DynamicSpatialClassifier Interface

A SpatialClassifier that uses geoemtry produced at run-time to classify a reality model. The geometry is supplied by a TileTreeReference. A simple example of creating and applying a dynamic classifier:

/** A spatial region described by a bounding sphere, used to classify a reality model. */
interface ClassifiedRegion {
  /** The center point of the bounding sphere. */
  center: Point3d;
  /** The radius of the bounding sphere. */
  radius: number;
  /** The name of the region, to serve as a tooltip when the user hovers over the classified region of the reality model. */
  name: string;
  /** The color in which to draw the classified region of the reality model. */
  color: ColorDef;

/** Classify spherical regions of a reality model, either by planar projection (`classifyByVolume=false`) or by bounding volume (`classifyByVolume=true`). */
export function classifyRealityModel(model: ContextRealityModelState, regions: ClassifiedRegion[], classifyByVolume: boolean): void {
  const modelId = model.iModel.transientIds.getNext();

  // Create a GraphicBuilder to define the classifier geometry.
  const builder = IModelApp.renderSystem.createGraphic({
    type: GraphicType.Scene,
    computeChordTolerance: () => 0.01,
    pickable: {
      id: modelId,
      isVolumeClassifier: classifyByVolume,

  const regionIdsAndNames: Array<{ name: string, id: Id64String }> = [];

  for (const region of regions) {
    // Assign a unique Id to each region, so we can identify them when the user interacts with them in a viewport.
    const regionId = model.iModel.transientIds.getNext();
    regionIdsAndNames.push({ id: regionId, name: region.name });

    // Add a sphere representing the region.
    builder.setSymbology(region.color, region.color, 1);
    builder.addSolidPrimitive(Sphere.createCenterRadius(region.center, region.radius));

  // Create a tile tree reference to provide the graphics at display time.
  const tileTreeReference = TileTreeReference.createFromRenderGraphic({
    graphic: builder.finish(),
    iModel: model.iModel,
    getToolTip: async (hit) => Promise.resolve(regionIdsAndNames.find((x) => x.id === hit.sourceId)?.name),

  // Direct the reality model to use our tile tree reference for classification.
  model.classifiers.activeClassifier = {
    name: "Regions",
    flags: new SpatialClassifierFlags(undefined, undefined, classifyByVolume),

@see SpatialClassifiersState to configure a reality model's classifiers.


Name Type Description
flags SpatialClassifierFlags Flags controlling how to apply the classifier.  
name string A user-friendly name appropriate for use in a user interface.  
tileTreeReference TileTreeReference A reference to the TileTree that supplies the graphics used to classify the reality model.  

Defined in

Last Updated: 05 April, 2024