/// <summary>
/// Test the mesh for topological consistency.
/// </summary>
public static bool IsConsistent(Mesh mesh)
{
Otri tri = default(Otri);
Otri oppotri = default(Otri), oppooppotri = default(Otri);
Vertex org, dest, apex;
Vertex oppoorg, oppodest;
var logger = Log.Instance;
// Temporarily turn on exact arithmetic if it's off.
bool saveexact = Behavior.NoExact;
Behavior.NoExact = false;
int horrors = 0;
// Run through the list of triangles, checking each one.
foreach (var t in mesh.triangles)
{
tri.tri = t;
// Check all three edges of the triangle.
for (tri.orient = 0; tri.orient < 3; tri.orient++)
{
org = tri.Org();
dest = tri.Dest();
if (tri.orient == 0)
{
// Only test for inversion once.
// Test if the triangle is flat or inverted.
apex = tri.Apex();
if (predicates.CounterClockwise(org, dest, apex) <= 0.0)
{
if (Log.Verbose)
{
logger.Warning(String.Format("Triangle is flat or inverted (ID {0}).", t.id),
"MeshValidator.IsConsistent()");
}
horrors++;
}
}
// Find the neighboring triangle on this edge.
tri.Sym(ref oppotri);
if (oppotri.tri.id != Mesh.DUMMY)
{
// Check that the triangle's neighbor knows it's a neighbor.
oppotri.Sym(ref oppooppotri);
if ((tri.tri != oppooppotri.tri) || (tri.orient != oppooppotri.orient))
{
if (tri.tri == oppooppotri.tri && Log.Verbose)
{
logger.Warning("Asymmetric triangle-triangle bond: (Right triangle, wrong orientation)",
"MeshValidator.IsConsistent()");
}
horrors++;
}
// Check that both triangles agree on the identities
// of their shared vertices.
oppoorg = oppotri.Org();
oppodest = oppotri.Dest();
if ((org != oppodest) || (dest != oppoorg))
{
if (Log.Verbose)
{
logger.Warning("Mismatched edge coordinates between two triangles.",
"MeshValidator.IsConsistent()");
}
horrors++;
}
}
}
}
// Check for unconnected vertices
mesh.MakeVertexMap();
foreach (var v in mesh.vertices.Values)
{
if (v.tri.tri == null && Log.Verbose)
{
logger.Warning("Vertex (ID " + v.id + ") not connected to mesh (duplicate input vertex?)",
"MeshValidator.IsConsistent()");
}
}
// Restore the status of exact arithmetic.
Behavior.NoExact = saveexact;
return (horrors == 0);
}