kotlin-cesium-engine/cesium.engine/IonSnapService

IonSnapService

open external class IonSnapService(options: IonSnapService.ConstructorOptions)(source)

Provides interactive snap-to-geometry against a Cesium ion 3D Tiles asset backed by a BIM/CAD Database model, using the ion REST API's element snap endpoint.

This class handles conversions between the reference frame of a source BIM/CAD Database and the view-dependent screen space pixel coordinates. Each snap, it transforms using the ion asset's source reference frame, the camera's transform, and the canvas dimensions so that view-dependent features— such as the pixel aperture, nearest position, or surface tracking— behave correctly.

This object is normally not instantiated directly, use IonSnapService.fromAssetId.

const snapper = await IonSnapService.fromAssetId(123456);
const canvas = viewer.scene.canvas;
const result = await snapper.snap({
  elementId: "0x30000000df2",
  testPoint: pickedPosition,
  camera: viewer.camera,
  canvasWidth: canvas.clientWidth,
  canvasHeight: canvas.clientHeight,
});
if (defined(result)) {
  console.log("snapped to", result.snapPoint);
}