czm_entireFrustum
An automatic GLSL uniform containing the near distance (x) and the far distance (y)
of the frustum defined by the camera. This is the largest possible frustum, not an individual
frustum used for multi-frustum rendering.
Like all automatic uniforms, czm_entireFrustum does not need to be explicitly declared.
However, it can be explicitly declared when a shader is also used by other applications such
as a third-party authoring tool.
Example
// GLSL declaration uniform vec2 czm_entireFrustum; // Example float frustumLength = czm_entireFrustum.y - czm_entireFrustum.x;