How to use the @casual-simulation/aux-common.lerp function in @casual-simulation/aux-common

let theta = 0;
        if (this.setRotValues.y != 0.0091) {
            theta = this.setRotValues.y * Math.PI;
        } else {
            theta = this.spherical.theta;
        }

        // clamp theta and phi to exiting limits
        theta = Math.max(
            this.minAzimuthAngle,
            Math.min(this.maxAzimuthAngle, theta)
        );

        phi = Math.max(this.minPolarAngle, Math.min(this.maxPolarAngle, phi));

        this.spherical.phi = lerp(this.spherical.phi, phi, this.tweenNum);
        this.spherical.theta = lerp(this.spherical.theta, theta, this.tweenNum);

        if (this.tweenNum >= 1) {
            this.setRot = false;
        }
    }

if (this.setRotValues.y != 0.0091) {
            theta = this.setRotValues.y * Math.PI;
        } else {
            theta = this.spherical.theta;
        }

        // clamp theta and phi to exiting limits
        theta = Math.max(
            this.minAzimuthAngle,
            Math.min(this.maxAzimuthAngle, theta)
        );

        phi = Math.max(this.minPolarAngle, Math.min(this.maxPolarAngle, phi));

        this.spherical.phi = lerp(this.spherical.phi, phi, this.tweenNum);
        this.spherical.theta = lerp(this.spherical.theta, theta, this.tweenNum);

        if (this.tweenNum >= 1) {
            this.setRot = false;
        }
    }

this.spherical.theta = Math.max(
            this.minAzimuthAngle,
            Math.min(this.maxAzimuthAngle, this.spherical.theta)
        );

        // restrict phi to be between desired limits
        this.spherical.phi = Math.max(
            this.minPolarAngle,
            Math.min(this.maxPolarAngle, this.spherical.phi)
        );

        this.spherical.makeSafe();

        if (this._camera instanceof PerspectiveCamera) {
            if (this.zooming && this.spherical.radius != this.zoomSetValue) {
                this.sphereRadiusSetter = lerp(
                    this.spherical.radius,
                    this.zoomSetValue,
                    0.1
                );

                if (this.tweenNum >= 1) {
                    this.zooming = false;
                }

                this.spherical.radius = this.sphereRadiusSetter;
            } else {
                this.zooming = false;
                this.spherical.radius = this.sphereRadiusSetter;
            }
        }

private updateCamera() {
        if (this._camera instanceof OrthographicCamera) {
            if (this.zooming && this._camera.zoom != this.zoomSetValueOrtho) {
                this._camera.zoom = lerp(
                    this._camera.zoom,
                    this.zoomSetValueOrtho,
                    this.tweenNum
                );

                if (this.tweenNum >= 1) {
                    this.zooming = false;
                }

                this._camera.updateProjectionMatrix();
                this.zoomChanged = true;
            }
        }

        let offset = new Vector3();