Use Coordinate Origin

[micahpw]

Using deck.gl "coordinateOrigin" feature will enable smoother rending and lower jitter when panning and zooming. This has to do with floating point precision getting rounded near boundaries but having each tile/layer have a relative origin enables higher fp32 precision and lower jitter.

[micahpw]

// Single layer, camera-relative origin
function GridSightMap({ viewState, transmissionLines }) {
  const layers = [
    new PathLayer({
      id: 'transmission-lines',
      data: transmissionLines,  // All lines in one GeoJSON
      getPath: d => d.geometry.coordinates,
      getColor: d => getColorForFlow(d),
      getWidth: 2,
      
      // Key: coordinate system with offset support
      coordinateSystem: COORDINATE_SYSTEM.LNGLAT,
      
      // Origin tracks camera - updated each frame
      // This is a uniform, NOT per-vertex, so no buffer rebuild
      coordinateOrigin: [viewState.longitude, viewState.latitude],
      
      // Ensure we're using the offset projection
      extensions: [],  // project32 is default, handles offsets
    })
  ];
  
  return <DeckGL viewState={viewState} layers={layers} />;
}

// deck.gl internally does:
//   localPos = worldPos - coordinateOrigin  (small numbers!)
//   clipPos = viewProjection * localPos     (fp32 is fine)