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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2answers
290 views

Transforming a google maps overlay to fit a Ordnance Survey projection

I am currently in the process of creating a map with some administrative boundaries on it. The base map I am using is an ordnance survey map 1:10000. I downloaded an administrative border as a .kml ...
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2answers
372 views

OpenLayers: Strange Tiling Issue (Checkered, white and grey) when panning around map

So this strange tiling issue is only occuring when moving around the map. Some things to note: 1) You can see the markers, airplane icon, and flight paths. These are all overlays, where the actual ...
5
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1answer
429 views

Generate tiles for google maps overlays

I am trying to show some information on Google Maps which would be in the form of translucent circle overlays. The problem is that some circles overlap, which results in increased opacity and blending ...
2
votes
1answer
31 views

strange banding in output raster after weighted overlay

I am trying to conduct a weighted overlay. I have two rasters, one is a continuous slope raster that I reclassified to have 6 classes (8bit signed integer), and one is an elevation raster that I also ...
1
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1answer
68 views

Stamp out and transfer values from one overlayed vector layer to another

I have a vector layer with administrative boundaries and another vector layer with postal code boundaries, which are more precise/smaller entities/objects. I now want to transmit the values of one ...
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1answer
43 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 ...
0
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1answer
135 views

I can not override my WMS layer in Google Maps as a base

I can not override my WMS layer in Google Maps as a base: I have a WMS layer in geoserver am using openlayers to show them. Calling only works WMS layer:   see my code, I am using using the bounds ...
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1answer
40 views

Calculate best area with overlaying multiple layers buffer shapes

I am using QGis and I have a set of 20 layers with buffers. I'm interested in where they overlap most and I want to create a single layer that shows which are the places where they overlap most and ...
2
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0answers
342 views

Creating a sidewalk map for a walkability survey

If I wanted to do my own walkability survey of my city, what tools could I use? I have map data from OpenStreetMap, but I have to consider that streets have two sides (which aren't always accessible ...
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0answers
67 views

Problem with polygon overlay in raster stats using gdal

I am using the raster_stats module in python to calculate the mean carbon value for different sets of polygons. Here is the code that I am using: africa_sat = ...
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0answers
33 views

Calculating Percent Overlap Between Distribution Maps

Hello there, I am currently trying to calculate the percent overlap (basically the total amount of overlap where these two species come into contact) between Lithobates catesbeiana (first image) ...
1
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0answers
71 views

QGIS plug-in equivalent of ArcGIS's Spatial Analyst Tools -> Overlay/ Weighted Overlay

Specifically I have 12 .bil raster files that show monthly global mean minimum temperature. I file for each month. I want to combine these to create an ANNUAL global mean minimum temperature. In Arc I ...
1
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0answers
119 views

Replace google map MARKER with HTML element

I want to add a custom HTML element (that can become transparent dynamically) instead of a marker. Basically my html object would be a cirle (or rounded pin) with a picture of users in the middle. ...
1
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0answers
48 views

How to maintain polygon boundary location during overlay in ArcGIS

I am working with ArcGIS Desktop 10.1 (Advanced license). I am trying to overlay two polygon layers (buildings and landuse) via an Update overlay such that all building polygons are retained and the ...
1
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0answers
100 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
289 views

Raster Over Layer in Leaflet from GeoServer

I want to add a raster over layer onto the base layer and the raster layer is published by a Geoserver WMS. I set the raster layer's geographic coordinate system as the same as the cloudmate tiles. ...
1
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0answers
431 views

Zipcode overlay on OSM

I have to display an overlay with different colors depending on the zipcode in Europe. Can I get this information from OSM shapefile ? If yes, how exaclty ? Is there a tutorial somewhere ? Thanks
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0answers
22 views

How to hide overlays in Leaflet layerControl if geojson var not found?

i would like to perform a specific task: i have a set of geojson layers, loading features from local files. i have the layercontrol on the map showing available layers to show/hide now, regarding ...
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0answers
19 views

Overlaying Line (Vector) Layer on Raster Zones?

I will make my best attempt to clearly explain my problem. I am using ArcGIS 10 I have a raster layer with 3 values that make up zones. For the purpose of this example, lets say these zones are ...
0
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0answers
12 views

Is the geoxml3 javascript API compatible with the mapstraction API?

I am getting ready to revamp a google maps application and I was considering utilizing mapstraction. I am currently using all google maps js, with a kml layer overlay, but obviously by using the ...
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0answers
19 views

Spatio-temporal Overlay

I have a SpatialPointsDataFrame that lists satellite-detected fires (firesutm), including location and date. I also have a SpatialPolygonsDataFrame with county boundaries (countyutm). I would like ...
0
votes
0answers
66 views

QGis, how to overlay and correctly position and scale a KML and image onto a Google base map

Being totally new to the entire GIS subject I managed to install and get runnning QGis (2.2.0 on Mac) properly, get my Google Maps showing (I set the the CRS to WPSG:3857) and I also got my KML file ...
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0answers
27 views

Overlapping of two layers in MySQL spacial extensions

I have been into GIS for almost a week now. Right now, I am learning MySQL spacial extensions. I have a question regarding the functions MySQL provides: I have a table that consists of LineString, ...
0
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0answers
48 views

Removing multiple categories from GRASS vector feature

Pardon my lingo if this is not entirely correct - I am a software developer, not a GIS person. We're working a project that uses v.overlay to merge a map of slopes with a map of soil tests to produce ...
0
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0answers
122 views

How to import AutoCAD .dwg files as overlay on map in Drupal (using OpenLayers)

I am using OpenLayers on my Drupal site. The request is to import AutoCAD .dwg files as an overlay to maps on the site. Is this possible and how? I found the OpenLayers Editor for Drupal, am I on the ...
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0answers
45 views

Not a valid data source of kml created from image overlay by Google Earth

I did image overlay in Google Earth and saved it as kml file. But it was showing me that it is not a valid data source when add it as vector(kml) in Qgis 1.8.0. Any solutions? Thanks!
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0answers
20 views

No values in overlay tab, only in diagram tab

I have basically the same issue like in this post. I joined a table to a .shp with the intention to display those values (integers) as a column overlay. Producing pie charts (Diagram tab) works fine, ...
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0answers
101 views

openlayers can't show an image layer in the right place starting from a center point

I have to draw an image over the map as an overlay. The image is, for example, 400x400 pixels and represents an area of 400x400 kilometers. I'm using an Image Layer to do this. I have, as reference to ...
0
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0answers
108 views

Openlayers: Disable entire map being dragged and remove white space in viewport

I am trying to make a map with overlay such that when at zoom level 0, the white space in the map view port does not show up and the map is not draggable. At zoom level zero i would like to have the ...
0
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0answers
49 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 ...