Questions tagged [terrain]
The vertical and horizontal dimension of land surface
2
votes
1answer
23 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(...
0
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0answers
22 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
vote
1answer
44 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
103 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
votes
0answers
47 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
votes
1answer
47 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 ...
1
vote
0answers
25 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
vote
1answer
41 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
votes
1answer
28 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 ...
0
votes
0answers
38 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 ...
0
votes
0answers
10 views
Creating terrain polygon buffer from line using ArcMap? [duplicate]
I have a line in a steep hill, and need a 400 meter buffer on each side of the line. I know (roughly) how to create buffer on a point, but not a line.
Can someone help me here?
0
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0answers
40 views
Is there a way to linear reference a line in QGis [duplicate]
Iv'e seen a number of plugin's that do things like create grids of points and such like, but what I need to do ideally is to create a line of points that follows a line geometry, and then drop those ...
1
vote
2answers
182 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
58 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
votes
0answers
48 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
vote
1answer
207 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,...
4
votes
0answers
54 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 ...
0
votes
0answers
18 views
Ruggedness Index appended to point data [duplicate]
I'm working with two key files, one is a ruggedness Index raster built from a DEM raster file and the other is point data for roughly 100k points.
What is the simplest method available using open ...
0
votes
0answers
42 views
Exclusion zones (for trees/buildings) in QGIS Viewshed
Is there a way to set up an 'exclusion zone' in a viewshed in QGIS?
For example, I want my viewshed to take into account a large block of screening trees in it's calculations, to see how the ...
5
votes
0answers
343 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
200 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:
...
0
votes
1answer
338 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 (...
0
votes
0answers
86 views
Error in loading terrain files (.terrain)
I can't load the terrain file to the cesium. Now I will describe how I did it step by step. Hope this will help you find out where I went wrong.
STEPS:
Basically, I am following the tutorial in this ...
1
vote
0answers
49 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
508 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 ...
-1
votes
0answers
30 views
Terrain obstruction between 2 points
I'm trying to figure out the amount of terrain obstruction there is in a straight line between two points.
I used the Terrain Profile plugin in QGIS to get an elevation graph against distance, and I'...
0
votes
1answer
53 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
votes
0answers
37 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
52 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
vote
0answers
64 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
78 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
267 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
0answers
604 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
136 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
33 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
564 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
205 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
127 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'...
1
vote
0answers
34 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 ...
2
votes
1answer
370 views
Extruding building heights from 3D terrain model creates sloped buildings
How can i prevent sloped buildings when I extrude building footprints over sloped terrain? I am using FME to drape 2D features over terrain (SurfaceDraper), then using the Extruder transformer to ...
0
votes
0answers
48 views
Slope Analysis from Raster and Contour Lines do not match QGIS [duplicate]
Having run the slope analysis using Terrain Analysis with a percentage output, I found that my outputs ranged from 0 to 0.013, with virtually all land ranging from a slope of 0 to 0.00326. Measuring ...
0
votes
1answer
246 views
Contour TIN Interpolation
I'm attempting to interpolate the NU national grid square of Ordnance Survey's terrain data (10m intervals). If I interpolate with IDW, I encounter no issues and the raster pixels are square in shape ...
0
votes
2answers
127 views
Slope between max and min values of a defined area within a DEM
Say I have a DEM raster. I then also I have a set of polygons in which I would like to know the slope between the max and min DEM values of any given polygon. If my thinking is correct, I could ...
2
votes
2answers
666 views
Creating a map highlighting areas of potential visibility of a high structure
The end goal is to add a point which will represent a mast/pylon of x height and for QGIS to generate polygons for the surrounding area which will have direct visibility of the top of the structure ...
1
vote
2answers
391 views
Algorithm for smoothing DEM without losing max and min elevations
I am looking for a method/algorithm for smoothing a DEM raster similiar to something like lowpassing, however I want to keep the highest and lowest points, resp. peaks. Latter often are only ...
4
votes
1answer
1k views
DTM extraction of tree heights
I need to classify tree heights in a DSM of a slope-y terrain. It´s not a forest but several individual / detached trees. In a plane terrain it won´t be an issue but in that uneven terrain I need ...
1
vote
0answers
151 views
Buffering based on topography in ArcGIS Desktop?
I need to do a buffer based on the real terrain.
Like 500 meters from a polyline on all sides.
I have DEM (SRTM) of the terrain.
Is there a way to do that?
7
votes
2answers
752 views
Slope, in which direction?
I have a dilemma? I work with a slope terrain. Slope field is done by a percentage of 10%. My question is, in which direction is oriented this pixel, or any pixels? It is important to know to what ...
0
votes
1answer
742 views
Open source solution to convert terrain data to collada?
I am exploring how to convert terrain information (DTED, SRTM, etc) to a 3D mesh file. Collada is preferrable as it is very compatible.
I have read this: Converting dem and geotiff to collada model ...
1
vote
0answers
137 views
Smoothing relatively flat DEM for terrain and hydrologic analysis
I'm trying to do some terrain and hydrologic analysis from a 1/3 arcsecond DEM that I downloaded from the USGS National Map website. The issue I'm having is that the area in question is central ...
