Tool Terrain Map View
This tool allows one to create different terrain visualisations from an elevation dataset:
* Topography: a simple map with an analytical hillshading of the terrain
* Morphology: a map which visualizes the terrain by combining positive and negative openness (Yokoyama et al. 2002) with terrain slope in a single map. In contrast to conventional shading methods this has the advantage of being independent from the direction of the light source.
References:
Yokoyama, R. / Shirasawa, M. / Pike, R.J. (2002): Visualizing topography by openness: A new application of image processing to digital elevation models. Photogrammetric Engineering and Remote Sensing, Vol.68, pp.251-266. online at ASPRS.
- Author: Copyrights (c) 2014 by Volker Wichmann
- Menu: Visualization|Grid
Parameters
| Name | Type | Identifier | Description | Constraints | |
|---|---|---|---|---|---|
| Input | DEM | Grid (input) | DEM | Digital elevation model. | - |
| Output | Shade (*) | Grid (optional output) | SHADE | The shaded DTM. | - |
| Openness (*) | Grid (optional output) | OPENNESS | The difference of positive and negative openness. | - | |
| Slope (*) | Grid (optional output) | SLOPE | The calculated terrain slope [radians]. | - | |
| Contours (*) | Shapes (optional output) | CONTOURS | The generated contour lines. | - | |
| Options | Grid system | Grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Method | Choice | METHOD | Choose the map type to generate. | Available Choices: [0] Topography [1] Morphology Default: 0 | |
| Radial Limit | Floating point | RADIUS | Radial search limit for openness calculation. | Minimum: 0.000000 Default: 1000.000000 | |
| Contour Lines | Boolean | CONTOUR_LINES | Derive contour lines. | Default: 1 | |
| Equidistance | Floating point | EQUIDISTANCE | Contour lines equidistance [map units]. | Minimum: 0.000000 Default: 50.000000 | |
| (*) optional | |||||
Command-line
Usage: saga_cmd grid_visualisation 8 [-DEM <str>] [-SHADE <str>] [-OPENNESS <str>] [-SLOPE <str>] [-CONTOURS <str>] [-METHOD <str>] [-RADIUS <double>] [-CONTOUR_LINES <str>] [-EQUIDISTANCE <double>] -DEM:<str> DEM Grid (input) -SHADE:<str> Shade Grid (optional output) -OPENNESS:<str> Openness Grid (optional output) -SLOPE:<str> Slope Grid (optional output) -CONTOURS:<str> Contours Shapes (optional output) -METHOD:<str> Method Choice Available Choices: [0] Topography [1] Morphology Default: 0 -RADIUS:<double> Radial Limit Floating point Minimum: 0.000000 Default: 1000.000000 -CONTOUR_LINES:<str> Contour Lines Boolean Default: 1 -EQUIDISTANCE:<double> Equidistance Floating point Minimum: 0.000000 Default: 50.000000