Custom layers: how do I refresh only the custom layer?

mapbox-gl-js version:0.53.1

Question

When using a custom layer with a webgl shader, I implemented the render method of the layer object:

class CustomLayer {
  render(gl, matrix) {
     /** drawing to the context **/

    // this rerenders all the layers
     this.map.triggerRepaint();
  }
}

I can see using the Chrome performance tool that all the layers are redrawing.
https://docs.mapbox.com/mapbox-gl-js/example/add-3d-model/

For an animated custom layer on top of a static map, redrawing all layers at each frame seems aggressive. How could I refresh only the custom layer?

My use case: I coded a shader that runs at 60fps 4% CPU outside of Mapbox with low GPU activity, but I end up having to slow it down to only 15fps, 40% CPU when used as a layer in Mapbox due to the map under being fairly complex.

Links to related documentation

I mostly use this section of the documentation: https://docs.mapbox.com/mapbox-gl-js/example/custom-style-layer/

Thank you!

Start with the custom-style-layer and add-3d-model examples, then trace the CustomLayer.render call and this.map.triggerRepaint() behavior described in the issue. Done means establishing whether selective custom-layer refresh is supported and documenting the appropriate behavior or required API change.