Questions tagged [overlay]

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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19
votes
1answer
9k views

equivalent of sp package's point in polygon / overing using sf

I am migrating code from sp package to the newer sf package. My previous code I had a polygon SpatialDataFrame (censimentoMap) and a SpatialPointDataFrame (indirizzi.sp) and I got the polygon cell id (...
17
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6answers
32k 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 ...
14
votes
1answer
3k 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 point. ...
11
votes
1answer
638 views

Creating a Radial Sector Overlay in QGIS

I need to create a sector grid radiating out from a point of interest. Here is an example that I laboriously put together by hand: I have found a couple of similar solutions in How to generate ...
10
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2answers
4k 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 ...
9
votes
2answers
23k 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 ...
9
votes
4answers
17k views

Reprojecting base layers in OpenLayers

I have vector/topo/image tiled maps for some places in North America which were published as ArcGIS Server REST service. These maps (A) are based in EPSG:26912 projection. Now I want to use these as ...
9
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1answer
3k views

How do I create an animation in google earth using png overlays with kml timestamps?

I have the following kml files, each with a different timestamp and png: <?xml version="1.0" encoding="UTF-8"?> <kml xmlns="http://www.opengis.net/kml/2.2" xmlns:gx="http://www.google.com/...
8
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2answers
870 views

Computing dominant area in polygon using ArcGIS Desktop?

First, I have a shapefile consisting of square grids and each grid has an ID. Second, I have a shapefile consisting of different zones (with IDs). A grid ID in the first shapefile can contain many ...
8
votes
1answer
8k views

OpenLayers WFS vector layer

I'm trying to add a vector layer with a WFS layer and it's not working. Can anyone point a solution? OpenLayers code: var wfs = new OpenLayers.Layer.Vector( "Stavros Features", ...
8
votes
1answer
5k views

How can I superimpose a geopandas dataframe on a raster plot?

I have a geopandas dataframe countries with country polygons, and a raster dataset raster (read with rasterio). I've already aligned the two as follows: countries = countries.to_crs(raster.crs.data) ...
8
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2answers
535 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 ...
8
votes
1answer
3k views

Generating grid shapefile in R?

I have the following shapefile of a 10x10 degree latitude/longitude grid that I created in QGIS. I can read it into R using the rgdal package. Grid<-readOGR(".","GridShapeFile") It has the ...
8
votes
1answer
5k views

Show markers only at certain zoom levels

I'm building a cycle touring map in leaflet.js, with subjective information overlaid as markers, along the lines of "this is a great road", "this town is quite nice" etc. To avoid information overload,...
8
votes
3answers
2k views

Create interactive map with no server

I have managed to build a great web mapping application using tiles created from GeoWebCache and a custom gridset, but I now need to add an overlay to the base maps. The only interactivity I need is a ...
8
votes
1answer
4k views

Draw route direction overlay on Google Maps or OpenLayers

I'd like to display the route direction generated from GraphServer on either Google Map or OpenLayers. The result I want is basically identical to how Google Map shows route directions, by ...
8
votes
2answers
1k 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 ...
7
votes
1answer
141 views

Changing blending of contour label to multiply

I would like to label my maps like these in QGIS (image created using Photoshop): Image of contour label being shown on the contour lines with with white halo and then the colored raster layer above ...
7
votes
1answer
2k views

Multiple overlay/intersection geoprocessing

Is there any GIS function which gives back the polygons of the intersections by storing the number of the overlapping surfaces to an attribute? Or do you have a script for this purpose? A sample pic ...
7
votes
1answer
681 views

Buffer without overlay

Have searched the Interwebs for a few hours now but haven't found an answer to a problem which I thought would have a standard solution. I'm using QGIS to do some analysis on the reach of bus stops ...
6
votes
3answers
2k 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 ...
6
votes
1answer
776 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 ...
6
votes
1answer
839 views

Extracting the pixelwise proportion of classes of a finer raster in a coarser one

I have two rasters, one has a 1 km resolution. The other has a spatial resolution of 30 m. This latter pixelwise is a classification. I want to overlay the 1 km raster on the classification raster and ...
6
votes
1answer
321 views

How to assign (or project) CRS to LiDAR file in lidR?

Can someone enlighten me if there is a difference between initializing a CRS object using the EPSG code versus just the +proj string read from a shapefile? Consider the following objects: A ...
5
votes
7answers
2k views

Problem with Swiss coordinate system overlay in WMS

I have administrative boundaries data for communities in Switzerland from SwissTopo. Original data came in shape files with 'Bessel 1841 Hotine Oblique Mercator Azimuth Natural Origin' projection. ...
5
votes
2answers
1k views

Problem overlapping shapefile and raster in R?

I want to plot a shapefile over a raster file in R but I can't make them overlap perfectly: the raster appears to be rotated of few degrees counter-clockwise. Is it a problem with the projection? ...
5
votes
1answer
1k views

Using satellite background images to draw features in 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 ...
5
votes
1answer
6k 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"> <...
5
votes
1answer
2k views

How to select polygons by points in R?

I have a shapefile with polygons and another one with points. I would like to create a new shapefile with those polygons that don't contain any point inside. I tried the function sp::over in R and it ...
5
votes
2answers
1k views

Calculating edge length of polygon within overlapping polygon using ArcGIS Desktop?

I have a layer of wetland polygons and a layer of lakes. I basically want to find the total length of lake shoreline contained within each wetland and add these values as an attribute of the wetlands. ...
5
votes
2answers
3k 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)
5
votes
2answers
647 views

Finding Raster Overlap within a Directory

Here is the scenario: I have a directory with 100+ map projected, single band, rasters that weighs in a 40GB+. I have used ArcMap's built-in mosaicing tools to create a raster mosaic. I am using a ...
5
votes
2answers
978 views

BBOX and Projections of WMS services in Geoserver

we have tried to overlay a raster layer on Google map and have some difficulties to align the raster images onto the base map. When it is on the overview (Zoom level 1), it looks like this: On a ...
5
votes
1answer
1k views

Difference between lines and polygons using geopandas

I wanted to geopandas.overlay() on lines and polygons : get the geometries from the lines that are not in the polygons. I tried using geopandas for this : result = gpd.overlay(my_lines, my_polygons, ...
5
votes
2answers
4k 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 ...
5
votes
2answers
4k views

How to display KML image overlays in OpenLayers?

I am working on displaying Ground Overlays on OpenLayers by parsing KML manually. To do so, I was trying to add an image on top of Google Map by looking at GroundOverlay section from code.google.com/...
5
votes
1answer
3k 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 ...
4
votes
2answers
453 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 ...
4
votes
2answers
2k views

Overlaying re-projected points and polygons in R?

I am trying to overlay point data with polygons in R in order to find the polygons which intersect with the points provided. The assciated prj file from the polygons shows their coordinate ...
4
votes
3answers
810 views

Is the Intersection Operation Commutative?

In map overlay, is intersection of map layers a commutative operation ie layer_A intersection layer_B = layer_B intersection layer_A? If layer A is a square and layer B is a triangle. In this case, (A ...
4
votes
2answers
2k 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 ...
4
votes
2answers
2k 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 ...
4
votes
2answers
4k views

R: Overlay using functions containing if/else statements

I have two rasters, x and y, and I'd like to do calculations with them using the overlay function. For example, MyFun <- function(x, y) x * y res <- overlay(x, y, fun = MyFun) This seems to ...
4
votes
3answers
851 views

Overlay polygons on raster colour map to extract area values for each colour within each polygon

Does anyone know an answer to the following: I have a set of polygons created as the MCP of animal movements. I also have a habitat colour map raster, with 13 different habitat types as different ...
4
votes
1answer
1k views

ST_RELATE - Intersect ignore shared boundary

Using postgis I am trying to find polygons that intersect, ignoring polygons that only have a shared boundary (edge). ST_Relate(g1, g2, 'T********') is a standard intersection. ST_Relate(g1, g2, 'TF*...
4
votes
1answer
952 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 ...
4
votes
2answers
1k views

Overlaying a polyshape to faceted maps in R with ggplot?

I have managed to create a faceted map from my data following the approach proposed here http://spatial.ly/2013/12/introduction-spatial-data-ggplot2/ with the following code: ggplot(data = plot.data,...
4
votes
3answers
7k 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 ...
4
votes
1answer
2k views

Does OpenLayers supports KML Ground Overlays?

I am not able to display Ground Overlays in a KML file with OpenLayers. Does OpenLayers supports KML Ground Overlays? If not, how would I proceed in writing my own code or plugin for OpenLayers so ...
4
votes
1answer
2k 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 (...

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