SAGA.ta_lighting.0: Analytical Hillshading

This tool performs an analytical hillshade computation for an elevation grid. The 'Standard' method simply calculates the angle at which light coming from the position of the light source would hit the surface. This method can produce angles greater than 90 degree. With the second method all values are kept within the range of 0-90 degree. It can be enhanced with shadowing effects, where shadowed cells will be marked with a value of exactly 90 degree. 'Shadows Only' creates a mask for the shadowed areas and sets all other cells to no-data. 'Combined Shading' takes the values of the standard method and multiplies these with the normalized slope. 'Ambient Occlusion' is based on the concepts of Tarini et al. (2006), but only the northern half-space is considered here.

Inputs

Élévation

format
href
Please set a value for ELEVATION.

Shading Method

string

Sun's Position

string

Direction of the light source, measured in degree clockwise from the North direction.

number

Height of the light source, measured in degree above the horizon.

number

Day

string

Hour

number

The terrain exaggeration factor allows one to increase the shading contrasts in flat areas.

number

Unit

string

Choose 'slim' to trace grid node's shadow, 'fat' to trace the whole cell's shadow. The first is slightly faster but might show some artifacts.

string

Number of sample directions for ambient occlusion. Divides azimuth range (270 to 0 to 90 degree) into sectors. Declination (0 to 90 degree) is divided in (Number of Directions / 4) sectors.

integer

Radius used to trace for shadows (ambient occlusion) [map units].

number

Outputs

The angle between the surface and the incoming light beams, measured in radians.

format
transmission

Execution options

successUri
inProgressUri
failedUri

format

mode

Execute End Point

View the execution endpoint of a process.

View the alternative version in HTML.

http://demo.mapmint.com/ogc-apihttp://localhost/ogc-api/localhost/ogc-api/processes/SAGA.ta_lighting.0.html
Last modified: Sat Feb 19 15:43:34 CET 2022