PeachBrackets
PeachBrackets.Annotations.PageFormField
PageFormField.AppearanceTransform Property
The linear part of the transform that carries the upright appearance to where the control was drawn (translation left out, since the consumer fits the transformed appearance to Bounds), in the same y-down convention as Bounds; null when the control was not transformed or the transform is not affine (it is then drawn as its upright bounding box).
public System.Nullable<System.Numerics.Matrix3x2> AppearanceTransform { get; init; }