Hillshade (terra shade) — Hillshade • rmorie

\(\cos z \cos s + \sin z \sin s \cos(\phi - a)\) with sun zenith \(z = 90 - angle\).

Usage

Hillshade(slope, aspect, angle = 45, direction = 315)

Arguments

slope, aspect: Radians (TerrainIndices).
angle: Sun elevation (degrees).
direction: Sun azimuth (degrees).

Value

Matrix.

Examples

Hillshade(matrix(0), matrix(0))
#>           [,1]
#> [1,] 0.7071068