/// <summary>
/// Converts all meshes in the given mesh array. Each mesh is split
/// up per material, the indices of the generated meshes are stored in
/// the node structure.
/// </summary>
/// <param name="scene">The scene to construct the return data in.</param>
/// <param name="node">The target node structure that references the constructed meshes.</param>
/// <param name="meshes">The array of meshes to convert</param>
protected void CreateMeshes(AssimpSharp.Scene scene, AssimpSharp.Node node, List<AssimpSharp.XFile.Mesh> meshes)
{
if (meshes.Count == 0)
{
return;
}
// create a mesh for each mesh-material combination in the source node
var result = new List<AssimpSharp.Mesh>();
for (int a = 0; a < meshes.Count; a++)
{
var sourceMesh = meshes[a];
// first convert its materials so that we can find them with their index afterwards
ConvertMaterials(scene, sourceMesh.Materials);
int numMaterials = Math.Max(sourceMesh.Materials.Count, 1);
for (int b = 0; b < numMaterials; b++)
{
// collect the faces belonging to this material
var faces = new List<int>();
var numVertices = 0;
if (sourceMesh.FaceMaterials.Count > 0)
{
// if there is a per-face material defined, select the faces with the corresponding material
for (int c = 0; c < sourceMesh.FaceMaterials.Count; c++)
{
if (sourceMesh.FaceMaterials[c] == b)
{
faces.Add(c);
numVertices += sourceMesh.PosFaces[c].Indices.Count;
}
}
}
else
{
// if there is no per-face material, place everything into one mesh
for (int c = 0; c < sourceMesh.PosFaces.Count; c++)
{
faces.Add(c);
numVertices += sourceMesh.PosFaces[c].Indices.Count;
}
}
// no faces/vertices using this material? strange...
if (numVertices == 0)
{
continue;
}
// create a submesh using this material
var mesh = new AssimpSharp.Mesh();
result.Add(mesh);
// find the material in the scene's material list. Either own material
// or referenced material, it should already have a valid index
if (sourceMesh.FaceMaterials.Count > 0)
{
mesh.MaterialIndex = sourceMesh.Materials[b].SceneIndex;
}
else
{
mesh.MaterialIndex = 0;
}
// Create properly sized data arrays in the mesh. We store unique vertices per face,
// as specified
mesh.NumVertices = numVertices;
mesh.Vertices = new Vector3[numVertices];
mesh.NumFaces = faces.Count;
mesh.Faces = new AssimpSharp.Face[mesh.NumFaces];
// normals?
if (sourceMesh.Normals.Count > 0)
{
mesh.Normals = new Vector3[numVertices];
}
// texture coords
for (int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS; c++)
{
if (sourceMesh.TexCoords[c] != null && sourceMesh.TexCoords[c].Count > 0)
{
mesh.TextureCoords[c] = new Vector3[numVertices];
}
}
// vertex colors
mesh.Colors = new Color4[AI_MAX_NUMBER_OF_COLOR_SETS][];
for (int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS; c++)
{
if (sourceMesh.Colors[c] != null && sourceMesh.Colors[c].Count > 0)
{
mesh.Colors[c] = new Color4[numVertices];
}
}
// now collect the vertex data of all data streams present in the imported mesh
int newIndex = 0;
var orgPoints = new int[numVertices];
for (int c = 0; c < faces.Count; c++)
{
int f = faces[c];
var pf = sourceMesh.PosFaces[f];
// create face. either triangle or triangle fan depending on the index count
var df = mesh.Faces[c] = new AssimpSharp.Face();
df.Indices = new int[pf.Indices.Count];
// collect vertex data for indices of this face
for (int d = 0; d < df.Indices.Length; d++)
{
df.Indices[d] = newIndex;
orgPoints[newIndex] = (int)pf.Indices[d];
// Position
mesh.Vertices[newIndex] = sourceMesh.Positions[(int)pf.Indices[d]];
// Normal, if present
if (mesh.HasNormals)
{
mesh.Normals[newIndex] = sourceMesh.Normals[(int)sourceMesh.NormalFaces[f].Indices[d]];
}
// texture coord sets
for (int e = 0; e < AI_MAX_NUMBER_OF_TEXTURECOORDS; e++)
{
if (mesh.HasTextureCoords(e))
{
var tex = sourceMesh.TexCoords[e][(int)pf.Indices[d]];
mesh.TextureCoords[e][newIndex] = new Vector3(tex.X, 1.0f - tex.Y, 0.0f);
}
}
// vertex color sets
for (int e = 0; e < AI_MAX_NUMBER_OF_COLOR_SETS; e++)
{
if (mesh.HasVertexColors(e))
{
mesh.Colors[e][newIndex] = sourceMesh.Colors[e][(int)pf.Indices[d]];
}
}
newIndex++;
}
}
Debug.Assert(newIndex == numVertices);
var bones = sourceMesh.Bones;
var newBones = new List<AssimpSharp.Bone>();
for (int c = 0; c < bones.Count; c++)
{
var obone = bones[c];
var oldWeights = new float[sourceMesh.Positions.Count];
for (int d = 0; d < obone.Weights.Count; d++)
{
oldWeights[(int)obone.Weights[d].Vertex] = obone.Weights[d].Weight;
}
var newWeights = new List<AssimpSharp.VertexWeight>(numVertices);
for (int d = 0; d < orgPoints.Length; d++)
{
float w = oldWeights[orgPoints[d]];
if (w > 0.0f)
{
newWeights.Add(new VertexWeight(d, w));
}
}
if (newWeights.Count == 0)
{
continue;
}
// create
var nbone = new AssimpSharp.Bone();
newBones.Add(nbone);
// copy name end matrix
nbone.Name = obone.Name;
nbone.OffsetMatrix = obone.OffsetMatrix;
nbone.NumWeights = newWeights.Count;
nbone.Weights = new VertexWeight[nbone.NumWeights];
for (int d = 0; d < newWeights.Count; d++)
{
nbone.Weights[d] = newWeights[d];
}
}
mesh.NumBones = newBones.Count;
if (newBones.Count > 0)
{
mesh.Bones = mesh.Bones.ToArray();
}
}
}
// allocate mesh index array in the node
node.Meshes.Capacity = meshes.Count;
// store all meshes in the mesh library of the scene and store their indices in the node
for (int a = 0; a < result.Count; a++)
{
scene.Meshes.Add(result[a]);
node.Meshes.Add(scene.Meshes.Count - 1);
}
}
private void ConvertCluster(List<aiBone> bones, Model model, Cluster cl, int[] outIndices, int[] indexOutIndices, int[] countOutIndices, Matrix nodeGlobalTransform)
{
var bone = new aiBone();
bones.Add(bone);
bone.Name = FixNodeName(cl.TargetNode.Name);
bone.OffsetMatrix = cl.TransformLink;
bone.OffsetMatrix.Invert();
bone.OffsetMatrix = bone.OffsetMatrix * nodeGlobalTransform;
bone.NumWeights = outIndices.Length;
var cursor = bone.Weights = new aiVertexWeight[outIndices.Length];
int cursor_index = 0;
int noIndexSentinel = int.MaxValue;
var weights = cl.Weights;
int c = indexOutIndices.Length;
for (int i = 0; i < c; i++)
{
int indexIndex = indexOutIndices[i];
if (indexIndex == noIndexSentinel)
{
continue;
}
int cc = countOutIndices[i];
for (int j = 0; j < cc; j++)
{
cursor[cursor_index].VertexId = outIndices[indexIndex + j];
cursor[cursor_index].Weight = weights[i];
j++;
}
}
}