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

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1
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2answers
359 views

OpenLayers: WMS layer above select-controlled vector layer?

Is it possible to display an image layer (WMS or Image) above a vector layer with activated SelectFeature control in OpenLayers? The image layer (radar returns) contains only sparse, semi-transparent ...
5
votes
1answer
138 views

LiDAR Feature extraction specifications/standards

I have vector data representing forests/trees/buildings that have been automatically extracted from LiDAR data. I am looking for specification/guidance for LiDAR derived products, or any standard for ...
2
votes
1answer
251 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 ...
1
vote
2answers
98 views

QGIS point sampling tool really slow for polygons?

I have a large field of randomly distributed points (100,000 of them to be precise), and I'd like to get values for a variety of raster and polygon coverages for each point. I've been using the QGIS ...
3
votes
2answers
278 views

How to calculate distances between addresses and cities and coast line?

I am totally new to GIS, and so I apologize if my question is not clear enough. My basic problem is the following: I have about 160,000 Danish addresses with longitude and latitude for each address. ...
17
votes
4answers
10k views

How do I load OSM vector data in QGIS 2.x?

In QGIS 1.8 I used the openstreetmap plugin to request data from the server, or open a .osm XML file, which produced 3 layers (polygons, polylines and points) in QGIS. This was great (give or take the ...
2
votes
2answers
228 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 ...
0
votes
1answer
813 views

Convert vector data with irregular points (no grid) to raster with QGIS?

I am aware that how to convert a vector layer to a raster layer is a quite frequent problem and that there are many questions and answers dealing with it. However, none was helpful concerning my ...
2
votes
1answer
123 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 ...
0
votes
1answer
105 views

How to increase symbol size of polygons when zoomed out?

I have many small polygon scattered. How do I increase size of polygons when zoomed out in qgis? As seen in the image the symbol appears to be lost when I zoom out. Note: I have created a thematic ...
0
votes
0answers
99 views

Google and Croatia WMS do not line up with shapefiles (500 meter to East)

I am working on a project in Croatia. I can use the WMS files from geoportal.dgu.hr/wms. These line up perfectly with the google maps. As project CRS I use HTRS96/TM which has become standard in ...
0
votes
2answers
64 views

v.what.rast trouble in GRASS GIS 6.4.2

I'm facing a problem using the v.what.rast comand. I'm trying to update the vector "canali" which represents some streams, with the slope value for every single point of the lines. The slope values ...
2
votes
1answer
228 views

How to calculate mean coordinates from big point datasets?

I know there are several questions related to speed issues in QGIS, but I am having problems when running Ftools. I have a vector with ~70,000 points in it. When I run the generate mean coordinates ...
0
votes
2answers
149 views

In grass v.drape works with points but not lines

I got an elevation raster map which I interpolate from a point cloud with v.surf.bspline. Then I digitize a couple of points in a new vector layer. With v.drape I'm able to get a height from the ...
2
votes
1answer
47 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 ...
1
vote
1answer
81 views

Snap mean coordinate to layer in QGIS and creating MCs for multiple shapefiles

1: I wish to create a mean coordinate for a group of points. However, I would like the new point to be snapped to the nearest point from the set of points used to generate it. How might one go about ...
-1
votes
2answers
92 views

Counting raster points within boundaries in another layer?

I know this question is similar to some out there, but I have tried all the 'solutions' and none of them are working for me. I am using the latest version of Qgis. I have a raster layer with ...
0
votes
2answers
90 views

please Introduce me a free 3rd party library appropriate for showing Geospatial information

Up to know I have used GDAL to extract raster data from geotiffs and then opengl's used to show that raster data. But when it comes to extract vector data with the help of ogr library, what library ...
0
votes
0answers
163 views

How to read vector datasets using GDAL library

Up to now, I have used GDAL in order to read raster information and geotiffs and show them with the help of OpenGL. Now I have a vector dataset, and by that, I mean I have the files with types: DBF ...
1
vote
2answers
603 views

OpenLayers vector does not draw (or re-draw) on zoom level change or layerswitcher off/on

Here is the full code (i'll highlight the important parts after): jQuery(document).ready(function($) { // ...
3
votes
0answers
132 views

Cross-browser marker animation in OpenLayers

Currently I'm trying to implement animated markers in OpenLayers. I'm using PNGs for the markers, set by the externalGraphic style property on an OpenLayers.Layer.Vector. I need to be able to make ...
0
votes
0answers
77 views

vector layer does not render points after modifyFeature

I'm implementing an appication with openlayers 2.12. Gets features from Geoserver after CQL search. Now, when the users clicks on one point/line/polygon, gets textual info via websockets (nodejs) for ...
0
votes
0answers
102 views

How to create a Layer from a list of points in PyQgis

I`ve developed an algorithm that generated an two dimensional array with points. Each subList of this array must be displayed as an polygon on the map view, and the recently created Vectors should be ...
0
votes
1answer
603 views

provide an alternative “label” when styling vector layer with openlayers

I'm using openlayers 2.12 and I am styling a vector layer using your typical new OpenLayers.Style({ Now, this layer does two things. First , renders polygons from Geoserver, so in the style I have ...
2
votes
1answer
69 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 ...
1
vote
2answers
291 views

Custom filters (server side) for Openlayers Vector Layer

I have a vector layer in openlayers with source in GEOJSON (custom php server, which I have in complete control) and BBOX strategy. Vector points contain point sources which have different ...
2
votes
2answers
508 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 ...
0
votes
1answer
130 views

OpenLayers Strategies

Can we use the strategies OpenLayers.Strategy.Fixed and OpenLayers.Strategy.BBOX simulataneously on same vector layer?
1
vote
1answer
773 views

Running Maperitive on a Mac

Really basic question, but I need details and help running Maperitive from my mac. I've tried launching it from the terminal and tried running it through WineBottler. If anyone has experience with ...
1
vote
1answer
226 views

reclassify vector data from multiple source data fields (ArcGIS) (ModelBuilder)

I am using ArcGIS 10.1 and ModelBuilder. I am not familiar with Python. My question is very similar to ReClassify Vector Data Between Values . However that question is about reclassification using ...
1
vote
0answers
156 views

Loading Vector Layer PyQGIS Issues

I am trying to follow PYQGIS documentation for loading a shapefile from inside a script. http://www.qgis.org/pyqgis-cookbook/intro.html I was able to set the datasource and run the QgsVectorLayer ...
0
votes
0answers
71 views

Vector/Raster Intersection - Speedup and replacement for ST_Centroid

I have some raster data which is the altitude above sea level and also some vector data which represents building outlines. What I want to do is grab some buildings outlines and fetch all the raster ...
2
votes
0answers
177 views

How to render a transparent raster layer on top of one or more vector layers with PyQgis?

I been trying to render a map with a 3 vector layers and one raster layer. The idea is that the raster layer should be on top of the other 3 vector layers. The problem is that even when I add the ...
2
votes
2answers
165 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. ...
1
vote
0answers
102 views

convert vector with multiple attributes to multiple rasters

I have a vector polygon feature with multiple attributes/fields. Ultimately, I want to convert it to a raster 'stack,' whereby each of the attributes/fields will be a different band of the raster ...
8
votes
2answers
261 views

Creating an “average” polygon

I found this thread in the old ESRI forums with the same type of problem I am facing today. The solution to the problem is explained in little detail and since I am not an expert, I was wondering if ...
0
votes
1answer
66 views

How to edit a table in GRASS?

How do I edit a table in GRASS? When importing a vector into GRASS from QGIS, all the attributes are lost and I need these to continue with my analysis.
0
votes
1answer
435 views

OS Vectormap GML files into PostGIS

I am having difficulty in efficiently dealing with OS Vectormap data that comes in GML format. In the past I used the Plugin for QGIS (OS GML Tools) to batch convert folders of compressed GML (.GZ) ...
1
vote
1answer
60 views

Area surface doesn't match

I have three municipalities with a total surface of 178 sq km. I want to analyze land cover of those municipalities using both LANDSAT images with a pixel size of 30 x 30 meters and SPOT with a pixel ...
1
vote
0answers
45 views

Align OpenLayer raster with OS Mapping Vector

I have an OS Vector map of a town in Ireland. When I load the Google Satellite Raster from the Open Layers plugin, the results are slightly off, by about 2m, probably due to ariel persepective. I'm ...
1
vote
1answer
296 views

Add a popup to a Vector LineString in OpenLayers?

Is it possible to add a popup (without a marker icon) to a Vector (LineString)? This is my code, if possible, how to change it to add the popup? I need the popup to display some additional ...
0
votes
1answer
105 views

show dwg,as background not as vector

I have some dwg files that i need to show as background on my map, but the DWG is not need to be vector layers, i need only to show them with out the need of using. if i am trying to convert it to ...
0
votes
1answer
172 views

Sum of values within a buffer polygon

I need to do the following in QGIS and hope so much anyone could help. I have a vector layer with points. Each point represents a firm with the number of employees in the attribute table. I want to ...
1
vote
0answers
61 views

Can I edit WMS layer or KML layer?

I am using Openlayers and until now i have been using OSM as background and i got points from my db (mySQL) and add them to vector layer, then i could modify them and save it back to the server. now i ...
2
votes
0answers
51 views

Moving legend items up and down in QGIS

How can I change sort order in layer properties styles tab? The only way I've found is to change their labels and order by it.
3
votes
1answer
59 views

Speeding up raster to point set function

I have written the following function that takes a raster (always non-skewed) and returns a set of points. As I'm executing it millions of times in my queries, I'd like for it to be super-optimized ...
0
votes
0answers
180 views

Issues when importing line shapefiles into NetworkX

Note that although I am using Python Console from within QGIS for this, I don't think it's a QGIS issue. Below is the difference of how NetworkX is dealing with 2 line layers created by the same ...
2
votes
2answers
72 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 ...
1
vote
0answers
197 views

Line segment connectivity analysis in FME

I have a set of line segments, all of them snapped at the endpoints: As seen in the above image, the line segments appear in groups (4 in this example). Question: I would like to determine which ...
4
votes
4answers
1k views

How to get vector data from OSM to use in QGIS?

How do I get data from OpenStreetMap which I can then edit in QGIS layer by layer? What is the best OSM output and what / how do I get to a suitable input for QGIS? OR...is there another appraach to ...