What's happening here?

This example demonstrates UINineSlice elements for creating scalable UI components with preserved border regions. A vignette overlay is created using nine-slice scaling.

// Create nine-slice element with 15% border
const vignette = new UINineSlice(
  layer,
  baseScene.loadedTextures["T_Vignette"],
  { sliceBorders: 0.2, sliceRegions: 100 },
);

// Configure appearance
vignette.color.setHexRGB(0xffa500, 0.75);

// Use cover constraints to fill the entire layer
UICoverConstraintBuilder.build(layer, vignette, {
  keepActiveAspect: false,
});