Simplified calculation of DistanceToTop/Bottom to use the same code as VerticalExtrapolation.
Simplified calculation of DistanceToTop/Bottom to use the same code as VerticalExtrapolation.

iakovos-panourgias/fluidity,iakovos-panourgias/fluidity,jjo31/ATHAM-Fluidity,rjferrier/fluidity,jrper/fluidity,jrper/fluidity,jjo31/ATHAM-Fluidity,rjferrier/fluidity,rjferrier/fluidity,jrper/fluidity,iakovos-panourgias/fluidity,iakovos-panourgias/fluidity,iakovos-panourgias/fluidity,jjo31/ATHAM-Fluidity,jjo31/ATHAM-Fluidity,rjferrier/fluidity,rjferrier/fluidity,jrper/fluidity,jrper/fluidity,jjo31/ATHAM-Fluidity