WPF DrawingVisual Patterns

DrawingVisual is a lightweight visual element faster than Shape, suitable for large-scale rendering.

1. Visual Hierarchy

Visual (abstract)
├── UIElement
│   └── FrameworkElement
│       └── Shape (heavyweight, event support)
│
├── DrawingVisual       ← Lightweight, no events, direct rendering
├── ContainerVisual     ← Groups multiple Visuals
└── HostVisual          ← Cross-thread Visual