TLDR - floating point format has a great deal of precision near 0. Normally depth maps range from -1 to 1, but if you change that to 0 to 1 (and flip it) you c

TLDR - floating point format has a great deal of precision near 0. Normally depth maps range from -1 to 1, but if you change that to 0 to 1 (and flip it) you can utilize this extra precision.