public static void ExportSkeleton(ObjectContext objContext, ExportContext exportContext)
{
var scene = exportContext.scene;
var sample = (SkeletonSample)objContext.sample;
var boneNames = exportContext.skelSortedMap[objContext.gameObject.transform];
sample.joints = new string[boneNames.Count];
sample.bindTransforms = new Matrix4x4[boneNames.Count];
sample.restTransforms = new Matrix4x4[boneNames.Count];
string rootPath = UnityTypeConverter.GetPath(objContext.gameObject.transform);
sample.transform = XformExporter.GetLocalTransformMatrix(
objContext.gameObject.transform,
scene.UpAxis == Scene.UpAxes.Z,
new pxr.SdfPath(rootPath).IsRootPrimPath(),
exportContext.basisTransform);
int i = 0;
foreach (string bonePath in boneNames)
{
if (string.IsNullOrEmpty(bonePath))
{
sample.joints[i] = "";
i++;
continue;
}
var bone = exportContext.pathToBone[bonePath];
if (bonePath == rootPath)
{
sample.joints[i] = "/";
}
else
{
sample.joints[i] = bonePath.Replace(rootPath + "/", "");
}
// TODO: When the bone bind transform contains the geomBindTransform from USD import, it
// will be mixed into each bone. This transform should be saved in some way and removed
// when exported as a skeleton.
sample.bindTransforms[i] = exportContext.bindPoses[bone].inverse;
sample.restTransforms[i] = XformExporter.GetLocalTransformMatrix(
bone, false, false, exportContext.basisTransform);
if (exportContext.basisTransform == BasisTransformation.SlowAndSafe)
{
sample.bindTransforms[i] = UnityTypeConverter.ChangeBasis(sample.bindTransforms[i]);
// The restTransforms will get a change of basis from GetLocalTransformMatrix().
}
i++;
}
scene.Write(objContext.path, sample);
// Stop Skeleton from rendering bones in usdview by default.
var im = new pxr.UsdGeomImageable(scene.GetPrimAtPath(objContext.path));
im.CreatePurposeAttr().Set(pxr.UsdGeomTokens.guide);
}
public static void ExportSkelRoot(ObjectContext objContext, ExportContext exportContext)
{
var sample = (SkelRootSample)objContext.sample;
// Compute bounds for the root, required by USD.
bool first = true;
// Ensure the bounds are computed in root-local space.
// This is required because USD expects the extent to be a local bound for the SkelRoot.
var oldParent = objContext.gameObject.transform.parent;
objContext.gameObject.transform.SetParent(null, worldPositionStays: false);
try
{
foreach (var r in objContext.gameObject.GetComponentsInChildren <Renderer>())
{
if (first)
{
// Ensure the bounds object starts growing from the first valid child bounds.
first = false;
sample.extent = r.bounds;
}
else
{
sample.extent.Encapsulate(r.bounds);
}
}
}
finally
{
// Restore the root parent.
objContext.gameObject.transform.SetParent(oldParent, worldPositionStays: false);
}
// Convert handedness if needed.
if (exportContext.basisTransform == BasisTransformation.SlowAndSafe)
{
sample.extent.center = UnityTypeConverter.ChangeBasis(sample.extent.center);
}
// Convert the transform
var path = new pxr.SdfPath(objContext.path);
// If exporting for Z-Up, rotate the world.
bool correctZUp = exportContext.scene.UpAxis == Scene.UpAxes.Z;
sample.transform = XformExporter.GetLocalTransformMatrix(
objContext.gameObject.transform,
correctZUp,
path.IsRootPrimPath(),
exportContext.basisTransform);
exportContext.scene.Write(objContext.path, sample);
}
static void ExportMesh(ObjectContext objContext,
ExportContext exportContext,
Mesh mesh,
Material sharedMaterial,
Material[] sharedMaterials,
bool exportMeshPose = true)
{
string path = objContext.path;
if (mesh == null)
{
Debug.LogWarning("Null mesh for: " + path, objContext.gameObject);
return;
}
#if UNITY_EDITOR
if (!CanReadMesh(mesh))
{
#else
if (!mesh.isReadable)
{
#endif
Debug.LogError(
"Mesh is not readable: " + objContext.path +
". To fix this, enable read/write in the inspector for the source asset that you are attempting to export.",
objContext.gameObject);
return;
}
var scene = exportContext.scene;
bool unvarying = scene.Time == null;
bool slowAndSafeConversion = exportContext.basisTransform == BasisTransformation.SlowAndSafe;
var sample = (MeshSample)objContext.sample;
var go = objContext.gameObject;
if (mesh.bounds.center == Vector3.zero && mesh.bounds.extents == Vector3.zero)
{
mesh.RecalculateBounds();
}
sample.extent = mesh.bounds;
if (slowAndSafeConversion)
{
// Unity uses a forward vector that matches DirectX, but USD matches OpenGL, so a change of
// basis is required. There are shortcuts, but this is fully general.
sample.ConvertTransform();
sample.extent.center = UnityTypeConverter.ChangeBasis(sample.extent.center);
}
// Only export the mesh topology on the first frame.
if (unvarying)
{
// TODO: Technically a mesh could be the root transform, which is not handled correctly here.
// It should have the same logic for root prims as in ExportXform.
sample.transform = XformExporter.GetLocalTransformMatrix(
go.transform,
scene.UpAxis == Scene.UpAxes.Z,
new pxr.SdfPath(path).IsRootPrimPath(),
exportContext.basisTransform);
sample.normals = mesh.normals;
sample.points = mesh.vertices;
sample.tangents = mesh.tangents;
sample.colors = mesh.colors;
if (sample.colors != null && sample.colors.Length == 0)
{
sample.colors = null;
}
if ((sample.colors == null || sample.colors.Length == 0) &&
(sharedMaterial != null && sharedMaterial.HasProperty("_Color")))
{
sample.colors = new Color[1];
sample.colors[0] = sharedMaterial.color.linear;
}
// Gah. There is no way to inspect a meshes UVs.
sample.st = mesh.uv;
// Set face vertex counts and indices.
var tris = mesh.triangles;
if (slowAndSafeConversion)
{
// Unity uses a forward vector that matches DirectX, but USD matches OpenGL, so a change
// of basis is required. There are shortcuts, but this is fully general.
for (int i = 0; i < sample.points.Length; i++)
{
sample.points[i] = UnityTypeConverter.ChangeBasis(sample.points[i]);
if (sample.normals != null && sample.normals.Length == sample.points.Length)
{
sample.normals[i] = UnityTypeConverter.ChangeBasis(sample.normals[i]);
}
if (sample.tangents != null && sample.tangents.Length == sample.points.Length)
{
var w = sample.tangents[i].w;
var t = UnityTypeConverter.ChangeBasis(sample.tangents[i]);
sample.tangents[i] = new Vector4(t.x, t.y, t.z, w);
}
}
for (int i = 0; i < tris.Length; i += 3)
{
var t = tris[i];
tris[i] = tris[i + 1];
tris[i + 1] = t;
}
}
sample.SetTriangles(tris);
UnityEngine.Profiling.Profiler.BeginSample("USD: Mesh Write");
scene.Write(path, sample);
UnityEngine.Profiling.Profiler.EndSample();
// TODO: this is a bit of a half-measure, we need real support for primvar interpolation.
// Set interpolation based on color count.
if (sample.colors != null && sample.colors.Length == 1)
{
pxr.UsdPrim usdPrim = scene.GetPrimAtPath(path);
var colorPrimvar =
new pxr.UsdGeomPrimvar(usdPrim.GetAttribute(pxr.UsdGeomTokens.primvarsDisplayColor));
colorPrimvar.SetInterpolation(pxr.UsdGeomTokens.constant);
var opacityPrimvar =
new pxr.UsdGeomPrimvar(usdPrim.GetAttribute(pxr.UsdGeomTokens.primvarsDisplayOpacity));
opacityPrimvar.SetInterpolation(pxr.UsdGeomTokens.constant);
}
string usdMaterialPath;
if (exportContext.exportMaterials && sharedMaterial != null)
{
if (!exportContext.matMap.TryGetValue(sharedMaterial, out usdMaterialPath))
{
Debug.LogError("Invalid material bound for: " + path);
}
else
{
MaterialSample.Bind(scene, path, usdMaterialPath);
}
}
// In USD subMeshes are represented as UsdGeomSubsets.
// When there are multiple subMeshes, convert them into UsdGeomSubsets.
if (mesh.subMeshCount > 1)
{
// Build a table of face indices, used to convert the subMesh triangles to face indices.
var faceTable = new Dictionary <Vector3, int>();
for (int i = 0; i < tris.Length; i += 3)
{
if (!slowAndSafeConversion)
{
faceTable.Add(new Vector3(tris[i], tris[i + 1], tris[i + 2]), i / 3);
}
else
{
// Under slow and safe export, index 0 and 1 are swapped.
// This swap will not be present in the subMesh indices, so must be undone here.
faceTable.Add(new Vector3(tris[i + 1], tris[i], tris[i + 2]), i / 3);
}
}
var usdPrim = scene.GetPrimAtPath(path);
var usdGeomMesh = new pxr.UsdGeomMesh(usdPrim);
// Process each subMesh and create a UsdGeomSubset of faces this subMesh targets.
for (int si = 0; si < mesh.subMeshCount; si++)
{
int[] indices = mesh.GetTriangles(si);
int[] faceIndices = new int[indices.Length / 3];
for (int i = 0; i < indices.Length; i += 3)
{
faceIndices[i / 3] = faceTable[new Vector3(indices[i], indices[i + 1], indices[i + 2])];
}
var vtIndices = UnityTypeConverter.ToVtArray(faceIndices);
var subset = pxr.UsdGeomSubset.CreateUniqueGeomSubset(
usdGeomMesh, // The object of which this subset belongs.
m_subMeshesToken, // An arbitrary name for the subset.
pxr.UsdGeomTokens.face, // Indicator that these represent face indices
vtIndices, // The actual face indices.
m_materialBindToken // familyName = "materialBind"
);
if (exportContext.exportMaterials)
{
if (si >= sharedMaterials.Length || !sharedMaterials[si] ||
!exportContext.matMap.TryGetValue(sharedMaterials[si], out usdMaterialPath))
{
Debug.LogWarning("Invalid material bound for: " + path + "\n"
+ (si >= sharedMaterials.Length
? "More submeshes than materials assigned."
: (!sharedMaterials[si]
? "Submesh " + si + " has null material"
: "ExportMap can't map material")));
}
else
{
MaterialSample.Bind(scene, subset.GetPath(), usdMaterialPath);
}
}
}
}
}
else
{
// Only write the transform when animating.
var meshSample = new MeshSampleBase();
meshSample.extent = sample.extent;
meshSample.transform = XformExporter.GetLocalTransformMatrix(
go.transform,
scene.UpAxis == Scene.UpAxes.Z,
new pxr.SdfPath(path).IsRootPrimPath(),
exportContext.basisTransform);
if (exportMeshPose)
{
meshSample.points = mesh.vertices;
// Set face vertex counts and indices.
var tris = mesh.triangles;
if (slowAndSafeConversion)
{
// Unity uses a forward vector that matches DirectX, but USD matches OpenGL, so a change
// of basis is required. There are shortcuts, but this is fully general.
for (int i = 0; i < meshSample.points.Length; i++)
{
meshSample.points[i] = UnityTypeConverter.ChangeBasis(meshSample.points[i]);
}
for (int i = 0; i < tris.Length; i += 3)
{
var t = tris[i];
tris[i] = tris[i + 1];
tris[i + 1] = t;
}
}
sample.SetTriangles(tris);
}
UnityEngine.Profiling.Profiler.BeginSample("USD: Mesh Write");
scene.Write(path, meshSample);
UnityEngine.Profiling.Profiler.EndSample();
}
}
}
