HeightReference() Scene/HeightReference.js 13 Represents the position relative to the terrain. Members staticconstantCesium.HeightReference.CLAMP_TO_GROUND : Number Scene/HeightReference.js 26 The position is clamped to the terrain. staticconstantCesium.HeightReference.NONE : Number Scene/HeightReference.js 19 The position is absolute. staticconstantCesium.HeightReference.RELATIVE_TO_GROUND : Number Scene/HeightReference.js 33 The position height is the height above the terrain.