I am trying to implement a custom autorotation, but I am failing to make it smooth as my fps can change dynamically and the rotation is lagging when it changes.

The current implementation looks following:

```
startAutorotation() {
autorotationInterval = setInterval(() => this.autoRotate(1), 10); // Rotate every 10 ms
}
stopAutorotation() {
if (autorotationInterval) {
clearInterval(autorotationInterval);
}
}
// This part taken from ArcballControlls
rotate(axis: Vector3, angle: number) {
const point = this._gizmos.position; //rotation center
this._translationMatrix.makeTranslation(-point.x, -point.y, -point.z);
this._rotationMatrix.makeRotationAxis(axis, -angle);
//rotate camera
this._m4_1.makeTranslation(point.x, point.y, point.z);
this._m4_1.multiply(this._rotationMatrix);
this._m4_1.multiply(this._translationMatrix);
this.setTransformationMatrices(this._m4_1);
return _transformation;
}
applyTransformMatrix(transformation: TransformationType) {
if (transformation.camera != null && this.camera) {
this._m4_1
.copy(this._cameraMatrixState)
.premultiply(transformation.camera);
this._m4_1.decompose(
this.camera.position,
this.camera.quaternion,
this.camera.scale
);
this.camera.updateMatrix();
//update camera up vector
this.camera.up
.copy(this._upState)
.applyQuaternion(this.camera.quaternion);
}
...
}
autoRotate = (speed = 1) => {
this.applyTransformMatrix(
this.rotate(new Vector3(0, speed, 0), Math.PI / 3000) // Rotate around Y axis.
);
this.camera.lookAt(this.target);
};
```

Is there a way to make it smooth? I believe I need to use Clock.getDelta() to calculate rotation angle, but I am not sure how.

Also, there is a bonus question. I want it to always rotate around vertical axis, but when I update `camera.up`

camera sees “vertical” differently. How can I calculate the vector to rotate camera around, so the rotation is aways around viewer perceived `Y`

axis?

I believe these questions are quite basic, but for some reason, I’m stuck on them.