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
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1answer
40 views

How do I edit multiple features at one time?

In my case, there are about 30 overlaid features. How do I select all and edit them at one time? I want to reshape the features, mainly using the node tool to reshape a straight line into a (fake) ...
2
votes
1answer
190 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
1answer
64 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
vote
1answer
37 views

Projection bug between overlay and base layers

I am making a WebGIS application for a course and I am trying to integrate some nice base layers like OMS, Stamen, and Bing Maps with my overlay layers that are for Bolivia from a Bolivian map ...
1
vote
1answer
35 views

Weighted Overlay Decimal Values for Evaluation Scale

I would like to do a weighted overlay of different raster datasets. I would like my evaluation scale to be from 1 to 10 with 0.1 as the incremental value. This way for example a criteria could have ...
1
vote
1answer
85 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
82 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: ...
1
vote
1answer
56 views

2 Legends in Leaflet

In Leaflet I want to add a legend when I turn on an overlay, then when I turn off that overlay I want the legend to disappear and when I turn on a second overlay I want a second legend to appear. I ...
1
vote
1answer
76 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 ...
0
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1answer
39 views

Copying the visual shapes from another layer to the current one, while keeping the current layers' database

There are 2 layers that have similar shapes but small differences. I want to keep the shape of layer 1 while having the data of layer 2, which includes more data and it will be animated using ...
0
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1answer
28 views

Growing error from west to east when overlaying raster and shape

I am using a shape of Austria from gadm.org which I want to overlay with a netCDF file in R. As the netCDF has projected coordinates in EPSG:31287, I have reprojected the shape using FWtools and the ...
0
votes
1answer
115 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({ ...
0
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1answer
24 views

Is there a way to overlay a remote kmz file in google maps

I have a kmz file and want to overlay it on google maps. What I'm searching for is sth. like: https://www.google.de/maps?kmz=server/tour.kmz I've already checked the query params for google maps, but ...
0
votes
1answer
96 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 ...
0
votes
1answer
109 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
votes
1answer
52 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
votes
0answers
130 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 ...
2
votes
0answers
42 views

How I can create a raster and have the same overlay as another raster in QGIS 2.4?

I have made a graphical model in QGIS 2.4. I have to create a raster equation to rasterize a polygon shapefile. I want to rasterize my shapefile and I want to ensure that this new raster will ...
2
votes
0answers
452 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 ...
1
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0answers
32 views

how to use arcGIS to calculate the Conversion Probability certain land use to other land use?

I am doing dissertation about [predicting future urban expansion for Shannon River Basin In Ireland using Cellular Automata model and arcGIS] so at this stage I would like to calculation the ...
1
vote
0answers
15 views

Shaded KML overlays on OSM tiles in QGIS?

This seems simple - but the solution is escaping me. I have a series of dynamically generated KML files describing simple, shaded polygons, with each polygon having a slightly different (externally ...
1
vote
0answers
22 views

Risk Maps - Spatial Analysis

I have created a basic mining subsidence likelihood map which contains the variables of depth and distance from lineament using the weighted overlay tool. From these results I would like to create a ...
1
vote
0answers
529 views

How to overlay a flat image onto google maps with two points of reference?

The Android API allows for images to be superimposed onto a map. To do so, the developer specifies a set of lat/long coordinates for an "anchor point" within the image, the width (or height) of the ...
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0answers
158 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 = ...
1
vote
0answers
69 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
198 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 ...
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0answers
57 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 ...
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vote
0answers
179 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
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0answers
378 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
664 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
0
votes
0answers
24 views

Using R to find attributes of spatial neighbors, especially with big spatial polygon data frames

If it's not too much, I have a specific question that leads to a more general one: I'd love thoughts on both if it's possible. First, the specific: I have an analysis involving census blocks and ...
0
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0answers
12 views

Problems in overlaying NWS flood maps on Google maps

Hope you are doing good. My team is trying to overlay NWS flood maps on to Google maps. The steps we are following are as given below. We downloaded the flood maps from NWS in the raster format ...
0
votes
0answers
48 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 ...
0
votes
0answers
20 views

Adding an overlay in specific index

I'm trying to add my overlays in a specific order to the map. therefore I: var overlays = map.getOverlays(); overlays.insertAt(0, overlay1); overlays.insertAt(1, overlay2); overlays.insertAt(1, ...
0
votes
0answers
23 views

Overlay sales data on maps

We have a project to build a sales reporting tool that will show sales and other data from various field outlets on a map. The idea is to give our decision makers a geospatial zoom-in of our ...
0
votes
0answers
33 views

Weighted Overlay not showing all values

In a ModelBuilder, my final step is to add a weighted overlay at the end. I have 4 reclassified layers as the input, all equally weighted and all contains values 1-10. However, when I run the Weighted ...
0
votes
0answers
33 views

ERROR 6: The PNG driver does not support update access to existing datasets

I was trying to overlay a shapefile to some raster images from a directory using gdal_rasterize. But then encountered this error ERROR 6: The PNG driver does not support update access to existing ...
0
votes
0answers
25 views

QGIS multiply(add) two raster but divide(deduct) another raster

I am making a parking analysis in one town. I need to obatin the zones where the parking of car is harder because there is less places to park and higher demand of cars.I have three rasters. First ...
0
votes
0answers
79 views

Displaying Google Maps with GroundOverlay KML and Openlayers with vector KML

I've got several different KMLs I need to display. Some have vector elements, others just have ground overlay elements as pngs. I need to have them both on one map. Google does that great, except ...
0
votes
0answers
59 views

Why does a (relatively) small .CSV file break the Mapnik CSV plugin?

I have an app showing a map of N. America, and I want to let users toggle a layer displaying airports. The map needs to be available without an Internet connection, so I'm hosting the tiles and ...
0
votes
0answers
107 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 ...
0
votes
0answers
102 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
votes
0answers
197 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 ...
0
votes
0answers
35 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
votes
0answers
229 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 ...
0
votes
0answers
92 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 ...