A coordinate-based data model that represents geographic features as points, lines, and polygons.

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366 views

Styling OS Vectormap Local in QGIS?

I am attempting to style Ordnance Survey Vectormap Local on QGIS 1.8.0 by using the styling sheets suplied by Ordnance Survey. The styling sheets are available from the OS website ...
2
votes
1answer
3k views

How can I update the label of a Polygon Vector after it has been drawn?

I am quite new to OpenLayers. Right now, I have a polygon vector with some styling applied and a label. var style = $.extend(true, {}, OpenLayers.Feature.Vector.style['default']); style.pointRadius ...
2
votes
1answer
84 views

graduated labels in QGIS

I've searched on Google but haven't found an answer. The QGIS Dufour GIS provide an enhanced vector-styling interface but is it also possible to graduate the labels like it is possible for the ...
2
votes
3answers
121 views

Ordnance Survey 1 km Grid

I am wanting to get a copy of the OS 1km Grid layer. I have found these previous questions: Ordnance Survey grids - download or generate? and Ordnance Survey Grids But neither provide the ...
2
votes
1answer
50 views

How to change layer transparency without changing border lines?

I have a raster image of elevations. I have added a vector shapefile that contains local political divisions. I want to keep the elevation colors, but I want to keep the black lines representing the ...
2
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4answers
143 views

High resolution and high detail vector GIS coastline product needed

What is the absolute best vector GIS coastline product available globally? I know of a great product for Africa (page 13 of this PDF ...
2
votes
1answer
130 views

How to best execute the same query on many different vector layers?

I have some vector layers in my project and I need to separate the polygones by area (I need a copy of all shapes > 2ha). I know how to do this for each separate layer (query) but is the a tool to do ...
2
votes
2answers
77 views

How to 'trace' areas from the layer below?

I have some Ordnance Survey vector data for my local area. I want to create a new layer and on it 'trace' some of the areas, fields, verges etc from the layer below with the intention of then ...
2
votes
2answers
690 views

How to render a multi-layered (raster + vector) map to a file (PDF, SVG or JPEG, PNG)?

When using OpenLayers I can compose a map with several layers which is displayed nicely by my browser, but I need to do the same server side (no browser composing the layers), and I'm waiting a image ...
2
votes
1answer
1k views

How to export vectors from QGIS to MapInfo?

I am trying to save some vector lines that I made in QGIS (1.8 Lisboa) to a format that can be added to MapInfo Professional 6.0 (ancient version I know..). When I save the vector to a Mapinfo ...
2
votes
2answers
288 views

How OpenStreetMap data layer works?

OSM map has a data layer and an information panel. How is it implemented? What is a type of the layer and URL of vector data source? How information panel works? Thanks for all!
2
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1answer
40 views

Why do layers appear in the wrong order in QGIS 2.2?

I have a problem with in which order my vector and raster layers appear in QGIS. I have raster that I want to be the background of my other layers (vector). I place the vector layers on top in the ...
2
votes
1answer
607 views

OpenLayers Vector Layers: adding and removing features VS. redraw/refresh

I am currently using addFeatures and removeAllFeatures in my code to get the desired results and this is working OK. However, I have been asked to ensure that the vector layers are not being ...
2
votes
1answer
63 views

Is it possible to display two categorical symbolizes for two different attributes in one layer alongside each other in ArcMAP 10.1?

I have a road layer that I would like to display attribute_1 = "speed" on top of the line segment and attribute_2 = "traffic_volume" below the line segment. For each attribute I would like to setup ...
2
votes
2answers
85 views

How to overcome the layer limit on OSX?

I am trying to add many layers to a project in QGIS. After adding approximately 80 layers, QGIS returns this error: "not a valid or recognized data source". There is nothing wrong with the shapefiles ...
2
votes
3answers
1k views

Openlayers: Copy shape layer in a vector layer

I have a web-gis application based on openlayers and geoserver. I need to modify a shape layer. I'm able to show the shape using the OpenLayers.Layer.WMS method. In fact i published the shape in ...
2
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3answers
2k views

Openlayers get coordinates from polygon

please could someone help me and bless me with an example of how to get coordinates from a polygon in OpenLayers?
2
votes
2answers
366 views

How to combine vector layer and wms layer based on some constraints?

I would like to group wms and vector layer together but with some constraints in openlayers. The requirement is, if lets say vector layer 1 is selected then its corresponding wms layer should also be ...
2
votes
2answers
1k views

How to query which features of all vector layers intersect with a given bounds?

I am writing a Openlayers map app, and wondering whether there's a better practice to query which features of which vector layers intersect with a given bounds.. It's certainly not a good idea to ...
2
votes
1answer
393 views

polygon map overlay algorithm

There are many algorithms for binary map overlay operation in vector data format which take two layers of map and produce resultant layer i.e overlaid layer as output. I am wondering whether there are ...
2
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3answers
969 views

Convert Arcgis Rest to OpenLayers Vector

i am working with openlayers and esri rest services... in my api due to esriGeometryPolygon for all city , rendering map is taking lots of time ..there for i dont take a good result.. first of all is ...
2
votes
3answers
79 views

How to prepare a multi-colored vector layer?

I need to present a multi-colored vector layer and something similar to below: I need to prepare the vector layer by making use with the data set available in my database. Inside my database, I ...
2
votes
1answer
107 views

How to delete points which are close to each other?

I have a vector file containing thousands of points. Where points are within x distance from each other, I wish to delete one of the points and keep the other (either by snapping to one point, or ...
2
votes
2answers
64 views

cutting and extending one polygon layer in function to the other layer boundaries

I'd like a methodology that can edit my vector layer, extending and cutting the features in the polygon layer "cap_agricola" within the boundary layer "sp_edr", I would like to solve this problem in ...
2
votes
1answer
881 views

How to get attributes of overlaying polygon layers by a spatial query?

I am new to QGIS and would like to merge selected data/attributes out of the attribute tables from overlaying vector objects on different vector layers without creating new additional layers. Is ...
2
votes
1answer
102 views

How to close and fill Gulfs and inlets in QGIS or Grass?

I have a raster layer from which I extracted only zones with a certain color, then polygonized it with QGis. I just generalized the new vector layer in GRASS to smooth things a bit. There are many ...
2
votes
1answer
616 views

LoadingPanel - Waiting for Vector & WFS loading

I have vector layer with WFS protocol. and because I have a huge amount of data, there is a while before features loaded on the map. So i need to tell user to wait a moment until they load by ...
2
votes
1answer
124 views

Is there anywhere that I can obtain global UV data in either raster or vector format?

I'm looking for some UV data (currently with no spatial or temporal resolutions in mind, but ideally split into UV-A and UV-B) for the whole earth. Can anyone recommend a source for data like this or ...
2
votes
2answers
167 views

Determine the furthest driving distance from a road layer to the nearest point of a point layer using OSM/QGIS

In a specific geographic area, I have a road layer and roughly 30 points dispersed around the geographic area as part of a point layer. Both layers are in SHP and PostGIS formats. The records from the ...
2
votes
1answer
495 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 ...
2
votes
1answer
549 views

How to clean vector segment intersect errors in GRASS

I'm using GRASS to process a vector map. When I export back to .SHP and do a 'Check Geometry Validity' in Quantum GIS it lists several errors of this type... 3,segments 199 and 203 of line 0 ...
2
votes
2answers
71 views

How can I get repeated vector grid in horizontal direction?

I need to get repeated vector grid layer in horizontally direction. I created many polygon vector grid layers, and their extents as listed bellow (Xmin-Ymin, Xmax-Ymax): Layer 1: 5910000 3040000 ...
2
votes
1answer
170 views

Possible workflows for shaded relief representation as vector

I am looking for a good workflow on how to represent relief on a map as vector (e.g. for further processing in Adobe Illustrator or Inkscape). My inspiration is the present google maps at zoom level ...
2
votes
2answers
107 views

Georeference vector linework

I'm new to GIS and a lot of searching didn't answer my specific question so far, so I hope someone can help me here. What I want to do is creating a small web application to visualize election ...
2
votes
1answer
45 views

Conceptually, what's the ideal way to develop detour maps for a large number of nodes

I have a road layer of roughly 30,000 links. On these links, I have a total of 15,000 nodes that are sorted in a point layer. I'm trying to build a detour distance and routing around each asset in ...
2
votes
2answers
131 views

Convert ASCII Grid Colorized to Raster

I have an ASCII Grid file + .prj file and can visualize this in qGIS. I can colorize it by going to properties and using a Pseudocolor Ramp. However, I want to export this now as a TIFF / Raster. ...
2
votes
1answer
97 views

How to stop features to redraw unwillingly in OpenLayers

I have a problem where when editing features from a wfs vector layer. After some changes are made to the geometry, the feature redraws itself and the changes are lost. Usually the problem occurs more ...
2
votes
1answer
482 views

How to remove a vector QgsVectorLayer from QGis python plugin

I managed to add QgsVectorLayer in QGIS through a python plugin, for example: vl = self.iface.addVectorLayer(uri.uri(), layerName, self.dbConn.getProviderName()) But how can I remove it?
2
votes
1answer
559 views

How to correctly merge layers with overlapping polygons in QGIS/GRASS?

I have 4 vector shapefile that I would like to join/merge, without worrying about attributes. Here are the shapefiles. I would like to do an union and a spatial dissolve, but everytime I do a dissolve ...
2
votes
1answer
103 views

From Raster to Masked and Filtered Polygon Vector

I have a set of rasters (geologic risk) from which I want to extract zones with a specific color, clipping them with a polygon (administrative borders), outputting a shapefile. I'm using QGis (and ...
2
votes
1answer
399 views

GML and GeoJSON vector layer can not display in Firefox and Chrome

I have following codes. It works perfectly in IE (GML and GeoJSON vector layer was loaded), but not in Firefox and Chrome without any errors noticed. Please help me to fix this problem. Here is the ...
2
votes
1answer
2k views

How to change an OpenLayers vector layer from automatic to manual get request?

I have a web server that returns a FeatureCollection in JSON. I was getting this using the code below, which works perfectly: var vectorLayer = new OpenLayers.Layer.Vector('geoJSON', { ...
2
votes
3answers
2k views

Change zIndex of Vectors in openlayers

I have a bunch of linestring features on a vector layer. Some of them overlap. If I trigger the hover event on those features, I want them be in front. I did find some functions to set the z-index of ...
2
votes
1answer
562 views

Loading Raster and vector data In MapGuide using Maestro

I am new to Mapguide , working on it for my summer Internship.I have Installed it perfectly. Now the task is to load vector data and Raster data in map Guide (mainly have to load *.shp files and *.tif ...
2
votes
2answers
708 views

Multiple Maps with Styles not working in OpenLayers

I have created 2 maps(within 2 in a same page) along with their respective style maps. Both maps are having vector layers along with "LineString" geometry... added into them. Both style maps are ...
2
votes
1answer
102 views

Keeping a vector layer always on top

I want to know how to keep a layer always on top of other layers! After adding a vector layer ( QgisInterface->addVectorLayer ), I want that layer to always be displayed on top of layers added later. ...
2
votes
2answers
1k views

How to create dynamic map images?

I have map images of my local ward (Areas geo-referenced and drawn using QGIS and Adobe illustrator. Now these maps are in .png format (Raster images). It's not a tile linked to some mapserver such as ...
2
votes
1answer
448 views

Why does intersect not calculate polygon areas?

this is strange: I intersected 2 shape-files and the resulting shape does not contain the Shape_Area and Shape_Length of the intersected polygons. Instead the field Shape_Area contains the ...
2
votes
2answers
540 views

How to query data from a vector map (shapefile)?

We want to obtain the specific place of the boundaries of a shapefile. We want to be able to get the points of each polygon corresponding to a specific place in order to use these data in an ...
2
votes
3answers
82 views

How to get a bbox selection of huge shapefile as GeoJSON?

I have a 4.29 GB Shapefile from which I want to extract features as GeoJSON, defined by a bounding box. This should be as fast as possible, because I want to use it in a web application. My first ...