1. Can b3dm tiles be blank? for example ,content is empty,but it has boundingvolume and geometrierror. When I use Add refine for LOD ,some level tile have no data, but sub-level have data. i found cesium can't show data as LOD, instead all levels are shown.
2. What's the define and formula of the geometricerror? how to set value on top level,root ,children ? what does value "0" stand for?
A b3dm won’t be blank, but you can have empty tiles in tileset.json that have bounding volume and geometric error, but no content.
ADD means that all levels of show simultaneously. I think you might want to use REPLACE instead.
The geometric error is a value that controls when a tile’s children get rendered and it doesn’t have a specific formula since it is pretty context dependent. As an example, for a point cloud stored as an octree the geometric error might start at a large value and divide in two for each level. For building data, the geometric error might be the height of the tallest building in its children’s tiles. A value of 0.0 typically means that the tile has no children and does not refine further.
NO,I mean that I have two level , top level geometricError is 100 , the child level geometricError is 10 ,and refine is add.
the child level data is shown when top level is empty, at geometricError 100 distance.
the child level data is not shown when top level is not empty, at geometricError 100 distance.
that’s what it should be？ I guess at geometricError 100 ,it should show no data,when top level is empty.
Ok I think I see now. You’re right, the child tile should not get shown if the parent is empty and the distance is far enough away. Would you mind sending me the tileset so I can confirm the problem?