Calculating the percent of the wetted width shaded by banks and vegetation

Source: R/shade_calc.R

Translation of r_shade.m

shade_calc(
  delta,
  solar_altitude,
  bottom_width,
  BH,
  BS,
  WL,
  TH,
  overhang,
  overhang_height
)

Arguments

delta

difference between the sun and stream azimuth (sun-stream)
solar_altitude

Solar altitude (radians) calculated by solar_c.R
bottom_width

#ADD DETAILS
BH

Bank height
BS

Bank slope
WL

Water level
TH

Tree height
overhang

Effectively canopy radius
overhang_height

height of the maximum canopy overhang (think canopy radius)

Value

Returns percent of the wetted width shaded by the bank and by vegetation