UsageHints.MaskContainer

Description

Optimizes rendering of a VisualElement that has multiple descendants with nested masks.

This option reduces stencil state changes and capitalizes on consecutive mask push/pop operations for efficiency.

Apply this option to a VisualElement with multiple nested masks among its descendants. For example, a child element has the overflow: hidden; style with rounded corners or SVG background.

The following illustration shows the number of batches in a single-level masking, a nested masking, and a nested masking with MaskContainer. The yellow color indicates the masking elements. The orange color indicates the masking element with MaskContainer applied. The numbers indicate the number of batches.


A: Single-level masking (1 batch)
B: Nested masking (5 batches)
C: Nested masking with MaskContainer (2 batches)

Note: Don't use GroupTransform in scenarios with many subtrees, where each subtree uses two or more levels of masking. This helps minimize consecutive push/push or pop/pop operations.