Different calculate result when convert pivot animation between sdk2018 and sdk2020

[xingyufengVVWJC]

Problem Describe：

Consider this joint orientation in the picture，

it's lcl rotation is (-143.73, 24.61, 13.34) and rotation order is zyx, at the same time, we have some prerotation which it's value is (-131.91, 12.11, -115.21), so in order to get rid of this prerotation, i set the destination pivotset's prerotation is zero and keep the rotation order as the source. It's code like below:

Python:

def set_node_state_recursively(node)

    zero_vec = FbxVector4(0, 0, 0, 0)

    source_rotation_order = node.GetRotationOrder(FbxNode.EPivotSet.eSourcePivot)

    node.SetPivotState(FbxNode.EPivotSet.eSourcePivot, FbxNode.EPivotState.ePivotActive)

    node.SetPivotState(FbxNode.EPivotSet.eDestinationPivot, FbxNode.EPivotState.ePivotActive)

    node.SetPreRotation(FbxNode.EPivotSet.eDestinationPivot, zero_vec)

    node.SetPostRotation(FbxNode.EPivotSet.eDestinationPivot, zero_vec)

    node.SetRotationOrder(FbxNode.EPivotSet.eDestinationPivot, source_rotation_order)

    for i in range(node.GetChildCount()):

        set_node_state_recursively(node.GetChild(i))

def convert_animation(root_node)

    set_node_state_recursively(root_node)

    root_node.ConvertPivotAnimationRecursive(None, FbxNode.EPivotSet.eDestinationPivot, 60, False)

But in sdk 2018.1.1 it will get result with final rotation (-32.49, -90.00, -32.49) which is wrong, but in the sdk 2020.3, it's result will be (45, -90, -45). From visual perspective, the 2020.3 sdk get the right result.

So, I am quite curious about what happened behind the sdk and why it calculate different result，thank you in advance and hope get some help from fbx guys.