@openhps/core/src/nodes/processing/ReferenceSpaceConversionNode.ts

Open Hybrid Positioning System - Core component

import { ObjectProcessingNode, ObjectProcessingNodeOptions } from '../ObjectProcessingNode';
import { Model } from '../../Model';
import { ReferenceSpace, DataFrame, DataObject, SpaceTransformationOptions } from '../../data';

/**
 * This node converts the positions of data objects inside the frame
 * to another reference space.
 * @category Processing node
 */
export class ReferenceSpaceConversionNode<InOut extends DataFrame> extends ObjectProcessingNode<InOut> {
    private _referenceSpaceUID: string;
    private _referenceSpace: ReferenceSpace;
    protected options: SpaceConversionOptions;

    constructor(referenceSpace: ReferenceSpace | string, options?: SpaceConversionOptions) {
        super(options);
        if (referenceSpace instanceof ReferenceSpace) {
            this._referenceSpace = referenceSpace;
            this._referenceSpaceUID = referenceSpace.uid;
        } else {
            this._referenceSpaceUID = referenceSpace;
        }

        this.once('build', this._onRegisterService.bind(this));
    }

    private _onRegisterService(): Promise<void> {
        return new Promise<void>((resolve) => {
            const service = (this.graph as Model).findDataService<ReferenceSpace>(ReferenceSpace);
            // Update reference space when modified
            service.on('insert', (uid: string, space: ReferenceSpace) => {
                if (uid === this._referenceSpaceUID) {
                    this._referenceSpace = space;
                }
            });

            // Update to the latest version
            service
                .findByUID(this._referenceSpaceUID)
                .then((space: ReferenceSpace) => {
                    this._referenceSpace = space;
                    resolve();
                })
                .catch(() => {
                    // Ignore, most likely not calibrated or stored yet
                    resolve();
                });
        });
    }

    public processObject(object: DataObject, frame: InOut): Promise<DataObject> {
        return new Promise<DataObject>((resolve) => {
            // First check if a reference space is provided inside
            // the data frame. If not, use the stored reference space
            let referenceSpace = frame.getObjectByUID(this._referenceSpaceUID) as ReferenceSpace;
            if (referenceSpace === null || referenceSpace === undefined) {
                referenceSpace = this._referenceSpace;
            }

            if (object.getPosition() && object.uid !== referenceSpace.uid) {
                if (this.options.inverse) {
                    // Convert from reference space to global
                    object.setPosition(object.getPosition(), referenceSpace);
                } else {
                    // Convert global space to reference space
                    object.setPosition(object.getPosition(referenceSpace));
                }
            }
            resolve(object);
        });
    }
}

export interface SpaceConversionOptions extends ObjectProcessingNodeOptions, SpaceTransformationOptions {}