Why buildings share same featureId

3D Tiles
1

i change the code as thas , and servel building have featureId=5,can i distinct each building

const tileset = await Cesium.Cesium3DTileset.fromIonAssetId(75343, {
  customShader: new Cesium.CustomShader({
                uniforms: {
          u_time: {
            type: Cesium.UniformType.FLOAT,
            value: 0,
          },
        },
    lightingModel: Cesium.LightingModel.UNLIT,
    fragmentShaderText: `
      void fragmentMain(FragmentInput fsInput, inout czm_modelMaterial material)
      {
          material.diffuse = vec3(0.0, 0.0, 1.0);
          material.diffuse.g = -fsInput.attributes.positionEC.z / 1.0e4;
      }
      `,
                vertexShaderText: `
          void vertexMain(VertexInput vsInput, inout czm_modelVertexOutput vsOutput)
          {
          int featureId = vsInput.featureIds.featureId_0;
if(featureId == 5){
                vsOutput.positionMC.y = vsInput.attributes.positionMC.y + 105.9 * sin(u_time);
                vsOutput.positionMC.x = vsInput.attributes.positionMC.x + 105.9 * sin(u_time);
}
          }
          `,
  }),
});
        const startTime = performance.now();
      viewer.scene.postUpdate.addEventListener(function () {
        const elapsedTimeSeconds = (performance.now() - startTime) / 1000;
        tileset.customShader.setUniform("u_time", elapsedTimeSeconds);
      });
2

is possible to make each building distinctive when generate 3dtiles,or is draft branch that possible to get metadata in shader

3

how each building feature generated?