CustomPainter layer?

[sqcsabbey]

I'm currently drawing a grid over the map using a CustomPainter in a Flutter Stack widget, but I'd like to put this on a map layer so I can place it below symbols; how can I do this?

[samderlust]

I can think of 2 solutions for this.

1. make another layer of widgets of symbols
2. instead of CusomterPainer widget, make it in to []byte and add as image source layer of mapbox

[Betlis007]

Re 1: "Symbols" have the problem that they are only defined by one coordinate and the grid is not displayed correctly with a zoom with intermediate levels (e.g. zoom 13.5).
Re 2: In the current solution, a layer can only hold one image source (see controller.addImageLayer: LAYER_ID, SOURCE_ID, ...). For example, if you want to render individual tiles locally, you would have one layer per tile, which is very unattractive.
Is there no other solution to add raster objects rendered on the device to a layer and overlay them on the map? Thanks for any tips.