// Instance API
static VrAssetService()
{
Matrix4x4 polyFromUnity = AxisConvention.GetFromUnity(AxisConvention.kGltfAccordingToPoly);
// Provably non-lossy: the mat4 is purely TRS, and the S is uniform
kPolyFromUnity = TrTransform.FromMatrix4x4(polyFromUnity);
}
/// Given a transform, returns that transform in another basis.
/// The new basis is specified by outputFromInput.
///
/// Not guaranteed to work if the change-of-basis matrix has non-uniform
/// scale. Otherwise, the resulting transform will not "fit" in a TrTransform.
public static TrTransform ChangeBasis(
TrTransform xfInput,
Matrix4x4 outputFromInput, Matrix4x4 inputFromOutput)
{
// It might make this a little more accurate if outputFromInput were a TrTransform.
// Although... outputFromInput and inputFromOutput expressed as Matrix4x4 are always
// infinitely precise, for axis convention changes at least. Doing the same with a quat
// might involve sqrt(2)s. But maybe not for the common case of unity -> fbx / gltf?
Matrix4x4 m = outputFromInput * xfInput.ToMatrix4x4() * inputFromOutput;
return(TrTransform.FromMatrix4x4(m));
}
public void TestFromMatrix4x4()
{
for (int i = 0; i < 100; ++i)
{
var t = Random.insideUnitSphere * 10;
var r = Random.rotationUniform;
var s = Random.Range(2f, 100f);
if (Random.value < .5f)
{
s = 1 / s;
}
var xf = TrTransform.TRS(t, r, s);
var m4 = Matrix4x4.TRS(t, r, Vector3.one * s);
AssertAlmostEqual(TrTransform.FromMatrix4x4(m4), xf, allowFlip: true);
}
}
private TrTransform UsdXformToWorldSpaceXform(USD.NET.Unity.XformSample usdXform)
{
TrTransform xf_CS = TrTransform.FromMatrix4x4(usdXform.transform);
return(TrTransform.FromTransform(App.Scene.ActiveCanvas.transform) * xf_CS);
}
static void SetLocalTransform(this FbxNode node, Matrix4x4 xf)
{
node.SetLocalTransform(TrTransform.FromMatrix4x4(xf));
}