/// <summary>
/// Export the HMesh as a number of meshes, split into a number of subregions.
/// If the parameter used material is provided, the mesh only contains submeshes with geometry and the submesh index
/// is added to the used material.
/// Is a mesh does not contain any vertices it is skipped.
/// </summary>
public List <Mesh> ExportSplit(Vector3i axisSplit, List <List <int> > usedMaterials = null, double sharpEdgeAngle = 360)
{
var bounds = ComputeBoundsD();
bounds.extents += Vector3D.one * 0.000001; // add delta size to ensure no vertex is on bounds
var resList = new List <Mesh>();
// Enumerate vertices
for (int i = 0; i < vertices.Count; i++)
{
vertices[i].label = i;
}
var maxFaceLabel = 0;
foreach (var face in faces)
{
maxFaceLabel = Mathf.Max(maxFaceLabel, face.label);
}
int clusterCount = 0;
MarkSharpEdges(sharpEdgeAngle);
var faceClusters = SeparateMeshByGeometry(out clusterCount);
Debug.Log("Face clusters: " + clusterCount);
var remap = new int[vertices.Count];
for (var i = 0; i < axisSplit[0]; i++)
{
double minX = bounds.min.x + i * (bounds.size.x / axisSplit[0]);
double maxX = bounds.min.x + (i + 1) * (bounds.size.x / axisSplit[0]);
for (var j = 0; j < axisSplit[1]; j++)
{
double minY = bounds.min.y + j * (bounds.size.y / axisSplit[1]);
double maxY = bounds.min.y + (j + 1) * (bounds.size.y / axisSplit[1]);
for (var k = 0; k < axisSplit[2]; k++)
{
double minZ = bounds.min.z + k * (bounds.size.z / axisSplit[2]);
double maxZ = bounds.min.z + (k + 1) * (bounds.size.z / axisSplit[2]);
// DebugExt.DrawBox(new Vector3D(minX, minY, minZ).ToVector3(), new Vector3D(maxX, maxY, maxZ).ToVector3(),Color.white, 10);
var min = new Vector3D(minX, minY, minZ);
var max = new Vector3D(maxX, maxY, maxZ);
var res = new Mesh();
res.name = "HMesh_" + i + "," + j + "," + k;
var vertexArray = new List <Vector3>();
var normalArray = new List <Vector3>();
var uv1 = new List <Vector2>();
var uv2 = new List <Vector2>();
res.subMeshCount = maxFaceLabel + 1;
List <Face> facesInRegion = new List <Face>();
foreach (var face in faces)
{
var center = face.GetCenter();
if (Vector3D.AllLessThan(min, center) && Vector3D.AllLessEqualThan(center, max))
{
facesInRegion.Add(face);
}
}
var triangles = new List <List <int> >();
for (int ii = 0; ii <= maxFaceLabel; ii++)
{
triangles.Add(new List <int>());
}
for (int clusterIndex = 0; clusterIndex < clusterCount; clusterIndex++)
{
// clear remap
for (int x = 0; x < remap.Length; x++)
{
remap[x] = -1;
}
for (var faceLabel = 0; faceLabel <= maxFaceLabel; faceLabel++)
{
foreach (var face in facesInRegion)
{
if (faceClusters[face.id] != clusterIndex)
{
continue;
}
if (face.label == faceLabel)
{
if (face.NoEdges() != 3)
{
Debug.LogError("Only triangles supported. Was " + face.NoEdges() + "-gon");
continue;
}
var he = face.halfedge;
var first = true;
while (he != face.halfedge || first)
{
var indexOfVertex = he.vert.label;
var indexOfVertexRemapped = remap[indexOfVertex];
if (indexOfVertexRemapped == -1)
{
indexOfVertexRemapped = vertexArray.Count;
remap[indexOfVertex] = indexOfVertexRemapped;
vertexArray.Add(vertices[indexOfVertex].position);
uv1.Add(vertices[indexOfVertex].uv1);
uv2.Add(vertices[indexOfVertex].uv2);
// compute normal
Vector3D n = Vector3D.zero;
int count = 0;
foreach (var vertHe in he.vert.CirculateAllIngoing())
{
if (faceClusters[vertHe.face.id] == clusterIndex)
{
double angle = Vector3D.Angle(-vertHe.GetDirection(), vertHe.next.GetDirection());
n += angle * vertHe.face.GetNormal();
count++;
}
}
if (n.sqrMagnitude <= 0 || double.IsNaN(Vector3D.Dot(n, n)))
{
Debug.LogWarning("Cannot compute normal n is " + n.ToString("R") + " edges of vertex " + he.vert.Circulate().Count + " same cluster " + count + " " + he.face.ToString());
foreach (var vertHe in he.vert.CirculateAllIngoing())
{
if (faceClusters[vertHe.face.id] == clusterIndex)
{
Debug.Log(vertHe.face.ToString());
}
}
n = new Vector3D(0, 1, 0);
}
else
{
n.Normalize();
}
normalArray.Add(n.ToVector3());
}
triangles[faceLabel].Add(indexOfVertexRemapped);
he = he.next;
first = false;
}
}
}
}
}
if (vertexArray.Count == 0)
{
// empty mesh - skip
continue;
}
resList.Add(res);
if (vertexArray.Count > 65000)
{
Debug.LogWarning("Vertex count was " + vertexArray.Count);
}
res.vertices = vertexArray.ToArray();
res.uv = uv1.ToArray();
res.uv2 = uv2.ToArray();
res.normals = normalArray.ToArray();
// add mesh indices
// if usedMaterials exists then filter out any empty submesh
List <int> materialIndices = null;
if (usedMaterials != null)
{
materialIndices = new List <int>();
usedMaterials.Add(materialIndices);
}
for (int ii = 0; ii < triangles.Count; ii++)
{
if (materialIndices != null)
{
if (triangles[ii].Count > 0)
{
res.SetIndices(triangles[ii].ToArray(), MeshTopology.Triangles, materialIndices.Count, true);
materialIndices.Add(ii);
}
}
else
{
res.SetIndices(triangles[ii].ToArray(), MeshTopology.Triangles, ii, true);
}
}
res.RecalculateBounds();
}
}
}
return(resList);
}