foveatedConeSize
Optimization option. Used when Cesium3DTileset.foveatedScreenSpaceError is true to control the cone size that determines which tiles are deferred. Tiles that are inside this cone are loaded immediately. Tiles outside the cone are potentially deferred based on how far outside the cone they are and Cesium3DTileset.foveatedInterpolationCallback and Cesium3DTileset.foveatedMinimumScreenSpaceErrorRelaxation. Setting this to 0.0 means the cone will be the line formed by the camera position and its view direction. Setting this to 1.0 means the cone encompasses the entire field of view of the camera, essentially disabling the effect.