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.
1
vote
0answers
29 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 ...
3
votes
2answers
75 views
How to calculate the shared area between a raster and a shape file in ArcGIS 10?
I have a raster file with 5 classifications developed from habitat modelling algorithms. I'd like to know how much of 2 classes of the raster is covered by the network of protected areas (Shape file). ...
1
vote
2answers
51 views
Calc vs. Overlay for speeding up band math in R 'raster' package?
Regarding yesterday's question about how to speed up band math in the R 'raster' package, would it be the same to use overlay to calculate NDVI instead of calc? If that's not the case, what's the ...
1
vote
1answer
106 views
ArcMap 10.1 Spatial Join: 'Contains' and 'Within' question
I have two polygon datasets: electoral districts and postal code areas. I'm performing a spatial join to see which postal code areas are completely within a district (the area can touch the borders, ...
3
votes
2answers
145 views
Overlay Vector Layer on Raster Layer
How can I overlay a Vector Layer on a Raster Layer and assign NoData Values on the Raster where the Vector Layer does not cover the Raster Layer?
(preferable with ArcGIS)
3
votes
1answer
103 views
Find which grid cells contain a point
I have a dataframe with x,y coordinates. I've sampled 10 x,y coordinates from my dataframe:
y <-c(24.637032,21.569813,21.687,19.677183,24.72438,21.433136,24.637032,22.21065,21.443762,25.273882)
x ...
1
vote
1answer
38 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 ...
5
votes
1answer
120 views
What tool do I need to have satellite background images to draw features of a postgis database?
What tool do I need to have satellite background images to draw features of a postgis database?
I looked about Geomajas but seems very complex for what I'm trying to do.
I have osm data imported in ...
4
votes
1answer
211 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 ...
4
votes
2answers
427 views
Display Georeferenced Images on Android
I'm looking for an Android application (best would be Open Source), that can display georeferenced images on top of a map (Google, OSM, ...).
By Georeferenced I mean that the images four corners are ...
1
vote
0answers
152 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. ...
0
votes
1answer
154 views
In leaflet does the addControl automatically handle events via the leaflet API?
I need to add additional overlay layers to be controlled by the controls within the leaflet map boundaries, but the code utilizes a leaflet-custom.js file. I am assuming it handles the event and ...
2
votes
1answer
76 views
How can I enable panning using Openlayers and a vector overlay with controls?
I am creating a map using the following code:
map = new OpenLayers.Map({
div: "map"
});
Then I load in a geojson polygon layer and add two controls
var highlightCtrl = new ...
4
votes
1answer
267 views
Shapefile vs Arrays of coordinates to build Google Maps overlay?
I am very new to GIS, and my task is to overlay about 100 polygons on a map. I'm using Google Maps Javascript API v3.
I think I can define all my polygons as sets of lat/long coordinates in my ...
2
votes
3answers
2k views
Can OpenStreetMap be used as a WMS service in MapServer?
I want to produce a png image that uses OpenStreetMap data and has a vector overlaid on the base data. I am able to produce the vector overlay from within Mapserver, but I have difficulty ...
2
votes
1answer
135 views
Overlay analysis of topographic data
I have a topographic map with Buildings, Roads, Hydro and land use as the prominent layers in polygon format. Also i have newly collected Building polygons of the same area in shape file format. Now i ...
0
votes
1answer
145 views
Does a polygon in a layer intersect with another polygon in the same layer [closed]
I am a CS major with little experience in GIS. I am working on vector polygon overlay. Looking at GML and shapefile data, I realized that a map is made up of a large number of polygons. Does a polygon ...
3
votes
1answer
464 views
UK region overlay on map
I'm hoping to overlay UK regions (East Midlands, Wales, London etc) on a Google Map. Ideally the regions could be coloured, opaque and have some form of label. There is no hover / interaction ...
0
votes
1answer
84 views
overlay a county shapefiles for 2 different years [duplicate]
Possible Duplicate:
overlay county shapefiles for 2 different years
2 down vote favorite
I have county-level shapefile for South Caroline in 1880 and one for 1940. I would like to overlay ...
3
votes
2answers
157 views
calculate coastline at risk
I have an idea of what I want to do but I don't know yet what tools will bring me there.
I have administrative boundaries in one layer and coastline in another layer. The coastline is categorized in ...
2
votes
1answer
195 views
Technique using GDAL to overlay / fit one PNG map to directly overlay on another?
I have one .PNG basemap with known North edge of Latitude = 52.48, a South edge of Latitude = 21.94, an east edge of Longitude = -61.87 and a west edge of Longitude = -129.37.
And I have another PNG ...
4
votes
3answers
259 views
Can I have Points, Lines and Polygon features in one QGIS layer?
I have a situation where planning is done on a "base map" consisting of rivers, contours, roads etc. There is a need to create a "overlay(s)" over the "base map" consisting of drawings, that could be ...
1
vote
1answer
105 views
Summarize polygon area using another polygon
I have a shapefile representing public/private lands in Montana. This is a multipart shapefile where I've simplified attributes so that #1==private and #0==public.
Next I have a shapefile of ...
0
votes
1answer
2k views
How do I overlay a KML on leaflet 0.4.4
I am using Leaflet 0.4.4,
I have a KML I would like to overlay on the map, how do I go about doing this?
Edit: I am already aware of https://github.com/CloudMade/Leaflet/issues/14, which directs ...
1
vote
0answers
226 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
5
votes
4answers
1k views
explode overlapping polygons to new non-overlapping features
Given multiple polygons that overlap in multiple ways, I would like to export from this feature all polygons that don't overlap with others iteratively. The product would be a number of features with ...
3
votes
2answers
841 views
Load layers only when zoom level is reached
I'm trying to load different layers based on the user zoom level with OpenLayers. I've seen some similar questions in here, but they load the layer and then hide/show it based on the zoom level.
I ...
1
vote
2answers
760 views
OpenLayers WMS disappears when including OpenStreetMap
Setup:
ArcSDE 9.3.2
Oracle 11g
GeoServer 2.1.4
OpenLayers (latest build)
OpenStreetMap
InternetExplorer 7.0/ Google Chrome
EDIT: I have updated information just below the screen shots
...
6
votes
1answer
280 views
overlay county shapefiles for 2 different years
I have county-level shapefile for South Caroline in 1880 and one for 1940. I would like to overlay these two files so that they do the union and indicate the percentage of the land in 1880 that went ...
1
vote
1answer
154 views
How can I move diagrams?
Is there a way to locate diagrams and move them wherever you want in QGIS 1.7.4/ 1.8.0?
I created a pie chart under the tab "diagram". I can mark those diagrams with a green box and move them via the ...
1
vote
1answer
256 views
Can't display overlay
I am trying to add a WMS radar overlay to my map but it won't seem to gather it.
noaaRdr = new OpenLayers.Layer.WMS("Latest Radar", "http://nowcoast.noaa.gov/wms/com.esri.wms.Esrimap/obs?", {
...
0
votes
0answers
94 views
Overlay shapefile data on the Map using Esri arcgis Javascript Api 3.0
Is there any way to overlay the shapefile data containing in the subfolder of the solution on to the map control of ESRI's Arcgis javascript api 3.0.Thank you in advance.
0
votes
0answers
129 views
Overlay polygon layer A over Polygon layer B
If I overlay postal codes (Zip Codes in US) over census tracts where postal codes are usually larger than census tracts, how can I get a table of what percentage of the area of the census tracts are ...
2
votes
1answer
220 views
Area overlay of census on Zip Code
I have census block data polygons. I want to overlay them over Zip Codes (larger polygons) in order to estimate the population in the Zip Codes. Or overlay buffers around toxic waste sites over census ...
1
vote
2answers
246 views
count features in polygon shapefile A that fall within each feature of polygon shapefile B
I have two polygon shapefiles, each of which contain multiple (possibly overlapping) polygons.
Is there some way, using GRASS, to calculate the number of polygons belonging to shapefile A that fall ...
3
votes
1answer
640 views
Why does my WMS layer overlap the Google Maps v3 logo?
I'm using Google Maps v3 as a base layer and on top of that I create an overlay pointing to my WMS (streets and avenues).
A few months ago all works fine, my WMS layer was not overlapping the Google ...
1
vote
1answer
286 views
Merge two maps with OR operation in GRASS
I have two vector maps. The two maps cover the same area but are split up into polygons differently (i.e. if you were to imagine one map placed above the other, the lines defining the polygons would ...
3
votes
2answers
442 views
Clip depth contour with spatial polygon
I need to somehow combine my Spatialpolygons with my depth contour, but not sure how do to so. Maybe create a SpatialPolygonsDataframe?
This is what I've done so far:
> class(subarea0) #This is ...
5
votes
1answer
632 views
How to rasterize SpatialPolygons in R?
I'm trying to extract the bathymetry values of my area of interest from a world bathymetry raster layer using the 'rasterize' function in the {sp} package.
*Edits: I found the 'extract' function ...
1
vote
2answers
318 views
QGIS layers no longer overlay when Enable 'on the fly' CRS transformation is on
My QGIS project has two layers - one retrieved from GADM (administrative boundaries of Guinea Bissau) and another one of the villages collected in the field using GPS Decimal Degrees - D.ddddd.
If I ...
2
votes
1answer
363 views
Select vectors overlapping a raster
I have a raster layer with travel times from a specified point in my city's downtown. What I'd like to do is select all of the census blocks that lie at least partially within 45 minutes of downtown ...
1
vote
1answer
645 views
Creating a Google Maps GroundOverlay with UTM NAD83 data
Edit4: The solution I posted from Jenner at VBforums was, obviously, in VB, and I used an online converter to port it to C#. Something was lost in translations, and that's why it was 10 miles off.
...
12
votes
3answers
5k views
Layers having the same coordinate system should overlap, but they don't. What's wrong?
I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I ...
4
votes
3answers
3k views
OpenLayers: Showing a WFS overlay on top of Google Maps
I have found similar questions asked previously, but I still fail to get a simple WFS point layer to work using OpenLayers and Google Maps. The original code I used was based on WFS polygon layers I ...
2
votes
2answers
1k views
How to overlay map layers (shp and csv) in R?
This is a crosspost from stackoverflow. I know very little about GIS software and am doing all my mapping in R. Apologies in advance if this is too basic question. Let's say I have two shapefiles from ...
0
votes
1answer
123 views
I am looking for a library or API to do vector overlay for two map layer (shapefiles or GML files)
I need to perform vector overlay operation on any two map layers as ArcGIS and Grass GIS performs. I am wondering is there any API or library ( in C, C++ or Java) so that I can use that third party ...
10
votes
1answer
375 views
Method to shade or overlay a raster map to reflect time of day and ambient light
I have a daytime raster of my study area.
I have 20+ counters in the study area that count "stuff" with a timestamp.
Using PyEphem I determined the type of ambient light for each collected data ...
3
votes
1answer
161 views
Calculating the time taken to complete the overlay display in map?
Currently, I am able to calculate the server response time by logging the difference of current date to initialize the map with the time when layers is added. But this gives me server response time. ...
2
votes
2answers
718 views
Image display/scaling in OpenLayers vs Google Maps
When I plot an image on OpenLayers, it looks like that image is stretched a little bit as compared to Google Maps. I was wondering if it is normal or there is something wrong with my code.
...
5
votes
1answer
2k views
Can image layer be rotated in OpenLayers?
While working on Ground Overlays, I noticed that it has a tag called <rotation>
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
...
