3rd party batch model (b3dm) in Mapbox v3?

[bertt]

Hi, is there some information/minimal sample (without compression) of visualizing a b3dm in Mapbox v3?

I'm retrieving the b3dm using:

map.addSource('tiles', {
        "type": "batched-model",
        "maxzoom": 14,
        "minzoom": 14,
        "tiles": [
          "https://myserver/{z}-{x}-{y}.b3dm"
        ]
      }
)});

questions:

• What is the axis ordening in the glTF's? (z up? in meters?)

• What x, y coordinates to use in the glTF? epsg:3857? absolute or relative to the tile? Relative to what?

• How does it work when enabling terrain? Are batched models hidden by the terrain (like Cesium setting depthTestAgainstTerrain)?

Any other requirements in the glTF? Draco compression? MAPBOX_mesh_features extension? mapbox:footprint:id/mapbox:coordinate-space/mapbox:footprint-quantized/mapbox:footprint-version/mapbox:tile-version?

[astojilj]

Thanks @bertt

For the context, pasting earlier comment https://twitter.com/astojilj/status/1693498420579766656?s=20

Mapbox tiles use Z-up orientation with Z in meters and X and Y in tile coordinates https://github.com/mapbox/mapbox-gl-js-internal/blob/94c7b65cdc8a861eeddd12e4f726407984e8c879/3d-style/render/draw_model.js#L741. Please, use https://github.com/mapbox/mapbox-gl-js to request and then track progress on supporting 3rd party tiles that follow 3D Tiles 1.0 and 3D Tiles Next.

Note that this is experimental functionality, and we don't plan to support experiments with custom b3dm tiles while we are focusing on developing Standard Style. Our future plans include 3D Tiles Next support, but I cannot share any details now.

What x, y coordinates to use in the glTF? epsg:3857? absolute or relative to the tile? Relative to what?

It follows Web Mercator projection (epsg:3857) - Mapbox Vector Tile Format https://docs.mapbox.com/style-spec/reference/sources/#vector.

All geometric coordinates in vector tiles must be between -1 * extent and (extent * 2) - 1 inclusive

EXTENT:

mapbox-gl-js/src/style-spec/data/extent.js

Line 18 in 068a7f3

export default 8192;

[bertt]

Got a step further, see https://bertt.github.io/mapbox_3dtiles_samples/samples/standard/dam_square/ (MapBox version v3.1.2)

Loading tileset:

map.addSource('bag-3d', {
        "type": "batched-model",
        "maxzoom": 15,
        "minzoom": 15,
        "tiles": [
          "https://bertt.github.io/mapbox_3dtiles_samples/samples/standard/dam_square/tiles/{z}-{x}-{y}.glb"
        ]
      }
)});

// add the custom style layer to the map
map.on('style.load', () => {
  map.addLayer({
    id: 'bag-layer',
    type: 'model',
    source: 'bag-3d',          
  });
});

There is one glb (15-16829-10768.glb), center should be at Amsterdam Dam Square (

). In this demo I used in the vertex coordinates between 3500 and 3600 after trial and error, to get the model on the Dam square. When using 0,0 the model is drawn on the top left of the tile.

So I image the model vertex coordinates are relative to the upper left of the tile.

[astojilj]

@bertt
Yes, the tile coordinate X increases from left to right in range [0 .. 8192), and Y increases [0 .. 8192) from north to south. Now, we use single zoom 14 .glb tiles only.

I would like to understand your use case better as we are working on a number of things:

#13009 (comment)

Note the approaches for hiding all 3D content from Standard Style and the "conflation" part related to bringing own 3D models to the map, which would hide overlapping Mapbox 3D content.

[bertt]

@astojilj main use case for now is getting something similar as build in CesiumJS:

https://geodan.github.io/pg2b3dm/sample_data/3dbag/sibbe/

Main features:

• Display 3D Tiles/glTF's

• Click on building to get attribute info (based on EXT_Structural_Metadata or b3dm header info)

• Combine with (custom) terrain, note we use 'depthTestAgainstTerrain' to occlude buildings behind hills

• Nice to have: style 3D Tiles in the client based on attribute, for example style on building year

[bertt]

Delaware buildings https://bertt.github.io/mapbox_3dtiles_samples/samples/standard/delaware/

[astojilj]

cc @jtorresfabra

[bertt]

q: Is there a sample of click on 3D Tiles (b3dm) and show attributes?

[bertt]

Dutch 3D Bag https://bertt.github.io/mapbox_3dtiles_samples/samples/standard/tienhoven/

Note: these are 3D Tiles 1.1 glb's (not b3dm's) containing EXT_Structural_Metadata for building attribute info.

[astojilj]

@bertt

Work on query render features support for Model Layer is in progress. However, we are not working on supporting 3rd party 3D tiles yet. Mapbox nodes encode ids in extras, for now:

[enersis-pst]

@astojilj is there a official roadmap? would be nice to know what will come :-)