public static List <BrepTrim> _SortByCrvs3d(this BrepTrimList trims, out List <bool> trimsReversedFlag, out bool crvs3dHasReversedDirection)
{
var reversedDirectionCount = 0;
trimsReversedFlag = new List <bool>();
var trimsUnsorted = trims._SelectNonSingularTrims();
var trimsSorted = new List <BrepTrim>();
var searchForIndex = -1;
//var debugIndexes = new List<int>();
//var debugIs = new List<int>();
while (trimsUnsorted.Count > 0)
{
bool found = false;
int foundIndex = 0;
for (var i = 0; i < trimsUnsorted.Count; i++)
{
var trim = trimsUnsorted[i];
//var indexStart = trim.Edge.PointAtStart._GetVertexIndex(trim.Brep.Vertices);
//var indexEnd = trim.Edge.PointAtEnd._GetVertexIndex(trim.Brep.Vertices);
var indexStart = trim.Edge._GetStartVertex().VertexIndex;
var indexEnd = trim.Edge._GetEndVertex().VertexIndex;
if (searchForIndex == -1)
{
searchForIndex = indexStart;
}
if (!found && (indexStart == searchForIndex || indexEnd == searchForIndex))
{
found = true;
foundIndex = i;
// continue to search for circular crvs - that PointStart == PointEnd
}
if (indexStart == searchForIndex && indexStart == indexEnd)
{
found = true;
foundIndex = i;
break; //if found circular crv stop search - circular crvs have the highest priority
}
}
if (found)
{
var trim = trimsUnsorted[foundIndex];
var indexStart = trim.Edge._GetStartVertex().VertexIndex;
var indexEnd = trim.Edge._GetEndVertex().VertexIndex;
var distToStart = trim.Edge.PointAtStart._DistanceTo(trim.Face.PointAt(trim.PointAtStart.X, trim.PointAtStart.Y));
var distToEnd = trim.Edge.PointAtStart._DistanceTo(trim.Face.PointAt(trim.PointAtEnd.X, trim.PointAtEnd.Y));
if (distToStart < distToEnd)
{
reversedDirectionCount--;
}
if (distToStart > distToEnd)
{
reversedDirectionCount++;
}
//debugIndexes.Add(indexStart);
//debugIndexes.Add(indexEnd);
trimsUnsorted.RemoveAt(foundIndex);
//debugIs.Add(foundIndex);
trimsSorted.Add(trim);
// Detect reversed flag: a) end->start - straight connection b)end->end - reversed connection
var straightConnection = (indexStart == searchForIndex);
// for circular crvs simple detection if connection is staight doesnt work - so lets do precision calculation
if (indexStart == indexEnd)
{
}
if (straightConnection)
{
trimsReversedFlag.Add(false);
searchForIndex = indexEnd;
}
else
{
trimsReversedFlag.Add(true);
searchForIndex = indexStart;
}
}
if (!found)
{
throw new Exception(
"Exception: Cannot find next trim! (Issue_SurfaceBad_BadTrim_Singular.SortTrims)");
}
}
crvs3dHasReversedDirection = reversedDirectionCount > 0;
return(trimsSorted);
}
