C# 镜像网格和错误的UV贴图运行时导出
编辑:所以在与Assimp开发人员进行了简短的接触之后,我被指向了导入过程。当我从其他人手中接过代码时,我并不认为这一部分:C# 镜像网格和错误的UV贴图运行时导出,c#,unity3d,assimp,C#,Unity3d,Assimp,编辑:所以在与Assimp开发人员进行了简短的接触之后,我被指向了导入过程。当我从其他人手中接过代码时,我并不认为这一部分: using (var importer = new AssimpContext()) { scene = importer.ImportFile(file, PostProcessSteps.Triangulate | PostProcessSteps.FlipUVs | PostProcessSteps.JoinIdenticalVertices); } Fli
using (var importer = new AssimpContext())
{
scene = importer.ImportFile(file, PostProcessSteps.Triangulate | PostProcessSteps.FlipUVs | PostProcessSteps.JoinIdenticalVertices);
}
FlipUV完全按照它所说的做,它在y轴上翻转,因此原点现在位于左上角。因此,现在我可以得到适当的UV模型,但仍然是镜像网格。将父对象的比例设置为x=-1会将其翻转回正常状态并使其看起来很好,但我猜这并不是故意的。所以我一直在找
如图所示,有两种起重机型号。左侧的一个在运行时通过序列化和重建加载,而右侧的一个是原始的一个,只是简单地拖动到场景中。 序列化使用Assimp库进行 地板恰好是首先创建的,似乎得到了正确的uv贴图。而其他项目得到错误的uv贴图。虽然我正在打印uv贴图的值,但它们似乎与原始贴图匹配 这是如何序列化的,这是Assimp的Mesh类,而不是Unity Mesh类,应用序列化是UWP中内置的Windows应用程序:
private static void SerializeMeshes(BinaryWriter writer, IEnumerable<Mesh> meshes)
{
foreach (Mesh mesh in meshes)
{
ICollection<int> triangles = MeshLoadTriangles(mesh);
MeshSerializeHeader(writer, mesh.Name, mesh.VertexCount, triangles.Count, mesh.MaterialIndex);
MeshSerializeVertices(writer, mesh.Vertices);
MeshSerializeUVCoordinate(writer, mesh.TextureCoordinateChannels);
MeshSerializeTriangleIndices(writer, triangles);
}
}
private static void MeshSerializeUVCoordinate(BinaryWriter writer, List<Vector3D>[] textureCoordinateChannels)
{
// get first channel and serialize to writer. Discard z channel
// This is Vector3D since happening outside Unity
List<Vector3D> list = textureCoordinateChannels[0];
foreach (Vector3D v in list)
{
float x = v.X;
float y = v.Y;
writer.Write(x);
writer.Write(y);
}
}
private static void MeshSerializeVertices(BinaryWriter writer, IEnumerable<Vector3D> vertices)
{
foreach (Vector3D vertex in vertices)
{
Vector3D temp = vertex;
writer.Write(temp.X);
writer.Write(temp.Y);
writer.Write(temp.Z);
}
}
private static void MeshSerializeTriangleIndices(BinaryWriter writer, IEnumerable<int> triangleIndices)
{
foreach (int index in triangleIndices) { writer.Write(index); }
}
我在代码中没有看到任何导致这种行为的原因,我想说,如果值错误,它将完全破坏网格
我可以看到,我的fbx文件使用的是四边形而不是三角形作为索引
可能是因为Assimp与此不匹配吗?我没有从Assimp以正确的方式解决问题 我们使用的基本解决方案是负比例缩放对象变换中翻转的轴 一个更合适的解决方案是将所有顶点馈送到Unity侧的一个矩阵,以便它正确解析顶点的位置
- 获取顶点列表
- foreach顶点与旋转矩阵相乘
- 将数组指定给网格
- 使用网格渲染
private static void DeserializeMeshes(BinaryReader reader, SceneGraph scene)
{
MeshData[] meshes = new MeshData[scene.meshCount];
for (int i = 0; i < scene.meshCount; i++)
{
meshes[i] = new MeshData();
MeshReadHeader(reader, meshes[i]);
MeshReadVertices(reader, meshes[i]);
MeshReadUVCoordinate(reader, meshes[i]);
MeshReadTriangleIndices(reader, meshes[i]);
}
scene.meshes = meshes as IEnumerable<MeshData>;
}
private static void MeshReadUVCoordinate(BinaryReader reader, MeshData meshData)
{
bool hasUv = reader.ReadBoolean();
if(hasUv == false) { return; }
Vector2[] uvs = new Vector2[meshData.vertexCount];
for (int i = 0; i < uvs.Length; i++)
{
uvs[i] = new Vector2();
uvs[i].x = reader.ReadSingle();
uvs[i].y = reader.ReadSingle();
}
meshData.uvs = uvs;
}
private static void MeshReadHeader(BinaryReader reader, MeshData meshData)
{
meshData.name = reader.ReadString();
meshData.vertexCount = reader.ReadInt32();
meshData.triangleCount = reader.ReadInt32();
meshData.materialIndex = reader.ReadInt32();
}
private static void MeshReadVertices(BinaryReader reader, MeshData meshData)
{
Vector3[] vertices = new Vector3[meshData.vertexCount];
for (int i = 0; i < vertices.Length; i++)
{
vertices[i] = new Vector3();
vertices[i].x = reader.ReadSingle();
vertices[i].y = reader.ReadSingle();
vertices[i].z = reader.ReadSingle();
}
meshData.vertices = vertices;
}
private static void MeshReadTriangleIndices(BinaryReader reader, MeshData meshData)
{
int[] triangleIndices = new int[meshData.triangleCount];
for (int i = 0; i < triangleIndices.Length; i++)
{
triangleIndices[i] = reader.ReadInt32();
}
meshData.triangles = triangleIndices;
}
private static Mesh[] CreateMeshes(SceneGraph scene)
{
Mesh[] meshes = new Mesh[scene.meshCount];
int index = 0;
foreach (MeshData meshData in scene.meshes)
{
meshes[index] = new Mesh();
Vector3[] vec = meshData.vertices;
meshes[index].vertices = vec;
meshes[index].triangles = meshData.triangles;
meshes[index].uv = meshData.uvs;
meshes[index].normals = meshData.normals;
meshes[index].RecalculateNormals();
index++;
}
return meshes;
}