Resolve a pass's pinned ladder depth (ViewState.ladderDepth) to a loop
bound: the number of rungs to load, clamped to [1, nLods], or null when
the pass is not pinned (absent, non-finite-and-not-Infinity, or below 1).
Infinity means "the whole ladder" and clamps to nLods. Shared by the four
geometry loaders so a fractional or over-long request cannot be interpreted
differently per geometry.
Resolve a pass's pinned ladder depth (
ViewState.ladderDepth) to a loop bound: the number of rungs to load, clamped to[1, nLods], ornullwhen the pass is not pinned (absent, non-finite-and-not-Infinity, or below 1).Infinitymeans "the whole ladder" and clamps tonLods. Shared by the four geometry loaders so a fractional or over-long request cannot be interpreted differently per geometry.