Custom 3D geometry layer does not render on MapLibre map (type: "custom", renderingMode: "3d")

[HSUCHING]

maplibre-gl-js version:

5.1.0

@maptiler/sdk version:

3.0.1

Browser:

Google Chrome

Steps to Trigger Behavior
1. Initialize a maplibregl.Map instance with renderingMode: "3d".
2. Add a custom WebGL layer (type: "custom") to render a non-regular 3D object.
3. The map loads, but the custom 3D object does not appear on the map.

`
const map = new maplibregl.Map({
container: "map",
style: "https://api.maptiler.com/maps/streets/style.json?key=YOUR_MAPTILER_KEY",
center: [121.5, 31.2], // Example coordinates
zoom: 15,
pitch: 60,
bearing: 30,
renderingMode: "3d",
});

map.on("load", () => {
map.addLayer({
id: "custom-3d-layer",
type: "custom",
renderingMode: "3d",
onAdd: function (map, gl) {
this.gl = gl;
this.program = gl.createProgram(); // Custom WebGL setup here
// Shader setup, buffer initialization, etc.
},
render: function (gl, matrix) {
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
// WebGL rendering logic for 3D object
},
});
});

.....................
`

Expected Behavior

The custom 3D geometry should render correctly on the map, appearing above the terrain.

Actual Behavior

The custom 3D object does not appear on the map. The map itself loads normally. No errors appear in the console.

This prevents me from rendering custom 3D objects on MapLibre maps using type: "custom" layers. Please advise on possible solutions or workarounds.

[HarelM]

There are examples of how to write those, did you try modifying those?