Questions tagged [terrain]
The vertical and horizontal dimension of land surface
181
questions
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1answer
56 views
How accurate are Ordnance Survey MasterMap topography spot heights?
The spot heights in the Ordnance Survey MasterMap sample data over Exeter with feature code 15404 are presented as an integer value in metres. But how accurate are these spot heights? I had assumed ...
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0answers
18 views
Problem with weird values in DTM and not showing correct elevation
I am still new to Gis and don't know if I understand what is wrong.
I am working in a ocean survey program with point clouds. As seen on the picture the minimum depth is 1,92 and maximum 12,02. I ...
1
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0answers
36 views
Point/Area location of data in reference to geotransform of raster
I'm trying to understand how to interpret the position of pixel data within a GDAL raster, specifically as it applies to files containing height data. I'm create Triangular Regular Network (TRN) for ...
-1
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1answer
34 views
ArcGIS 10.X - DEM raster creation - Point to Raster vs. Terrain to Raster tools [closed]
I have a bunch of LiDAR data that I need to make a raster DEM & DSM from. From what I can gather my options are use the Point to Raster tool directly on the Multipoint feature or make a terrain ...
0
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2answers
123 views
Profile tool and GPS data in QGIS
I am trying to get elevation graph with the Terrain profile tool on my GPS data and can't get it to work. I have GPX file from a drive. I got this imported in QGIS. I have elevation data for each ...
1
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1answer
96 views
Cutting/ exporting multiple terrain profiles to CSV files with QGIS?
I am trying to cut multiple terrain profiles and export them to CSVs (individual or combined).
I have a shapefile of the profile lines, and a DEM to cut the profiles from.
I can do this manually ...
1
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1answer
138 views
My 3D polygons are being drawn below terrain
I'm importing a JSON file with polygons but I can't put them at the terrain ground level. They insist to be below the terrain.
I've created my own terrain server using DEM SRTM and the docker tumgis/...
1
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1answer
140 views
Creating 3D image from HGT files?
Is there any command line tool to create a 3D terrain from a DEM SRTM HGT file like this?
I mean, given a camera position, a HGT file and a satelite image.
EDIT 1
First try to adapt mdsumner's ...
2
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0answers
47 views
VRM tool QGIS error generating layer
I am trying to use the VRM tool in QGIS of the SAGA package. Every time I get an error message:
layers could not be generated.
I tried different input rasters (DEM and DTM) and kept other settings ...
0
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1answer
59 views
Aligning shapes to terrain in CityEngine?
I have a problem. As soon as I click "Align shapes to Terrain", my shapefile rectifies and falls down the edge.
In the first picture(Border_Issue1) you can see that all shapefiles have the right size,...
1
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1answer
53 views
Integrating sea level curve data in a bathymetric grid
I am attempting to apply these data recording where sea-level was in the Gulf of Mexico (in meters below mean sea level) over the past 20,000 calendar years at a 500-year resolution in ArcMap:
What ...
1
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1answer
104 views
r.surf.area command of GRASS GIS is giving a very small area
I am a beginner to GIS systems and am trying to calculate the surface area of a dem using r.surf.area command of GRASS GIS. The surface area it is giving me is unacceptable as it is very small. It is ...
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1answer
54 views
Creating DEM raster from ASCII .xyzi LiDAR [duplicate]
I was passed along some LiDAR data that is in .xyzi ASCII format. I am having trouble figuring out a way to build a TIN or DEM from this data. I brought it in using "ASCII 3D to feature", and ...
2
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1answer
222 views
Converting DEM (TIFF) files to terrain files?
I want to create an app to show 3D using ol-cesium. In ol-cesium example it use cesium terrains, But I want to do it with my DEM files.
How can I convert my DEM (TIFF) files to terrain files?
1
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1answer
103 views
Finding glider reachable area / catchment area with custom slope?
I'd like to produce maps for gliders in mountains.
I'm looking to display the reachable area by a glider taking off from a given point (obviously with the corresponding DEM).
For a first approach I'...
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0answers
30 views
Weighted averages: accounting for cell size
I'm a non-geographer using ArcMap 10.6.
I have a similar question to the two asked here: Weighted averages: accounting for grid cell surface variation in proportion to the cosine of its latitude
I ...
1
vote
1answer
432 views
Using terrain correction in SNAP sentinel 1 toolbox removes all the values
I am new to SAR image processing, I have a SAR sentinel 1 dataset downloaded from ESA site: S1A_IW_GRDH_1SDV_20190314T030905_20190314T030930_026328_02F196_2EC3
I am trying to do terrain correction ...
2
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1answer
64 views
Nested loop and terrain analysis R
I have a raster stack with 11 layers that I am running through a triply nested lapply(). I expect 44 layers to be returned, but I'm only seeing 4!
Reproducible example:
# Load packages
library(...
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1answer
67 views
City Engine: Align Terrain to Shapes - Purpose?
What is the purpose of aligning the terrain to shapes, if I have already aligned my shapes to the terrain?
In my understanding, the terrain is a reference surface, and therefore I wouldn't want to ...
1
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1answer
399 views
Merging several .hgt files into one
I'm currently struggling on trying to combine several .hgt files with different software. I can get the 4 tiles into any kind of software but my issue is exporting the file back to .hgt file.
I've ...
4
votes
2answers
512 views
How do I calculate the Terrain Ruggedness Index for each county in the United States in R?
I have a shapefile of US counties and high-resolution elevation data that spans the entire contiguous United States. My goal is to calculate a terrain ruggedness index for each county. The functions (...
2
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0answers
98 views
Importing several LiDAR (.las) files in GRASS using v.in.lidar?
I'm building a DEM of a terrain in GRASS and have 48 LiDAR (.las) files. I know I can do this by using
r.in.lidar (including the list of files as a .txt) and then r.fillnulls
However, I want to ...
0
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3answers
485 views
Clip tool in ArcGIS Pro not working?
I'm trying to clip "Terrain" raster I downloaded from the portal (https://www.arcgis.com/home/item.html?id=58a541efc59545e6b7137f961d7de883) in the shape of a polygon (a country's boundaries) by using ...
2
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0answers
227 views
Cannot access Terrain Server for Cesium
I'm trying to follow a series of tutorials:
visualizing-terrains-with-cesium-ii
visualizing-terrains-with-cesium
Some other useful posts here:
Unable to serve Cesium Terrain files
error-in-...
1
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1answer
260 views
How should I interpret R terrain/slope output in degrees?
I'm calculating the average land gradient (in degrees) in Brazil and I do not know how to interpret the results.
As I'm calculating the slope in degrees, 0.25 is 0.25 degrees, 25 degrees or should I ...
0
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1answer
35 views
Calculating Viewshed of a region rather than a point [closed]
There are various calculations to find the viewshed of a point and all of them have different runtimes. the fastest is the calculation of line of sight angle and compare with upcoming cells.
But what ...
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0answers
43 views
Erroneous contour polygons in QGIS 3
I have a global DEM and try to calculate contour polygons for 4 different heights in QGIS.
In the first image below, you can see the colored DEM (white = lowest; yellow = higher; orange = highest) as ...
1
vote
2answers
608 views
“Relief” function from the Raster Terrain Analysis plugin in QGIS 3.0
I am using QGIS 3.0, where I can't find the Raster Terrain Analysis plugin.
I am under the impression that the plugin was embedded into the QGIS 3.0 version, as under "Raster --> Analysis" there ...
2
votes
1answer
138 views
Extracting Road Terrain Properties using DEM / LIDAR
I want to extract following road terrain data from DEM but I'm not sure if its possible. Can i extract these attributes using LIDAR if not DEM ?
These are the data fields I need:
Horizontal curve ...
2
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0answers
64 views
Converting Surface Model to Elevation Model?
Is there a way to convert a digital surface model (DSM) to a digital elevation model (DEM) in QGIS?
Surface models contain lots of noise (e.g. trees, buildings) when I only want to show the ground. ...
1
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1answer
524 views
cesium quantized mesh generator
We are trying to develop pur own quantized mesh generator and visualize these terrain tiles on CesiumJS. As an input we use SRTM data that belongs to north parth of TURKEY. We generate contours on DEM,...
5
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0answers
77 views
Using the height of river to approximate its extreme flood boundaries - terrain analysis in QGIS?
Using QGIS I'm trying to analyse an area/DEM with this criteria: - heights 10 meter above the river-centerline in both sides of river.
I can do it with the calculation of contours (2m) from DEM and ...
5
votes
0answers
362 views
Using QGIS 2.14 to creating a evenly distributed grid of points, spaced 500m apart, that takes terrain into account [closed]
I am using QGIS 2.14 (Essen Version).
I need to create a grid of points within a given area so that each points 500m across the ground from any other point. At these points trail cams will be placed,...
2
votes
2answers
448 views
Clipping terrain in ArcMap?
Is there a way to clip a terrain in ArcMap, or make sure it doesn't exceed a certain geographical extent area in the first place?
After creating my terrain from a multipoint file it looks like this:
...
1
vote
1answer
673 views
Interpreting results in legend, SAGA GIS or QGIS? [closed]
Can somebody explain to me what units of measurement do I get in the results of analysis, ground morphometry in SAGA GIS software or through a plugin in QGIS?
for example:
Terrain ruggedness index (...
1
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0answers
75 views
Esri Terrain-Tools v1.1 Sky Tool Cannot Save File
I am trying to use Esri Terrain-Tools v1.1 to create a hillshade from either a 90 m SRTM DEM or 30 m DEM. I have tried saving this to a file geodatabase (FGDB) and .tif. In both cases the error ...
5
votes
2answers
753 views
Using slope and total height for terrain analysis in QGIS?
Using QGIS I'm trying to analyse an area/DEM with these two criteria:
-Even sloping terrain steeper than 1:20 and total slope height > 5 m.
Finding areas with slope of 1:20 (5% slope) could be done ...
0
votes
1answer
61 views
Can I created a DEM or digital surface model with high resolution image
I have VHR imagery, 5 cm pixel, and I want to create a DEM but this image has high trees and when I take my model I cant take a real elevation because DEM is not the height of the terrain.
Could I ...
0
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0answers
40 views
No cell value in raster file [duplicate]
I downloaded a .tif raster file from opentopography.org. It's an Alos (AW3D30
) topography file showing mountainous terrain in Sweden.
On the very right the file contains terrain, and on the left a ...
1
vote
1answer
64 views
Finding Rocky Outcrops
I've been asked by one of my users if it's possible to find "Rocky Outcrops" in an area. They don't really have a definition for what that means, it's a very open ended question!
My feeling is that ...
1
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0answers
82 views
Measuring true length of polyline over terrain in QGIS? [closed]
I use QGIS for a variety of mapping purposes and also for managing UAV/drone data. I need to calculate the true length of a mapped fence over varying terrain for which i have a detailed DEM.
Is this ...
1
vote
1answer
114 views
Changed aws terrain datasets
I noticed that the structure and size of the file was changed
pattern https://s3.amazonaws.com/elevation-tiles-prod/geotiff/{z}/{x}/{y}.tif
example https://s3.amazonaws.com/elevation-tiles-prod/...
1
vote
2answers
422 views
CityEngine: aligning a shape to terrain
I have three layers: 1-Parcels 2-Buildings 3-DEM
I imported them all into CityEngine and I aligned parcels and Buildings to Terrain (DEM).
I noticed that, in large parcels (see Figure 1), some ...
1
vote
1answer
1k views
Terrain correction / Orthorectification with gdal
Since MODIS Imagery Orthorectification (Open Source) had no answer, I will try to get one here with a similar problem:
I got some raster datasets with GCPs in lat/lon, but without height information. ...
0
votes
1answer
207 views
Use LatLng Double to query GeoTiff in geotrellis (scala)
I am currently trying to read bigtiffs into geotrellis in Scala to read single band terrain geotiffs. I can load them successfully, and query data/access CRS and extent info by
val tiffPath: String =...
1
vote
1answer
45 views
Creating ArcGIS terrains using ModelBuilder?
I'm trying create a terrain using ModelBuilder but with "Create Terrain" there is no where to specify SFTypes and when the model is run it give the error:
The Terrain definition is incomplete or ...
1
vote
0answers
922 views
Cartopy image tiles - determining possible zoom level in advance?
In Cartopy I'm using an image tile like so:
terrain_tile = cimgt.StamenTerrain()
ax.add_image(tile, zoom)
By default I've set the zoom level to 14 and that works perfectly for my first test case.
...
4
votes
1answer
223 views
QGIS: Terrain accessibilty in hours/days usind DEM/CSV data
I am an Archaeologist. I am interested in settlement dispersal and land use strategies in late antiquity and early middle ages.
Therefore, I want to analyze a certain terrain by:
- least cost ...
9
votes
1answer
132 views
How to style rocky coast?
I've got a bunch of data from LINZ which includes rocky areas. Is it possible to style them as they do (see picture)? It's a fairly standard style in large scale maps so I hoped it would be simple!
I'...
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0answers
38 views
Interpret terrain type from height data and/or geolocation
I have downloaded a large subset of the STRMGL1 Dataset, and have further split each entry down into 5km by 5km tiles. I now need to start classifying each tile by terrain types. Are there any ...
