The vertical and horizontal dimension of land surface

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24
votes
4answers
5k views

How to calculate terrain Curvature?

I have an elevation raster and I would like to get some basic terrain variables, such as slope, ruggedness, aspect or curvature. The problem is that I don't seem to have the possibility to calculate ...
23
votes
8answers
2k views

How to generate a random but believable digital elevation model?

Is there a way to generate a DEM, programatically or otherwise (arcpy or R?), that will feed into ArcGIS for further spatial analysis? Perhaps this needs to be broken down into smaller incremental ...
19
votes
7answers
7k views

Are there open access terrain tiles with a permissive license like OSM?

Are there open access terrain pyramidal map tiles with a permissive usage license like OpenStreetMap's? I'm building aviation-related maps with Polymaps and need a good raster basemap. The Google ...
18
votes
5answers
5k views

Given a terrain, how to draw the stream flow path?

Assuming I have a terrain, as usual the terrain has ridges, creeks and all the characteristics that you can find on a real life map. Water flows from the top of the mountain into lower area, the path ...
9
votes
2answers
1k views

TRI, TPI, or Roughness

I am working on a site selection projection where I will be unable to perform any in situ observations. A key component of the selection process is the ruggedness of the underlying terrain. I plan ...
9
votes
6answers
1k views

seeking “Available Sky” implementations

I'm looking for implementations of an algorithm called "Available Sky". ArcGIS (Spatial Analyst or GRID) is preferred, but solutions in GDAL, SAGA GIS or others are perfectly acceptable. The ...
9
votes
5answers
29k views

Creating profile cross-sections in ArcGIS Desktop?

Because the default 'Profile Graph' tool was not sufficient, I wrote a custom VBA script that creates scaled and exaggerated profile cross-sections in ArcGIS but I need more features: Visualize more ...
8
votes
2answers
2k views

Floodplain generation given river section polylines, flood level elevation points and a DEM of the land surface [closed]

I am looking to generate flood plain polygons to represent 20 and 100 year flood zones, in the most accurate and efficient way possible, given the following datasets: 1) River cross section polylines ...
7
votes
1answer
12k views

Which is better, DEM or Triangles (TIN/Terrain)

Which is better DEM or TIN? What are the benefits/negatives of each?
7
votes
4answers
582 views

Which ArcGIS product gives full 3D terrain navigation and (flight) simulation?

I looked at the ArcGIS ESRI website and find that 100% of the screenshots depicts a 2D map with at most relief shading. Is there any product ArcGIS or not that gives real 3D terrain visualisation ...
7
votes
1answer
2k views

Bringing GIS data into Minecraft

A little off the beaten path...: Denmark has built a 1m:1block Minecraft World using real GIS data. Here's the home page, in Danish: http://gst.dk/emner/frie-data/minecraft/, and an ArsTechnica ...
6
votes
3answers
2k views

Where I can find world terrain data?

I need free terrain data for the whole world which I can import into TileMill. Is there some source where I can download them? Thank you.
6
votes
1answer
212 views

In hydrologic terrain analysis is there a difference between “pits”, “depressions”, and “sinks”?

In hydrologic terrain analysis is there a difference between "pits" and "depressions"? For instance, Planchon and Darboux (2002) state The usual numerical methods for removing the depressions of ...
6
votes
3answers
2k views

Finding elevation differences between adjacent pixels in ArcGIS Desktop?

Is there a way to determine what the difference in elevation is between two adjacent pixels? I am using an SRTM DEM to map faults. I am using the vertical error (>16m) as a criterion for the ...
6
votes
2answers
366 views

Auto Balancing in EarthWork

I am not sure whether this question belongs here. I think it belongs more to Geo-technical, but anyway, I just give it a shot. During earthwork development, earth terrain has to be cut ( if the ...
6
votes
2answers
695 views

Problem Visualizing 3D Terrain Model - USGS DEM

I recently downloaded a GeoTIFF 1 arc second from the USGS National Map Viewer. I added the raster to ArcScene and attempted to visualize the data in 3D. I set the Base Height to Floating on a ...
6
votes
2answers
1k views

Has (ESRI) TIN been superseded by Terrain Dataset?

I've had version 10 for a few months but it wasn't until today that I really tested the 3D Analyst extension. (Other then visualizing data) I already noticed a lot of changes; a number of tools have ...
5
votes
3answers
519 views

How do I use the Terrain with Labels basemap in the Map constructor

Seems like all the other basemaps can be used in the esri.Map() constructor, but this one doesn't have a corresponding entry in the list of acceptable values. I've tried just "terrain", and it didn't ...
5
votes
1answer
223 views

Cartographic technique for detailing a 'Focus Area'

I'm working on updating a planning document. Whoever was in charge of cartography last time around used a great technique to identify and showcase focus areas (where to focus money and effort for ...
5
votes
1answer
421 views

Generating a vector contour map of fictional terrain

Originally I had asked this on the Graphics Design SE but after some realization of the question I was asking, it's probably better to ask it here. I'm making a fantasy world map in illustrator that ...
4
votes
6answers
3k views

shadow simulation from buildings [duplicate]

is it possible to use hillshade function in ArcMap to calculate shadow areas of buildings or simulate shadows of buildings, using DSM of the buildings and the sun angle and azimuth?
4
votes
2answers
192 views

Software for amateur topographic surveys

I'm interested in doing rough topographic surveys using my tripod-mounted Brunton transit compass for azimuth readings and laser rangefinder (and maybe an optical level), so obviously going to be much ...
4
votes
1answer
2k views

How to create contours from smoothed DEM instead of using Terrain to Raster?

I'm fairly new to working with lidar and have been assigned the task of creating 2ft contours for the entire county using USGS-provided lidar tiles. Is there a significant difference in the accuracy ...
4
votes
2answers
716 views

How to create a raster tiff (dem / heightmap) from a mesh of xyz points?

I have to create a terrain heightmap(raster tif preferably) from mesh of xyz ungridded points(in geographical coordinates), I tried taking min and max of bbox of mesh and making width & height by ...
4
votes
0answers
73 views

QGIS Profile Tool shows no profile

I have installed and followed the process to produce an elevation profile from the Route Profile plug-in in QGIS, but for some reason I am getting no profile to appear. The grids are from OS ...
4
votes
0answers
37 views

Cropping EUDEM with GDAL creates zig-zag terrain

I have downloaded EUDEM (20 Gb) from http://www.eea.europa.eu/data-and-maps/data/eu-dem#tab-original-data When I try to crop it by GDAL using: gdalwarp -dstalpha -of EHdr -crop_to_cutline -cutline ...
3
votes
4answers
6k views

Can I convert ESRI Grid (DEM) raster to USGS DEM?

There is a tool for DEM to Raster in ArcGIS but I need to convert my ArcGIS DEM rasters (mostly LiDAR) into USGS DEM. The idea is to import this DEM into Sketchup and create a "sandbox" TIN surface ...
3
votes
2answers
348 views

Where I can find real world data for triangulation? [duplicate]

I want points for practicing triangulation algorithms. Just points with coordinates [X,Y] and elevation [Z] of real world terrain. I can use Google Maps Elevation API, but there is no method how to ...
3
votes
2answers
1k views

Using ArcScripts

I use ArcGIS 10 I want to use an arcscript to compute an index of ruggedness for each cell of my map. For this purpose, I found, Evan's TRI.aml script here: http://arcscripts.esri.com/details.asp?...
3
votes
1answer
171 views

ArcPy delete terrain: cannot be deleted

I can't get my ArcPy script to delete a terrain. If it exists, it should be deleted. However it throws an ERROR 000317: {path} cannot be deleted My script is a lot longer than this, but this is ...
3
votes
1answer
527 views

Converting contour lines to terrain dataset?

I have downloaded free DEM from the NET and I generated a contour line with 10 meter for interval. So, I just want to convert the contour lines to LAS point file to create a new terrain dataset. Is ...
3
votes
2answers
2k views

Is it possible to give 2d contours a Z-height from their attribute table in QGIS? (Or ArcGIS?)

I have a contour data file downloaded from UK Ordnance Survey, which gives 2d contours of an area in gml format (also supplied in .shp format) with the heights of each contour attached to the ...
3
votes
2answers
549 views

Which Statistical Test to use?

I aim to determine whether there is a correlation between terrain variables (elevation, aspect and slope) and structural information acquired in forest survey. I have used ArcMap's extract multi ...
3
votes
1answer
1k views

Google Earth import terrain

Today, Google Earth allows you to import images to overlay on existing terrain. Is it possible to import custom terrain to replace default terrain in Google Earth? There doesn't appear to be any ...
3
votes
1answer
161 views

Looking for more realistic 3D terrain renderer than ESRI Arcscene

I am looking for simple suggestions of software packages that go beyond what ESRI ArcScene can offer. I want to create 3D terrain visualisations, particularly of orthophotos draped over high quality ...
3
votes
2answers
100 views

Cesium terrain tiles too high by roughly 30m

I'm using the NED 1/3 arc second data set to generate tiles to zoom level 15 for Cape Canaveral in Florida, and finding that the terrain looks accurate in appearance, but the elevation is too high by ...
3
votes
1answer
994 views

Usage of Cesium Geoserver Terrain Provider Plugin for a single tile of SRTM90 data

I'm attempting to use Cesium Geoserver Terrain Provider Plugin for terrain visualization. I downloaded one tile from http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp address such as 42_05 region. I ...
3
votes
1answer
451 views

Hydro-Enforced/surface constraint DEM Creation using GRASS/QGIS

I am wondering if there is a way to create a hydro-breakline enforced DEM by means of any open source solution? I am able to create a DEM from Lidar data using GRASS, but would like to enforce some ...
3
votes
1answer
203 views

How to export data from saga or tas into excel?

I want to derive terrain attributes from DEM with saga and whiteBox GAT (SAT). I have problem in exporting data into excel. would you help me?
3
votes
2answers
397 views

Hillshade for 30m NED at continental scale

I'm new to terrain analysis. I have a 30m NED DEM (.tif) for the conterminous US. I would like to generate a nice looking hillshade for the US, but it looks bad - as in pixelated and rough (See image)....
3
votes
0answers
49 views

Using dynamic terrain in cesium?

I've been looking into tools for displaying dynamic terrain (x,y,z(t)) via the browser and I just recently came across cesium.js which looks like a wonderful tool at first glance. Many of the demos ...
3
votes
0answers
749 views

Creating one DEM from multiple ASC files

I am struggling with this several days and now its time to ask how to do it in QGIS. I have very detailed 27 ASC grid files with overall size of 9 GB created from 1m contours of large area (600 m2). ...
3
votes
1answer
180 views

Can 2D polygon be used as hard breakline for terrain in ArcGIS Desktop?

I've been working with TINs for years and have only ever been satisfied when using 3D polylines for breaklines. I am currently transitioning to using terrains and after reading the documentation in ...
2
votes
2answers
55 views

How can I extract flat surfaces from a DEM with GRASS GIS?

How can I use GRASS GIS to get the flat surfaces in this DEM into polygons? The picture is used to show the clearly defined flat surfaces.
2
votes
1answer
7k views

Can Compound Topographic Index (CTI) / Topographic Wetness Index (TWI) produce negative values?

I am calculating Topographic Wetness Index for a study area using SRTM DEM (90 and 30m). I've seen several versions of TWI (CTI). I have been using: TWI = ln(As +1 / tanB) where As = ...
2
votes
2answers
411 views

Terrain Accessibility map using GIS (ArcGIS or QGIS)

I need to make an accessibility map showing the walking distance based on the terrain and availability of road networks, could anyone point me in the right direction where i could learn to do so. ...
2
votes
1answer
54 views

Remove terrainProvider from scene (ol3-cesium)

I'm using ol3-cesium for creating 3D globe and cesium terrain provider to show terrain data on globe its working fine. this.scene.terrainProvider = new Cesium.CesiumTerrainProvider({ url : "http://" ...
2
votes
2answers
74 views

Return Image from WMS service

I asked this question, and I realize that I am going in the wrong direction. So, I would like to do this : var geom = new THREE.Geometry(); // push vertices here var some_material = new THREE....
2
votes
1answer
689 views

Cause of ERROR 000539: Error running expression?

The following errors in ArcMap are preventing me from moving forward: 1) In Raster Calculator using "Aspect": "%DEM_Aspect%" <= 90 or "%DEM_Aspect%" >= 270 ERROR 000539: Error running ...
2
votes
1answer
150 views

What is a “CFG” application in GIS terminology probably?

I come across a 2008 tech presentation PDF on "GIS-Enabled Modeling and Simulation (GEMS) presented by ESRI (i think for the US Army). On one of the page titled "Challenges to be overcomed", there is ...