTriangle : mesh.GetTriangle(t1);
int d = (bIsBoundaryEdge) ? DMesh3.InvalidID : IndexUtil.find_tri_other_vtx(a, b, T1tv);
Vector3d vA = mesh.GetVertex(a);
Vector3d vB = mesh.GetVertex(b);
double edge_len_sqr = (vA - vB).LengthSquared;
begin_collapse();
// check if we should collapse, and also find which vertex we should collapse to,
// in cases where we have constraints/etc
int collapse_to = -1;
bool bCanCollapse = EnableCollapses &&
constraint.CanCollapse &&
edge_len_sqr < MinEdgeLength * MinEdgeLength &&
can_collapse_constraints(edgeID, a, b, c, d, t0, t1, out collapse_to);
// optimization: if edge cd exists, we cannot collapse or flip. look that up here?
// funcs will do it internally...
// (or maybe we can collapse if cd exists? edge-collapse doesn't check for it explicitly...)
// if edge length is too short, we want to collapse it
bool bTriedCollapse = false;
if (bCanCollapse)
{
int iKeep = b, iCollapse = a;
Vector3d vNewPos = (vA + vB) * 0.5;
// if either vtx is fixed, collapse to that position
if (collapse_to == b)
{
vNewPos = vB;
}
else if (collapse_to == a)
{
iKeep = a; iCollapse = b;
vNewPos = vA;
}
else
{
vNewPos = get_projected_collapse_position(iKeep, vNewPos);
}
// TODO be smart about picking b (keep vtx).
// - swap if one is bdry vtx, for example?
// lots of cases where we cannot collapse, but we should just let
// mesh sort that out, right?
COUNT_COLLAPSES++;
DMesh3.EdgeCollapseInfo collapseInfo;
MeshResult result = mesh.CollapseEdge(iKeep, iCollapse, out collapseInfo);
if (result == MeshResult.Ok)
{
mesh.SetVertex(iKeep, vNewPos);
if (constraints != null)
{
constraints.ClearEdgeConstraint(edgeID);
constraints.ClearEdgeConstraint(collapseInfo.eRemoved0);
if (collapseInfo.eRemoved1 != DMesh3.InvalidID)
{
constraints.ClearEdgeConstraint(collapseInfo.eRemoved1);
}
constraints.ClearVertexConstraint(iCollapse);
}
OnEdgeCollapse(edgeID, iKeep, iCollapse, collapseInfo);
DoDebugChecks();
return(ProcessResult.Ok_Collapsed);
}
else
{
bTriedCollapse = true;
}
}
end_collapse();
begin_flip();
// if this is not a boundary edge, maybe we want to flip
bool bTriedFlip = false;
if (EnableFlips && constraint.CanFlip && bIsBoundaryEdge == false)
{
// don't want to flip if it will invert triangle...tetrahedron sign??
// can we do this more efficiently somehow?
bool a_is_boundary_vtx = (MeshIsClosed) ? false : (bIsBoundaryEdge || mesh.vertex_is_boundary(a));
bool b_is_boundary_vtx = (MeshIsClosed) ? false : (bIsBoundaryEdge || mesh.vertex_is_boundary(b));
bool c_is_boundary_vtx = (MeshIsClosed) ? false : mesh.vertex_is_boundary(c);
bool d_is_boundary_vtx = (MeshIsClosed) ? false : mesh.vertex_is_boundary(d);
int valence_a = mesh.GetVtxEdgeCount(a), valence_b = mesh.GetVtxEdgeCount(b);
int valence_c = mesh.GetVtxEdgeCount(c), valence_d = mesh.GetVtxEdgeCount(d);
int valence_a_target = (a_is_boundary_vtx) ? valence_a : 6;
int valence_b_target = (b_is_boundary_vtx) ? valence_b : 6;
int valence_c_target = (c_is_boundary_vtx) ? valence_c : 6;
int valence_d_target = (d_is_boundary_vtx) ? valence_d : 6;
// if total valence error improves by flip, we want to do it
int curr_err = Math.Abs(valence_a - valence_a_target) + Math.Abs(valence_b - valence_b_target)
+ Math.Abs(valence_c - valence_c_target) + Math.Abs(valence_d - valence_d_target);
int flip_err = Math.Abs((valence_a - 1) - valence_a_target) + Math.Abs((valence_b - 1) - valence_b_target)
+ Math.Abs((valence_c + 1) - valence_c_target) + Math.Abs((valence_d + 1) - valence_d_target);
if (flip_err < curr_err)
{
// try flip
DMesh3.EdgeFlipInfo flipInfo;
COUNT_FLIPS++;
MeshResult result = mesh.FlipEdge(edgeID, out flipInfo);
if (result == MeshResult.Ok)
{
DoDebugChecks();
return(ProcessResult.Ok_Flipped);
}
else
{
bTriedFlip = true;
}
}
}
end_flip();
begin_split();
// if edge length is too long, we want to split it
bool bTriedSplit = false;
if (EnableSplits && constraint.CanSplit && edge_len_sqr > MaxEdgeLength * MaxEdgeLength)
{
DMesh3.EdgeSplitInfo splitInfo;
COUNT_SPLITS++;
MeshResult result = mesh.SplitEdge(edgeID, out splitInfo);
if (result == MeshResult.Ok)
{
update_after_split(edgeID, a, b, splitInfo);
OnEdgeSplit(edgeID, a, b, splitInfo);
DoDebugChecks();
return(ProcessResult.Ok_Split);
}
else
{
bTriedSplit = true;
}
}
end_split();
if (bTriedFlip || bTriedSplit || bTriedCollapse)
{
return(ProcessResult.Failed_OpNotSuccessful);
}
else
{
return(ProcessResult.Ignored_EdgeIsFine);
}
}
/// <summary>
/// Stitch two sets of boundary edges that are provided as unordered pairs of edges, by
/// adding triangulated quads between each edge pair.
/// If a failure is encountered during stitching, the triangles added up to that point are removed.
/// </summary>
public virtual int[] StitchUnorderedEdges(List <Index2i> EdgePairs, int group_id = -1)
{
int N = EdgePairs.Count;
int[] new_tris = new int[N * 2];
int i = 0;
for (; i < N; ++i)
{
Index2i edges = EdgePairs[i];
// look up and orient the first edge
Index4i edge_a = Mesh.GetEdge(edges.a);
if (edge_a.d != DMesh3.InvalidID)
{
goto operation_failed;
}
Index3i edge_a_tri = Mesh.GetTriangle(edge_a.c);
int a = edge_a.a, b = edge_a.b;
IndexUtil.orient_tri_edge(ref a, ref b, edge_a_tri);
// look up and orient the second edge
Index4i edge_b = Mesh.GetEdge(edges.b);
if (edge_b.d != DMesh3.InvalidID)
{
goto operation_failed;
}
Index3i edge_b_tri = Mesh.GetTriangle(edge_b.c);
int c = edge_b.a, d = edge_b.b;
IndexUtil.orient_tri_edge(ref c, ref d, edge_b_tri);
// swap second edge (right? should this be a parameter?)
int tmp = c; c = d; d = tmp;
Index3i t1 = new Index3i(b, a, d);
Index3i t2 = new Index3i(a, c, d);
int tid1 = Mesh.AppendTriangle(t1, group_id);
int tid2 = Mesh.AppendTriangle(t2, group_id);
if (tid1 == DMesh3.InvalidID || tid2 == DMesh3.InvalidID)
{
goto operation_failed;
}
new_tris[2 * i] = tid1;
new_tris[2 * i + 1] = tid2;
}
return(new_tris);
operation_failed:
// remove what we added so far
if (i > 0)
{
if (remove_triangles(new_tris, 2 * (i - 1)) == false)
{
throw new Exception("MeshConstructor.StitchLoop: failed to add all triangles, and also failed to back out changes.");
}
}
return(null);
}
/// <summary>
/// Stitch two sets of boundary edges that are provided as unordered pairs of edges, by
/// adding triangulated quads between each edge pair.
/// If bAbortOnFailure==true and a failure is encountered during stitching, the triangles added up to that point are removed.
/// If bAbortOnFailure==false, failures are ignored and the returned triangle list may contain invalid values!
/// </summary>
public virtual int[] StitchUnorderedEdges(List <Index2i> EdgePairs, int group_id, bool bAbortOnFailure, out bool stitch_incomplete)
{
int N = EdgePairs.Count;
int[] new_tris = new int[N * 2];
if (bAbortOnFailure == false)
{
for (int k = 0; k < new_tris.Length; ++k)
{
new_tris[k] = DMesh3.InvalidID;
}
}
stitch_incomplete = false;
int i = 0;
for (; i < N; ++i)
{
Index2i edges = EdgePairs[i];
// look up and orient the first edge
Index4i edge_a = Mesh.GetEdge(edges.a);
if (edge_a.d != DMesh3.InvalidID)
{
if (bAbortOnFailure)
{
goto operation_failed;
}
else
{
stitch_incomplete = true; continue;
}
}
Index3i edge_a_tri = Mesh.GetTriangle(edge_a.c);
int a = edge_a.a, b = edge_a.b;
IndexUtil.orient_tri_edge(ref a, ref b, edge_a_tri);
// look up and orient the second edge
Index4i edge_b = Mesh.GetEdge(edges.b);
if (edge_b.d != DMesh3.InvalidID)
{
if (bAbortOnFailure)
{
goto operation_failed;
}
else
{
stitch_incomplete = true; continue;
}
}
Index3i edge_b_tri = Mesh.GetTriangle(edge_b.c);
int c = edge_b.a, d = edge_b.b;
IndexUtil.orient_tri_edge(ref c, ref d, edge_b_tri);
// swap second edge (right? should this be a parameter?)
int tmp = c; c = d; d = tmp;
var t1 = new Index3i(b, a, d);
var t2 = new Index3i(a, c, d);
int tid1 = Mesh.AppendTriangle(t1, group_id);
int tid2 = Mesh.AppendTriangle(t2, group_id);
if (tid1 < 0 || tid2 < 0)
{
if (bAbortOnFailure)
{
goto operation_failed;
}
else
{
stitch_incomplete = true; continue;
}
}
new_tris[2 * i] = tid1;
new_tris[2 * i + 1] = tid2;
}
return(new_tris);
operation_failed:
// remove what we added so far
if (i > 0)
{
if (remove_triangles(new_tris, 2 * (i - 1)) == false)
{
throw new Exception("MeshEditor.StitchLoop: failed to add all triangles, and also failed to back out changes.");
}
}
return(null);
}
/// <summary>
/// Check if this m2 is the same as this mesh. By default only checks
/// vertices and triangles, turn on other parameters w/ flags
/// </summary>
public bool IsSameMesh(DMesh3 m2, bool bCheckConnectivity, bool bCheckEdgeIDs = false,
bool bCheckNormals = false, bool bCheckColors = false, bool bCheckUVs = false,
bool bCheckGroups = false,
float Epsilon = MathUtil.Epsilonf)
{
if (VertexCount != m2.VertexCount)
{
return(false);
}
if (TriangleCount != m2.TriangleCount)
{
return(false);
}
foreach (int vid in VertexIndices())
{
if (m2.IsVertex(vid) == false || GetVertex(vid).EpsilonEqual(m2.GetVertex(vid), Epsilon) == false)
{
return(false);
}
}
foreach (int tid in TriangleIndices())
{
if (m2.IsTriangle(tid) == false || GetTriangle(tid).Equals(m2.GetTriangle(tid)) == false)
{
return(false);
}
}
if (bCheckConnectivity)
{
foreach (int eid in EdgeIndices())
{
Index4i e = GetEdge(eid);
int other_eid = m2.FindEdge(e.a, e.b);
if (other_eid == InvalidID)
{
return(false);
}
Index4i oe = m2.GetEdge(other_eid);
if (Math.Min(e.c, e.d) != Math.Min(oe.c, oe.d) || Math.Max(e.c, e.d) != Math.Max(oe.c, oe.d))
{
return(false);
}
}
}
if (bCheckEdgeIDs)
{
if (EdgeCount != m2.EdgeCount)
{
return(false);
}
foreach (int eid in EdgeIndices())
{
if (m2.IsEdge(eid) == false || GetEdge(eid).Equals(m2.GetEdge(eid)) == false)
{
return(false);
}
}
}
if (bCheckNormals)
{
if (HasVertexNormals != m2.HasVertexNormals)
{
return(false);
}
if (HasVertexNormals)
{
foreach (int vid in VertexIndices())
{
if (GetVertexNormal(vid).EpsilonEqual(m2.GetVertexNormal(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckColors)
{
if (HasVertexColors != m2.HasVertexColors)
{
return(false);
}
if (HasVertexColors)
{
foreach (int vid in VertexIndices())
{
if (GetVertexColor(vid).EpsilonEqual(m2.GetVertexColor(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckUVs)
{
if (HasVertexUVs != m2.HasVertexUVs)
{
return(false);
}
if (HasVertexUVs)
{
foreach (int vid in VertexIndices())
{
if (GetVertexUV(vid).EpsilonEqual(m2.GetVertexUV(vid), Epsilon) == false)
{
return(false);
}
}
}
}
if (bCheckGroups)
{
if (HasTriangleGroups != m2.HasTriangleGroups)
{
return(false);
}
if (HasTriangleGroups)
{
foreach (int tid in TriangleIndices())
{
if (GetTriangleGroup(tid) != m2.GetTriangleGroup(tid))
{
return(false);
}
}
}
}
return(true);
}