Version: 2019.4

説明

Marks a VisualElement that hosts many children with DynamicTransform applied on them. A common use-case of this hint is a VisualElement that represents a "viewport" within which there are many DynamicTransform VisualElements that can move individually in addition to the "viewport" element also often changing its transformation. However, if the contents of the aforementioned "viewport" element are mostly static (not moving) then it is enough to use the DynamicTransform hint on that element instead of GroupTransform. Internally, an element hinted with GroupTransform will force a separate draw batch with its world transformation value, but in the same time it will avoid changing the transforms of all its descendants whenever a transformation change occurs on the GroupTransform element.