private void ConvertMeshes(List <Mesh> meshes, VertexPositionBuffer positionBuffer, VertexNormalBuffer normalBuffer, VertexColorBuffer colorBuffer, VertexUVBuffer uvBuffer)
{
var state = new MeshRenderState();
for (var i = 0; i < meshes.Count; i++)
{
var mesh = meshes[i];
if (mesh.Parameters != null && mesh.Parameters.Count > 0)
{
ProcessMeshParameters(mesh.Parameters, ref state);
}
var stateCopy = state;
stateCopy.TextureId = 0;
stateCopy.TileMode = 0;
//stateCopy.IndexFlags = 0;
stateCopy.AmbientColor = new Color();
sUniqueStates.Add(stateCopy);
var aiMesh = new Assimp.Mesh();
var vertexCache = new List <Vertex>();
Debug.Assert(state.IndexFlags.HasFlag(IndexAttributeFlags.HasPosition) ? positionBuffer != null : true);
Debug.Assert(state.IndexFlags.HasFlag(IndexAttributeFlags.HasNormal) ? normalBuffer != null : true);
Debug.Assert(state.IndexFlags.HasFlag(IndexAttributeFlags.HasColor) ? colorBuffer != null : true);
Debug.Assert(state.IndexFlags.HasFlag(IndexAttributeFlags.HasUV) ? uvBuffer != null : true);
// Extract all vertices used by the triangles, and build a new vertex list
// with each vertex attribute clumped together
var aiFace = new Assimp.Face();
foreach (var index in mesh.DisplayLists.SelectMany(x => x.ToTriangles()))
{
var vertex = new Vertex();
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasPosition))
{
vertex.Position = positionBuffer.Elements[index.PositionIndex];
}
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasNormal))
{
vertex.Normal = normalBuffer.Elements[index.NormalIndex];
}
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasColor))
{
vertex.Color = colorBuffer.Elements[index.ColorIndex];
}
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasUV))
{
vertex.UV = uvBuffer.Elements[index.UVIndex];
}
// Find index of this vertex in the list in case it already exists
var vertexIndex = vertexCache.IndexOf(vertex);
if (vertexIndex == -1)
{
vertexIndex = vertexCache.Count;
vertexCache.Add(vertex);
}
aiFace.Indices.Add(vertexIndex);
if (aiFace.IndexCount == 3)
{
// Done with this face, move on to the next one
aiMesh.Faces.Add(aiFace);
aiFace = new Assimp.Face();
}
}
// Convert vertices
aiMesh.Vertices.AddRange(vertexCache.Select(x => ToAssimp(x.Position)));
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasNormal))
{
aiMesh.Normals.AddRange(vertexCache.Select(x => ToAssimp(x.Normal)));
}
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasUV))
{
aiMesh.TextureCoordinateChannels[0].AddRange(vertexCache.Select(x => ToAssimp(UVCodec.Decode1023(x.UV))));
}
if (state.IndexFlags.HasFlag(IndexAttributeFlags.HasColor))
{
aiMesh.VertexColorChannels[0].AddRange(vertexCache.Select(x => ToAssimp(x.Color)));
}
// Convert material
if (!mConvertedMaterialCache.TryGetValue(state, out var aiMaterialIndex))
{
// Not in cache, so create a new one and add it
aiMaterialIndex = Scene.MaterialCount;
Scene.Materials.Add(CreateMaterial(Color.Gray, Color.Gray, Color.Gray, FormatTextureName(state.TextureId), false, false,
state.TileMode.HasFlag(TileMode.MirrorU),
state.TileMode.HasFlag(TileMode.MirrorV),
state.BlendAlphaFlags.HasFlag(BlendAlphaFlags.UseAlpha)));
mConvertedMaterialCache[state] = aiMaterialIndex;
}
aiMesh.MaterialIndex = aiMaterialIndex;
// Add mesh to scene.
Scene.Meshes.Add(aiMesh);
}
}
private void ReadVertexAttributes(EndianBinaryReader reader)
{
VertexBuffers = new List <VertexAttributeBuffer>();
while (true)
{
var type = ( VertexAttributeType )reader.ReadByte();
if (type == VertexAttributeType.End)
{
break;
}
var elementSize = reader.ReadByte();
var elementCount = reader.ReadUInt16();
var field04 = reader.ReadInt32();
var dataOffset = reader.ReadUInt32();
var dataSize = reader.ReadUInt32();
VertexAttributeBuffer buffer;
switch (type)
{
case VertexAttributeType.Position:
case VertexAttributeType.Normal:
{
Vector3[] elements = null;
reader.ReadAtOffset(dataOffset, () => elements = reader.ReadVector3s(elementCount));
if (type == VertexAttributeType.Position)
{
buffer = new VertexPositionBuffer(elements);
}
else
{
buffer = new VertexNormalBuffer(elements);
}
}
break;
case VertexAttributeType.Color:
{
Color[] elements = null;
reader.ReadAtOffset(dataOffset, () =>
{
var endianness = reader.Endianness;
reader.Endianness = Endianness.Big;
elements = reader.ReadColors(elementCount);
reader.Endianness = endianness;
});
buffer = new VertexColorBuffer(elements);
}
break;
case VertexAttributeType.UV:
{
Vector2 <short>[] elements = null;
reader.ReadAtOffset(dataOffset, () => elements = reader.ReadVector2Int16s(elementCount));
buffer = new VertexUVBuffer(elements);
}
break;
default:
throw new InvalidGeometryDataException($"Attempted to read invalid/unknown vertex attribute: {type}");
}
Debug.Assert(elementSize == buffer.ElementSize);
Debug.Assert(elementCount == buffer.ElementCount);
Debug.Assert(field04 == buffer.Field04);
Debug.Assert(dataSize == buffer.DataSize);
VertexBuffers.Add(buffer);
}
}