Questions tagged [terrain]
The vertical and horizontal dimension of land surface
230
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Creating a heightmap from hillshade/radar data?
So there are several threads explaining how to create a hillshade map from DEM. Does anyone know of a method to do the opposite? Essentially all I have is unidirectional radar data which functions ...
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Service area depending on slope in QGIS
I am trying to create isochrons of walking depending on slope in QGIS. I am using the Service Area function and I have a slope assigned for each road. But I don't know how to determine the direction ...
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Most detailed surface map that can be produced from LiDAR data in ArcMap
I want to find old military trenches or at least to get an idea where they were, so that I can go to those areas and survey them.
I know the basic method of conversion from .lasd to elevation raster ...
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Polygons from a raster within an elevation range
In the image below I have generated some isolines starting from the terrain model and I have filtered them within a certain elevation range 800 - 1500m of elevation in QGIS.
But I would like to make ...
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Import a Map from gokml.net to QGIS
I want to import this map into QGIS:
http://gokml.net/maps#ll=48.093157,12.355834&z=6&t=t&s=14
It's the only way I found to display the Google Terrain Map without streets and labels.
If ...
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Convert a raster to show count of cells of a given relationship to each cell
Is there a tool (QGIS preferably), that will look at every raster cell, and compare it to neighbouring (1km) cells and populate the value with a value based on relationship.
Example (and indeed the ...
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Does the 0m elevation height of a Digital Elevation Model (Copernicus DEM) correspond to mean sea level?
I want to model future coastal flooding caused by sea-level rise under the latest IPCC scenarios at global scale. To this end, I use the Copernicus Digital Elevation Model (Copernicus DEM: https://...
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QGIS: Average of digital terrain model for a certain polygon
In one layer I have a lot of different polygons, which represent different areas. In addition I have downloaded a digital terrain model, which shows different slope percentages. All of this works, but ...
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Terrain Ruggedness index to polygon
I need to calculate ruggedness for a circular region extending x meters away from a central point. The TRI function in Terrain uses Wilson (2007) equation to calculate TRI for an entire raster
TRI <...
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What is the difference between TIN vs MESH vs TERRAIN in the context of GIS?
I couldn't seem to fully understand the differences between TIN, MESH, and TERRAIN dataset formats in GIS.
Per Wikipedia
a triangulated irregular network (TIN)1 is a representation of a
continuous ...
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How to determine the area size of a terrain for which I want to calculate its roughness
I want to calculate the wind speed on the ground for a specific location. In order to do so I will use the log wind profile. One of the input variables of this formula is the surface/terrain roughness....
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Terrain creation error using a GeoTIFF file with HEC-RAS 6.2 - "object reference not set to instance of object"
I am attempting to import a TIFF file created in QGIS, into HEC-RAS. I have a projection file as the SRS definition for HEC-RAS, which is derived from a shapefile that lines up with the spatial extent ...
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Band used for deformation estimation using In-SAR
Which polarization of SAR data (C-band - Sentinel-1A) shall I use to get a better deformation map of a mountain terrain - VV or HH?
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Calculate slope along line feature for line segments of equal elevation?
I would like to calculate the surface slope of a glacier in the Swiss alps.
In ArcGIS Pro this can be done using the Add Surface Information Tool. The output is a data table with the slope for each ...
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Terrain correction TerraSAR-X images
I am trying to perform terrain correction on a SAR image using GDAL.
I tried using simple gdalwarp, but the accuracy is not enough for me, so I decided to use:
gdalwarp -multi -wo NUM_THREADS=ALL_CPUS ...
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Error calculating aspect from DEM in R using raster/terra
I have a DEM file gathered using R. The raster and terra packages both have a function to calculate aspect, called terrain(). When using the terrain() function and the units="degrees" ...
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Converting aspect/direction raster from geographic degrees to arithmetic radians
I have a raster/grid representing e.g. terrain aspect or flow direction, coded in geographic degrees (0-360°, clockwise from the north). I would like to convert it in arithmetic radians (0-2π, ...
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Creating TIFF from Contour Lines
I need to quickly create a TIFF terrain (shades of grey terrain) from contour lines, or rather to create a GeoTIFF. In the past, I extracted vertexes from the contour lines and used that to create new ...
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Generate GLTF/OBJ models from quantized mesh (terrain) in CesiumJS?
I’m exploring ways to generate gltf / obj models from terrain mesh. My goal is to show 3d cut-fill volume calculation, something like the following -
I realized that I don’t need to DEM to generate ...
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How to query height of a given lat long coordinate from server side?
I need to some calculation with terrain surface, I use cesium but it works slow.
Cesium has a method sampleTerrainMostDetailed, it gives me height of given coordinates but it calculates height on ...
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Creating Contour Lines in QGIS 3.16 with a distance of 0,10 m
I would like to create Isohypses (Shape) ("Create contour lines") with a distance of 0,10m in a Digital Terrain Model (Shape File).
While processing the command, there are some errors poping ...
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Plan curvature in QGIS
I am trying to obtain plan curvature from a DEM. So far I have tried two methods from SAGA and GrassGIS plugins, however both do not seem to work and give errors.
Do you have a workaround suggestion?
...
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557
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Using Watershed Basin from SAGA in QGIS
I have a weird phenomenon going on in QGIS.
I want to derive a channel network and also the catchment areas using "watershed basin" from SAGA. In the end I want to have the flow direction ...
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How to interpret Terrain Ruggedness Index according to Wilson et al. (2007)?
Is there a categorical scale used to interpret values from the Terrain Ruggedness Index as calculated by Wilson et al. (2007), which is used in the raster library in R?
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Interpreting Ruggedness Index calculated from SRTM Tiles
I am looking for help interpreting the values from Ruggedness Index calculations.
I downloaded SRTM tiles using the SRTM Downloader plugin in QGIS. Then I calculated ruggedness from SRTM tiles in QGIS ...
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Intersection of an arbitrarily oriented 3D plane with a terrain DEM
In a nutshell
I'd like to compute the intersection of a 3D plane (defined by 3 points) and a terrain (given as a raster DEM GeoTIFF), and more particularly the part between two lines of that plane.
...
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Calculating direct solar radiation using QGIS and GRASS
I am using QGIS 3.16.8 and GRASS 7.8.5.
I would like to compare two places in my study area climatically. Since both are only a few 100 metres away, I assume that they only differed in terms of slope ...
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Reproducing terrain ruggedness index from the original paper example [closed]
I am not able to reproduce the terrain ruggedness index for the example used in the original Riley et. al paper.
The example is as follows:
When I try to reproduce the numbers in MS Excel I get ...
2
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1
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How to calculate the terrain profile in Profile Tools plugin
Now, I'm trying to calculate terrain slope(°) using pyqgis using below process.
Along the specific lines which I want to know the terrain profile, I generated the points using 'qgis:pointsalonglines'....
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An error occurred when using the terrain function in the production of Shiny dashboard
I am new to the 'shiny' package. I just try to produce an aspect map from the existing DEM data using the Shiny dashboard for training purposes. However, I faced the below warning in R and error in ...
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Grid from SAGA natural neighbor results in black grid
I'm new in QGIS and I'm following tutorials mainly on YouTube so I created a path in Google Earth then exported to kml which is converted to txt via GPS visualizer.
When added delimited layer it shows ...
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Why do I get negative values for the topographic position index (TPI)?
I run into issues, when trying to calculate the topographic position index (TPI).
I get values ranging from -13 to 17. And the resulting layer looks a bit odd, too:
If I understand it correctly, this ...
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Free or FOSS Elevation API for Heightmaps (image files) instead of elevation points
I'm coming from a Blender background, in which simple FOSS extensions exist (like BlenderGIS) that download SRTM/Aster Elevation Data and make a terrain based on this. I'd like to make something ...
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How to get elevation raster data at custom scales for a specific region?
I'm new to GIS and trying to obtain elevation data for a specific region, transformed to raster data with a custom cell size of 10 meters.
My first attempt was to download a TBDEM dataset from USGS ...
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How do I overlay vector data over a 3D terrain basemap?
I would like to create a map that is similar to the one found here: https://www.reddit.com/r/MapPorn/comments/lpo557/geological_map_of_north_america/ .
I'm thinking that you could replicate this with ...
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r.slope.aspect grass gis datum format on dx and dy analysis
I'm performing terrain analysis due to photovoltaic installation on QGIS with r.slope.aspect plugin. I'm interested in evaluate differently N-S slope and E-W slope based on the PV system I would ...
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Terrain Ruggedness Index (TRI) calculated in QGIS is approx 4 times that calculated in GDAL
When I calculate TRI using QGIS and GDAL tools for the same elevation DEM, I get results that are comparable between the two except that the absolute values in QGIS are approximately 4x that in GDAL. ...
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Selecting Terrain Dataset by elevation in ArcGIS Pro
I have added the Terrain Dataset to my project in ArcGIS Pro. I would like to select the areas which have an elevation above some threshold.
Eventually, I want to use this selection as a clipping mask ...
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NA values as result from Grass functions (r.slope.aspect, r.sim.water) in R
As the result from r.slope.aspect I get a raster with only NA values. r.param.scale works, but doesnt generate dx and dy maps, which I both need for r.sim.water function.
Code snippet 1 (initialize ...
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Using Aspect tool in QGIS
For my bachelor thesis in biology I´m working with QGIS 3.14 (Pi) and tried to create a layer where the slope aspect/expositon/exposure is presented. I´ve got a DTM1 on hands. There is this function ...
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3
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Terrain aspect similarity
I have a point data set with terrain aspect at the location of the points, measured in degrees. I want to compute the similarity of aspect between the points, e.g. 70° is similar to 90°. This is ...
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Lidar Dataset for Toe and Crest Detection
I have read a paper on Terrain Toe and Crest Feature Detection and Labelling forAutonomous Mining and started working on building the code for this. But I am unable to find the dataset used in the ...
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Extract terrain coordinates as seen from a viewpoint + FoV in a digital globe
Context
Every one working with photogrammetry or 3D knows what a depth image is. For example OpenCV defines a "depth map" from a stereo pair, e.g.:
where the darker a pixel is, the greater ...
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How do you export a 3d-model in QGIS to a file that can be read in Rhino?
I am really new to QGIS and haven't really gotten familiar with all the functions yet. I've made a 3D map/model in QGIS, and would like to export this in a file format so that I can use it as a ...
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2
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ee.Terrain.slope() output at wrong resolution after DEM mosaicking [closed]
I'm using the Google Earth Engine JavaScript API to do a terrain correction on Sentinel-1 imagery, as in Andreas Vollrath's work. However, I want to use a higher-resolution Canadian digital elevation ...
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Using ArcMap to build a Terrain DEM that looks exactly the same as a TIN built from the same point shapefile
I am attempting to replicate DEMs previously constructed as TINs in the Terrain format. Building a Terrain and a TIN out of the same point shapefile produces two maps that look extremely similar, but ...
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Getting from a USGS historical topographic map to a Unity terrain heightmap
Is it possible to start from a USGS historical topographic map and get to a Unity terrain heightmap? To see an example of the kind of historical topo map I am talking about:
Go to: https://ngmdb....
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Define Terrain/Elevation textfile data format
I have a program that can visualize terrain/elevation data but will only recognize files in the below format. It has the extension .map but it is not recognized by QGIS or GDAL so I believe it may be ...
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How do I "flood" a terrain in Cesium to represent a high water level
I am thinking about using a plane object to represent a water level by rendering it as a certain height above ground using Cesium. Is there any example code that
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Creating contour lines from DTM in PostGIS
Is there any possibility to compute contour lines from a raster DTM directly in PostGIS on a PostgreSQL database?
I have only found this solution based on points "Fast contour lines using plain ...