Questions tagged [terrain]
The vertical and horizontal dimension of land surface
186
questions
2
votes
1answer
43 views
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....
1
vote
0answers
37 views
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 ...
1
vote
0answers
17 views
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
2
votes
1answer
65 views
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 ...
0
votes
1answer
39 views
What is meaning of scale on x and y axis of image using matplotlib
I am finding elevation of a region using richdem.
Can somebody tell me what is the meaning of the scale which is on the x and y axis of the image?
import os
import numpy as np
import matplotlib
...
1
vote
0answers
41 views
DSM results from WebODM are not correct [closed]
I am new to WebODM and I am trying to generate DSM and Orthomosaic images using default settings in WebODM.
The Orthomosaic image is correct by providing GCP but the DSM file is having inaccurate ...
0
votes
1answer
63 views
Digital elevation model - getting files in the .DEM extension
Could you tell me from where can I get the Digital Elevation Model data in the .DEM file extension?
The option for QGIS here:
https://www.qgistutorials.com/en/docs/working_with_terrain.html
shows the ...
1
vote
1answer
69 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 ...
0
votes
0answers
21 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
vote
0answers
69 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 ...
-2
votes
1answer
40 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
votes
2answers
299 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
vote
1answer
190 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
vote
1answer
254 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
vote
1answer
188 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
votes
0answers
57 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
votes
1answer
71 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
vote
1answer
57 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
vote
1answer
132 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 ...
0
votes
1answer
80 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
votes
1answer
332 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
vote
1answer
105 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'...
1
vote
1answer
602 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
votes
1answer
94 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
votes
1answer
71 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
578 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
643 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
124 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
3answers
957 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
votes
0answers
293 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
361 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
38 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
48 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
747 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
155 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 ...
3
votes
0answers
83 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
612 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
votes
0answers
87 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
368 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
542 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
807 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
vote
0answers
81 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
908 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
76 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
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
67 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
85 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
138 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
466 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. ...
