An example tileset that uses the Implicit Tiling to represent a small, sparse quadtree.
The quadtree has 6 available levels, and each subtree has 3 levels. There are 32 tiles available in level 5. Each of these tiles has a content, which is a simple glTF asset as a GLB (glTF binary) file that just consists of a portion of the unit square that corresponds to the extent of the respective tile. No other tiles - except for the ones that have content, and their respective ancestors - are available.
const viewer = new Cesium.Viewer("cesiumContainer");
// Create the tileset in the viewer
const tileset = viewer.scene.primitives.add(
await Cesium.Cesium3DTileset.fromUrl(
"http://localhost:8003/1.1/SparseImplicitQuadtree/tileset.json",
{
debugShowBoundingVolume: true,
}
)
);
// Move the tileset to a certain position on the globe,
// and scale it up
const transform = Cesium.Transforms.eastNorthUpToFixedFrame(
Cesium.Cartesian3.fromDegrees(-75.152408, 39.946975, 1)
);
const scale = 15.0;
tileset.modelMatrix = Cesium.Matrix4.multiplyByUniformScale(
transform,
scale,
new Cesium.Matrix4()
);
// Zoom to the tileset, with a small offset so that
// it is fully visible
const offset = new Cesium.HeadingPitchRange(
0,
Cesium.Math.toRadians(-67.5),
40.0
);
viewer.zoomTo(tileset, offset);The following image shows the 6 levels of the tileset. Tiles that are available contain a 1 and are shown in green. Tiles that are not available contain a 0 and are shown in red. Cells that contain content are marked with 1+ (only in level 5).
The JSON parts of the .subtree files and the availability information that is stored in the binary buffers is summarized in subtreeInfo.md.