/// <summary>
/// Merge any positions in the <see cref="PositionCollection"/> of the
/// specified mesh that are at a distance less than the specified tolerance
/// from each other.
/// </summary>
/// <param name="mesh">Mesh to be processed.</param>
/// <param name="tolerance">Tolerance value that determines how close
/// positions must be to each other to be merged.</param>
/// <remarks>
/// This method will also update the <see cref="VertexContent.PositionIndices"/>
/// in the <see cref="GeometryContent"/> of the specified mesh.
/// </remarks>
public static void MergeDuplicatePositions(MeshContent mesh, float tolerance)
{
if (mesh == null)
{
throw new ArgumentNullException("mesh");
}
// TODO Improve performance with spatial partitioning scheme
var indexLists = new List <IndexUpdateList>();
foreach (var geom in mesh.Geometry)
{
var list = new IndexUpdateList(geom.Vertices.PositionIndices);
indexLists.Add(list);
}
for (var i = mesh.Positions.Count - 1; i >= 1; i--)
{
var pi = mesh.Positions[i];
for (var j = i - 1; j >= 0; j--)
{
var pj = mesh.Positions[j];
if (Vector3.Distance(pi, pj) <= tolerance)
{
foreach (var list in indexLists)
{
list.Update(i, j);
}
mesh.Positions.RemoveAt(i);
}
}
}
}
/// <summary>
/// Merge vertices with the same <see cref="VertexContent.PositionIndices"/> and
/// <see cref="VertexChannel"/> data within the specified
/// <see cref="GeometryContent"/>.
/// </summary>
/// <param name="geometry">Geometry to be processed.</param>
public static void MergeDuplicateVertices(GeometryContent geometry)
{
if (geometry == null)
{
throw new ArgumentNullException("geometry");
}
var verts = geometry.Vertices;
var hashMap = new Dictionary <int, List <VertexData> >();
var indices = new IndexUpdateList(geometry.Indices);
var vIndex = 0;
for (var i = 0; i < geometry.Indices.Count; i++)
{
var iIndex = geometry.Indices[i];
var iData = new VertexData
{
Index = iIndex,
PositionIndex = verts.PositionIndices[vIndex],
ChannelData = new object[verts.Channels.Count]
};
for (var channel = 0; channel < verts.Channels.Count; channel++)
{
iData.ChannelData[channel] = verts.Channels[channel][vIndex];
}
var hash = iData.ComputeHash();
var merged = false;
List <VertexData> candidates;
if (hashMap.TryGetValue(hash, out candidates))
{
for (var candidateIndex = 0; candidateIndex < candidates.Count; candidateIndex++)
{
var c = candidates[candidateIndex];
if (!iData.ContentEquals(c))
{
continue;
}
// Match! Update the corresponding indices and remove the vertex
indices.Update(iIndex, c.Index);
verts.RemoveAt(vIndex);
merged = true;
}
if (!merged)
{
candidates.Add(iData);
}
}
else
{
// no vertices with the same hash yet, create a new list for the data
hashMap.Add(hash, new List <VertexData> {
iData
});
}
if (!merged)
{
vIndex++;
}
}
// update the indices because of the vertices we removed
indices.Pack();
}