// OnPolymesh is called when a tessellated polymesh of a 3D face is being output.
// The current material is applied to the polymesh.
public void OnPolymesh(
PolymeshTopology InPolymeshNode // tessellated polymesh output node
)
{
if (IgnoreElementGeometry())
{
return;
}
// Retrieve the Datasmith mesh being processed.
FDatasmithFacadeMesh CurrentMesh = GetCurrentMesh();
Transform MeshPointsTransform = GetCurrentMeshPointsTransform();
// Retrieve the index of the current material and make the Datasmith mesh keep track of it.
int CurrentMaterialIndex = GetCurrentMaterialIndex();
int initialVertexCount = CurrentMesh.GetVertexCount();
// Add the vertex points (in right-handed Z-up coordinates) to the Datasmith mesh.
foreach (XYZ Point in InPolymeshNode.GetPoints())
{
XYZ FinalPoint = MeshPointsTransform != null?MeshPointsTransform.OfPoint(Point) : Point;
CurrentMesh.AddVertex((float)FinalPoint.X, (float)FinalPoint.Y, (float)FinalPoint.Z);
}
// Add the vertex UV texture coordinates to the Datasmith mesh.
foreach (UV uv in InPolymeshNode.GetUVs())
{
CurrentMesh.AddUV(0, (float)uv.U, (float)-uv.V);
}
IList <PolymeshFacet> Facets = InPolymeshNode.GetFacets();
// Add the triangle vertex indexes to the Datasmith mesh.
foreach (PolymeshFacet facet in Facets)
{
CurrentMesh.AddTriangle(initialVertexCount + facet.V1, initialVertexCount + facet.V2, initialVertexCount + facet.V3, CurrentMaterialIndex);
}
// Add the triangle vertex normals (in right-handed Z-up coordinates) to the Datasmith mesh.
// Normals can be associated with either points or facets of the polymesh.
switch (InPolymeshNode.DistributionOfNormals)
{
case DistributionOfNormals.AtEachPoint:
{
IList <XYZ> normals = InPolymeshNode.GetNormals();
if (MeshPointsTransform != null)
{
foreach (PolymeshFacet facet in Facets)
{
XYZ normal1 = MeshPointsTransform.OfVector(normals[facet.V1]);
XYZ normal2 = MeshPointsTransform.OfVector(normals[facet.V2]);
XYZ normal3 = MeshPointsTransform.OfVector(normals[facet.V3]);
CurrentMesh.AddNormal((float)normal1.X, (float)normal1.Y, (float)normal1.Z);
CurrentMesh.AddNormal((float)normal2.X, (float)normal2.Y, (float)normal2.Z);
CurrentMesh.AddNormal((float)normal3.X, (float)normal3.Y, (float)normal3.Z);
}
}
else
{
foreach (PolymeshFacet facet in Facets)
{
XYZ normal1 = normals[facet.V1];
XYZ normal2 = normals[facet.V2];
XYZ normal3 = normals[facet.V3];
CurrentMesh.AddNormal((float)normal1.X, (float)normal1.Y, (float)normal1.Z);
CurrentMesh.AddNormal((float)normal2.X, (float)normal2.Y, (float)normal2.Z);
CurrentMesh.AddNormal((float)normal3.X, (float)normal3.Y, (float)normal3.Z);
}
}
break;
}
case DistributionOfNormals.OnePerFace:
{
XYZ normal = InPolymeshNode.GetNormals()[0];
if (MeshPointsTransform != null)
{
normal = MeshPointsTransform.OfVector(normal);
}
for (int i = 0; i < 3 * InPolymeshNode.NumberOfFacets; i++)
{
CurrentMesh.AddNormal((float)normal.X, (float)normal.Y, (float)normal.Z);
}
break;
}
case DistributionOfNormals.OnEachFacet:
{
if (MeshPointsTransform != null)
{
foreach (XYZ normal in InPolymeshNode.GetNormals())
{
XYZ FinalNormal = MeshPointsTransform.OfVector(normal);
CurrentMesh.AddNormal((float)FinalNormal.X, (float)FinalNormal.Y, (float)FinalNormal.Z);
CurrentMesh.AddNormal((float)FinalNormal.X, (float)FinalNormal.Y, (float)FinalNormal.Z);
CurrentMesh.AddNormal((float)FinalNormal.X, (float)FinalNormal.Y, (float)FinalNormal.Z);
}
}
else
{
foreach (XYZ normal in InPolymeshNode.GetNormals())
{
CurrentMesh.AddNormal((float)normal.X, (float)normal.Y, (float)normal.Z);
CurrentMesh.AddNormal((float)normal.X, (float)normal.Y, (float)normal.Z);
CurrentMesh.AddNormal((float)normal.X, (float)normal.Y, (float)normal.Z);
}
}
break;
}
}
}
public static void ParseMesh(FDatasmithFacadeMesh DatasmithMesh, List <Mesh> MeshSections, List <RhinoMaterialInfo> MaterialInfos)
{
int VertexIndexOffset = 0;
List <RhinoMaterialInfo> UniqueMaterialInfo = new List <RhinoMaterialInfo>();
for (int MeshIndex = 0; MeshIndex < MeshSections.Count; ++MeshIndex)
{
Mesh RhinoMesh = MeshSections[MeshIndex];
// Get Material index for the current section.
int MaterialIndex = UniqueMaterialInfo.FindIndex((CurrentInfo) => CurrentInfo == MaterialInfos[MeshIndex]);
if (MaterialIndex == -1)
{
MaterialIndex = UniqueMaterialInfo.Count;
DatasmithMesh.AddMaterial(MaterialIndex, MaterialInfos[MeshIndex]?.Name);
UniqueMaterialInfo.Add(MaterialInfos[MeshIndex]);
}
// Add all the section vertices to the mesh.
for (int VertexIndex = 0; VertexIndex < RhinoMesh.Vertices.Count; ++VertexIndex)
{
Point3f Vertex = RhinoMesh.Vertices[VertexIndex];
DatasmithMesh.AddVertex(Vertex.X, Vertex.Y, Vertex.Z);
}
// Try to compute normals if the section doesn't have them
if (RhinoMesh.Normals.Count == 0)
{
RhinoMesh.Normals.ComputeNormals();
}
bool bUseFaceNormals = RhinoMesh.Normals.Count != RhinoMesh.Vertices.Count && RhinoMesh.FaceNormals.Count == RhinoMesh.Faces.Count;
//Add triangles and normals to the mesh.
for (int FaceIndex = 0; FaceIndex < RhinoMesh.Faces.Count; ++FaceIndex)
{
MeshFace Face = RhinoMesh.Faces[FaceIndex];
DatasmithMesh.AddTriangle(VertexIndexOffset + Face.A, VertexIndexOffset + Face.B, VertexIndexOffset + Face.C, MaterialIndex);
if (Face.IsQuad)
{
DatasmithMesh.AddTriangle(VertexIndexOffset + Face.A, VertexIndexOffset + Face.C, VertexIndexOffset + Face.D, MaterialIndex);
}
if (bUseFaceNormals)
{
Vector3f Normal = RhinoMesh.FaceNormals[FaceIndex];
AddNormalsToMesh(DatasmithMesh, Normal);
if (Face.IsQuad)
{
AddNormalsToMesh(DatasmithMesh, Normal);
}
}
else
{
Vector3f[] Normals = new Vector3f[] { RhinoMesh.Normals[Face.A], RhinoMesh.Normals[Face.B], RhinoMesh.Normals[Face.C] };
AddNormalsToMesh(DatasmithMesh, Normals[0], Normals[1], Normals[2]);
if (Face.IsQuad)
{
Vector3f DNormal = RhinoMesh.Normals[Face.D];
AddNormalsToMesh(DatasmithMesh, Normals[0], Normals[2], DNormal);
}
}
}
// Add the UV coordinates for the triangles we just added.
int NumberOfUVCoord = RhinoMesh.TextureCoordinates.Count;
foreach (var UV in RhinoMesh.TextureCoordinates)
{
DatasmithMesh.AddUV(0, UV.X, 1 - UV.Y);
}
VertexIndexOffset += RhinoMesh.Vertices.Count;
}
}
