A spatial operation in which two or more maps or layers registered to a common coordinate system are superimposed, either digitally or on a transparent material, for the purpose of showing the relationships between features that occupy the same geographic space.

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2
votes
1answer
61 views

Calculating total area overlapping specific raster DEM color interval whose boundaries are confined by another vector?

I know this sounds quite difficult, but maybe it isn't for you or at least it shouldn't if I explain it correctly. (I'm using QGIS 2.14) I'd like to know to calculate total area overlapping a ...
0
votes
0answers
31 views

DotSpatial Opposite of Featureset.Intersection

DotSpatial 1.8: I have some code to give me the intersection of my trip polyline and where it crosses key polygon regions. That works well: Dim fsResults As IFeatureSet = ...
0
votes
1answer
21 views

Tile server overlay in Google Earth?

I have recently become aware of a number of tile-server map sources and I would like to use these as overlays in Google Earth. Is there a way to do this directly that does not involve pre-downloading ...
0
votes
1answer
26 views

Leaflet Basemap and Overlay Display

When running this why does the open street layer not show up as the base layer by default? and why does the precipitation layer come up as already checked to display? None of the other overlays ...
1
vote
1answer
32 views

How to delete overlay within the same feature class?

So, the following scenario: I have plenty of polygons that are within another polygon, all in the same feature class. All of the polygons (the one overlaping the other ones as well as the ones being ...
2
votes
1answer
20 views

How to display data at diffrent depths in ArcScene

I am looking for a way to display data at different depths in ArcScene. I have a bathymetry layer which displays fine, and I want to overlay oil platforms in 3D over the bathymetry to show where ...
8
votes
6answers
9k views

how to overlay a polygon over SpatialPointsDataFrame and preserving the SPDF data?

I have a SpatialPointsDataFrame with some additional data. I would like to extract those points inside a polygon and at the same time, preserve SPDF object and its corresponding data. So far I've ...
0
votes
1answer
170 views

How do I view ovl files on Geogrid or Top50 then convert the data to shapefiles?

I have some .ovl files which can only opened on Geogrid or Top50 viewer which shows me where everything is. How do I take these ovl files and convert the properties to Shapefiles to be used on ArcMap ...
1
vote
1answer
217 views

CartoDB - Method to show/hide layers for hatching overlap for > 4 layers?

Our goal is to show/hide individual hatched maps. Unfortunately we have more than the 4 max layers allowed in a viz. We successfully made and example where we show/hide the 4 layers in a viz: ...
2
votes
1answer
438 views

OpenLayers3: How to show a KML layer with the export to png Button

so... I have this script: <script> //Script1: Script de criação do mapa. var map = new ol.Map({ layers: [ new ol.layer.Tile({ ...
1
vote
1answer
77 views

How to add OpenSeaMap tiles as an overlay on top of osm base map with Leaflet?

After generating the OpenSeaMap tiles, I tried to add them as an overlay upon the openstreet basemap. The idea is after generating the OpenSeaMap tiles to serve them as "static" tiles to the client, ...
1
vote
1answer
19 views

In ArcGIS Modelbuilder: Mean value of different polygons within a buffered zone, weighted by area percentage

I am creating a model in ArcGIS model builder (10.2). I have buffered zones (polygons) and within these zones there are different soil types (polygons; Shapefile feature class). I have assigned values ...
3
votes
1answer
51 views

Polygon made by colour difference

I need to analyze differences (historical) in coverage of some species (seagrass Posidonia). Although its a marine species, subject area is very shallow and even from common satellite and aerial ...
0
votes
0answers
15 views

Overlay tools failure in ArcGIS 9.3 [duplicate]

I consistently get various error messages almost everytime I try to use an overlay tool (e.g. union, intersect, clip, spatial join) or in one case with spatial join I got none-sense results. Some ...
0
votes
1answer
324 views

Is Tile same as Layer? [closed]

Is there difference between a tile server or a layer server? Can I load tile in ArcGIS control in WPF from some other source? Can I host my own layer server? Or is there any such thing as layer ...
2
votes
1answer
414 views

Loading texts with shapefile in ArcMap

I am currently trying to load different shapefiles in ArcObjects programmatically. Currently I can load lines, polylines, polygons and ellipses (even though that's just a fancy polygon as far as ...
2
votes
1answer
52 views

Aggregating up spatial information

At present I have a dataset which is broken down by Electoral Divisions (circa 3,500). However, due to issues with some of my variables I need to choose a larger spatial unit - Local Electoral Area ...
4
votes
1answer
25 views

Defining city name by using KMZ files

We have KMZ files of different satellite images. We want to check which cities these satellite images belong to. Is there a way to do it automaticly? Like a tool in ArcGIS or QGIS or whatever?
1
vote
1answer
22 views

v.overlay in GRASS

As I understand, v.overlay module can be used for polygons overlapping processes. Polygon clipping, union processes can be done. There are many algorithms for these operations. Which algorithm is ...
1
vote
0answers
22 views

google earth - viewing KML file in world map

I"m using google earth and a KML file that I have generated. I would like to display all the KML points in a world map. Google maps online does it but the print is poor. Need a 300 dpi print which ...
2
votes
1answer
45 views

PostGIS function ST_SymDifference between two segment groups produces unexpected results

I try to calculate the symmetric difference for a set of segment groups A and B with precision of 1E-5 (ST_SnapedToGrid(geom,1E-5). I've formulated the an ideal test case for a H based shape segment ...
1
vote
0answers
37 views

Georeferenced Image Overlay and export to new image

I have two Geotiffs (one satellite image, one clipped image). I want to put the clipped image over the satellite image, because it shows flow velocity from this shown glacier (see image below). I ...
1
vote
1answer
20 views

Counting points on a line or polygon using join: number of points are calculated incorrectly [closed]

I am attempting to count the number of stream crossings within approx. 100m segments of a trail. I used this article to get quite close with join: ...
0
votes
0answers
26 views

Can I overlay a CartoDB visualisation on Bing Maps base?

If I am using Bing Maps as my base map, can i overlay a CartoDB visualisation (that I created earlier) on top of it? If so how do I go about doing that? The example on the cartodb site only refers to ...
1
vote
0answers
57 views

Leaflet.js setBounds, scaling

I'm using leaflet.js to create a map of Scotland, with two insets for the Orkney and Shetland groups of islands. This is as far as I've got. I wish to guarantte that no matter what size the overall ...
5
votes
2answers
100 views

TileStache Vector Tiles Overlay problem

I am using TileStache to serve my own vector tiles using a postgis datasource. First I re-projected the shapefiles I had using ArcMap ( reprojected to Web Mercator (Auxilary Sphere)) and loaded them ...
1
vote
1answer
361 views

how can I make “weighted sum overlay analysis” in QGIS? Ordered Weighted Averaging manual may be useful

I have weighted raster data converted from polygons with different categories. I have ArcGIS with 3D Analyst extension, unfortunately do not have Spatial Analyst, and I would like to use QGIS to make ...
1
vote
1answer
607 views

Selecting raster data by location: for raster and feature class data

I have rasters covering certain spots in my environment, I'm looking for a way to extract the values which occur at locations which are defined by a selection of feature layers. I've tried with the ...
2
votes
4answers
1k views

Produce a list of polygons that a line crosses

I have a polyline feature class and a polygon feature class. What I want to do is add a field to the lines that lists all polygons that touch the line. This is effectively performing a ...
0
votes
1answer
60 views

compare three rasters and three conditions with overlay in r

I'm trying to run an overlay function with rasters where I want to meet all of 3 different conditions at each cell and produce a single raster as output. Running ifelse with the & operator ...
4
votes
1answer
385 views

Check/uncheck overlays in groupedlayercontrol.js

In a Leaflet-based app I have create several overlays, grouped with leaflet.groupedlayercontrol.js, as shown in this image: Everything works well, but I need to uncheck certain layers, allowing the ...
0
votes
1answer
74 views

Is it possible to join two different data sets in QGIS?

I have one data set which contains all federal states of Germany. The other dataset is about the population density in every km² in the EU. My goal is now to join these two Datasets so I can answer ...
1
vote
3answers
882 views

“Identity” overlay in QGIS?

I have two polygon layers I'd like to overlay using QGIS or another open source tool. What I want as output is a polygon layer with the extent of one polygon, but with each polygon in that layer ...
-3
votes
1answer
64 views

Same coordinate system - shapefiles don't overlap [duplicate]

I have two shapefiles and two rasters (dem), and while I put them in the same coordinate system (Greek grid), it seems that they don't overlap. But one is the boundaries of a county, and another the ...
4
votes
2answers
377 views

Determining area of county land mass without water features using ArcGIS Desktop?

Here are the layers that I have: State / Province polygon file (With Area Field) County / Ward polygon (with no area field), but all the polygons are within the state boundaries Water ways for the ...
1
vote
0answers
35 views

Can MapboxGL use nearest neighbour interpolation for overlay image? [closed]

In HTML+CSS version of mapbox/leaflet I can set image-rendering option for .leaflet-image-layer with CSS to choose interpolation method. How can I make this in GL renderer?
1
vote
1answer
200 views

Calculating coverage of vector polygon over other polygons?

I have a shapefile file that contains a LiDAR footprint and I'm trying to figure out how much a county is covered by the LiDAR footprint. Two separate shapefiles. The attribute table for the county ...
4
votes
1answer
412 views

How to get a GML overlay on Google Maps?

Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me. A bit of ...
2
votes
0answers
250 views

GRASS v.overlay.or Error when trying to split a polygon with a line

I am using the Grass plugin in QGIS for Windows (1.8.0). I am trying to split a polygon with a line feature. I am using the v.overlay.or function within the QGIS Grass plugin. I have the line layer ...
1
vote
0answers
33 views

Polygon overlay, calculating changes, in QGIS?

I'm trying to create a relationship file between two vintages of census tracts. (in this case, 2010 and 2013.) Reason being to load ACS (American Community Survey) census data and use weighted means ...
0
votes
1answer
60 views

How to overlap a base map with a png map (format .pgn) on QGIS-Pisa?

How can I overlap a relief base map taken from maps-for-free.com and this png-formated map so that I can get a resulting map with relief of the 1st map and boundaries of the 2nd map ?? I'm a ...
1
vote
1answer
46 views

Determine the range of values in one raster associated with certain values in another raster

I have two rasters, one with thematic data, and the other with continuous data (floats). I am trying to calculate/determine the the range of float values associated with the different classes in my ...
1
vote
1answer
32 views

How can I remove feature selection from my layeroverlay in mapguide API?

I can add feature to my layeroverlay on mapguide API, but I don't know how to remove it. Can you help me find a method to remove a feature from a selection ? This is how i add features to my layer : ...
2
votes
2answers
65 views

Selection on Overlapping Polygons

I have converted a CAD file to GIS format using GIS (from .dgn to .shp)... In one layer I have polygons in which a smaller one is on top of the larger polygon. I can see both polygons however when I ...
1
vote
2answers
52 views

How to overlay subset of one data set onto another

I have two data sets: one for Thurston County, Washington and one for all of Washington state. I created a map of hydrology features in Thurston County, and now I want to take the data from the ...
3
votes
1answer
65 views

Get tile layer intensity at given zoom and longitude/latitude (Leaflet)

I can display a tile layer as an overlay in Leaflet via an url of the form path/to/my/tile/layer/{z}/{x}/{y}.png : my_overlay = L.tileLayer('http://path/to/my/tile/layer/{z}/{x}/{y}.png', { maxZoom: ...
0
votes
1answer
96 views

Closer for measureToolTip, openLayers 3

I want to add for my map measure tools. I added distance for line and square for polygon. Also i added erase for drawed element, but i can't to clear measureTooltip. First I try do it with ...
1
vote
1answer
14 views

Redefined Topo and Shape file still wont overlay

I am trying to overlay a topographic map that is a raster and a road shape file. The road shape file was originally not defined. I defined the projection to NAD_1983_2011_Contiguous_USA_Albers and I ...
0
votes
1answer
119 views

Making a KML layer “always on”

Is there a KML tag or specification by which you can force a given layer (specifically, a screen overlay) to be "always on", in that there is no way for the user viewing the file to make that layer ...
2
votes
1answer
31 views

How to show overlay in layout legend [closed]

I am displaying three different layers on a map, essentially three separate habitat types. Each have their own colour. In cases, 2 or 3 of the layers overlap in part (essentially showing where ...