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

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0answers
169 views

Can I overlay layers in Dealul Piscului 1970 and WGS84 in QGIS?

I have a 10 Gb ECW file (mosaic of a whole county) that is in Oblique Stereographic projection with Datum: Dealul Piscului 1970. The problem was that no matter the Default CRS for new project was, ...
0
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1answer
819 views

How to highlight track in KML on hover with OpenLayers

I have KML layer with multiple tracks and I would like to highlight them individually on mouse hover. I tried to implement this like in the example found in OpenLayers examples, but couldn't get it ...
2
votes
1answer
1k views

How to deactivate Vector Selection In OpenLayers wms features

This is my sample code and work fine :), But I have a little problem, I'm using multiple layers (WMS), when I zoom the layer will be shown or hidden. In my example bellow when OpenLayers level zoom ...
1
vote
2answers
829 views

Tools/processes that avoid the need for raster to vector converstion?

A "brute force" method of solving GIS problems that involve acquiring values from raster cells and storing them on spatially overlapping vector features is to first convert the raster to a vector. The ...
14
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2answers
353 views

Toward a protocol for encoding vector data as image

This is a follow up to this question: How to create Vector Polygons at the same amazing speeds GISCloud is able to render them? In his answer, Yagi outlines a rationale for encoding geographic ...
3
votes
1answer
919 views

Why is Openlayers KML-layer undefined when using permalink

I am working on Openlayers to dynamically load KML tracks on map. I want it to load filtered KML everytime map is moved or zoomed based on viewport and zoom level. I got it working with code below, ...
2
votes
2answers
2k views

How to set cell size for vector to raster conversion in QGIS GRASS plugin?

I'm converting a vector (loaded in GRASS plugin in QGIS (1.7.0.-wroclaw) and would like to convert this to a raster with a defined cell size. At the same time I need a value from the attribute tabel ...
4
votes
3answers
2k views

Calculate neighborhood statistics for polygons?

I've been searching around for the answer to this (including here) and have yet to find it. I'm interested in finding out how to calculate a 'neighborhood sum' for vector, polygon data. I am aware ...
7
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1answer
195 views

Finding largest number of observations within a given radius

I have the following problem: Given the location of insured properties (say houses with fire insurance), i have to find the largest sum of insured values which fit into a 300m radius. Now, my first ...
3
votes
2answers
500 views

Linear referencing: Assigning RouteIds to polyline feature class

I have a Linear Referencing Route System in ArcGIS Geodatabase format (polylines with M values) and a separate polyline feature class of short segments (called TMC) that do not have RouteIds ...
6
votes
1answer
1k views

Where can I find a Unesco World Heritage List as boundaries?

I was wondering if anyone knows where to find the UNESCO world heritage list with boundaries? I can extract point data from the json feed for the map on the website http://whc.unesco.org/en/list via ...
48
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8answers
9k views

How to create Vector Polygons at the same amazing speeds GISCloud is able to render them?

EDIT (outlining new bounty added): I have added the largest bounty possible to this question in hope of getting a very detailed answer. Your solution should outline a step-by-step guide utilizing open ...
4
votes
4answers
8k views

Looking for an annotated vectorial map of the world

I'm looking for an annotated vectorial (PS/SVG/...) map of the world (+countries). Wikipedia contains many vectorial maps (e.g: http://commons.wikimedia.org/wiki/Category:Blank_SVG_maps_of_the_world ...
11
votes
4answers
446 views

How to generalize coastlines?

I have a large set of data points that essentially represent the coastline of the world. I don't know the exact resolution but I'd say it's in the neighbourhood of 5-10m. Imagine a set of points ...
5
votes
2answers
6k views

Easy way to Create Vector Grid polygons?

We're currently using MapInfo & MapBasic to analyze daily tests results for planning purposes.For each test,exported result may contain empty values (say 999,we know Mapinfo has no NULL values),so ...
3
votes
2answers
934 views

How to combine polygons in a vector with GRASS?

I need to combine polygons of similar geological classes which are stored in a vector file called geology. I was looking for somethiing like "union selected features" or similar. In the GRASS Book ...
6
votes
2answers
802 views

How to check whether a layer is vector or not in OpenLayers?

am not sure whether this is a stupid question or not.. but I am wondering how to dynamically check whether a layer object belongs to OpenLayers.Layer.Vector class. Thanks for any replies!
0
votes
1answer
1k views

openlayers- WFS- Cross-domain problem

I got the typical cross-domain problem when access to WFS layer by using openlayers, XMLHttpRequest cannot load http://XXXX/geoserver/ows?service=WFS. Origin http://XXXX is not allowed by ...
12
votes
3answers
8k views

How to move vectors to specified coordinates in QGIS?

I have a layer of vectors located around, say, (100, 100), and I want to move them to new coordinate like (1000, 1000). How should I do it? Preferably using QGIS.
9
votes
3answers
775 views

In what coordinate systems do true circles appear round?

Please excuse what is probably an obvious question from a relative newB to GIS -- this seems like it should be a snap. I've been developing in Gmaps for awhile and am switching to OpenLayers but am ...
4
votes
2answers
336 views

Vector Analysis: Determining area of county land mass without water features

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 ...
8
votes
2answers
925 views

How to convert a vector boundary to a raster map?

I need to output a PNG file of a raster map overlayed with boundaries present in a vector map. The problem is, the r.out.png script only exports a raster map. My boundaries are in a vector format. ...
4
votes
1answer
2k views

GDAL - creating vector from raster

[SOLVED] Good day! I'm looking at either gdal_contour or gdal_polygonize.py to create a vector layer file from a raster file. I can create the vector file using either method, but it's upside down ...
2
votes
1answer
483 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 ...
6
votes
1answer
6k 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", ...
7
votes
4answers
3k views

How to identify and eliminate overlaying polygons in Quantum GIS?

I have a shapefile with polygons and now, not sure why, most of the polygons became duplicated and overlaid, i.e. when i click to selected one, i get two selected... How do i identify those polygons ...
5
votes
1answer
1k views

How to draw or edit curved lines in free GIS?

I'm searching informations about drawing simple curved arrow lines into free GIS like QGIS, in this problem data geometry is CIRCULARSTRING ( a type which exists in latest postgis version) It seems ...
6
votes
1answer
4k views

How to create a point along a line given distance

I have been given a non-spatial database which contains the names of lines which I have a shapefile for. The database also has names of points and the distance of each point from the origin along the ...
2
votes
0answers
471 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 ...
3
votes
1answer
2k views

Extract parcel layers from vector pdf

So, I have an interesting problem... I have a PDF file which has over 100 pages and each of these pages is displaying a map in vector format. By using some third party program I was able to find out ...
16
votes
2answers
7k views

How to Import SVG into GIS?

I have a PDF file, with a Map as a vector graphic. I want to get this into GIS. (I use ESRI's ArcGIS, but any FOSS solution is also fine). I know that it is not possible to directly get the PDF into ...
4
votes
2answers
1k views

Stylized map workflow: Illustrator to Google Maps / OpenLayers

The aim My current aim is to create a series of (heavily) stylized diagrams and maps. I'm not very familiar with any GIS software, so my weapon of choice would be to use illustrator for creating the ...
3
votes
1answer
1k views

Openlayers Add features performance for 3000 lines

We would like to implement the function of Addfeature in openlayers to draw lines and push them onto a vector layer, and overlay this layer onto open street map or google map. Those lines are draw ...
1
vote
1answer
210 views

Any freely available vector data in cylindrical projection?

I'm trying to develop an application in PHP to plot various points in Europe from a database, and serve them dynamically on a map. I think this should be relatively straightforward when using a map ...
2
votes
1answer
783 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
3answers
1k 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 ...
15
votes
1answer
24k views

Programmatically creating a vector feature in OpenLayers

I want to create a vector feature, programmatically, on my map. It's supposed to be in the A4-paperformat, for showing a sort of print preview. I've created a control for handling this, but now I'm ...
27
votes
3answers
25k views

How to clip a raster with vector boundaries?

I am using QGIS. I would like to clip a raster precipitation layer using an admin boundary layer that is vector data. However the geoprocessing tools seem to be usable only for vector data. How can ...
4
votes
2answers
4k views

Reclass for vector data in ArcGIS

I've got a vector dataset (in fact, OS MasterMap data) and I want to set the value of a certain field based on the value of another field. For example: Field1 Field2 Building 20 Grass ...
12
votes
6answers
5k views

Converting GeoPDF to vector format like CAD or shapefile?

I want to convert a GeoPDF that has vectors entity in it to a vector format and preserve the real coordinates of these vectors. The GeoPDF has been exported from ArcMap and has layers in it. I have ...
4
votes
1answer
4k views

Relabel Vector Points in OpenLayers

I have created two labeled vector points on an open layers map. I'm trying to change the label text dynamically. I tried changing the values where the stylemap gets the values from and calling ...
6
votes
3answers
6k views

Finding nearest raster cell value based on vector point?

I have two layers in ArcGIS: One is a vector point and the other is a raster layer. I want to append the value of the raster data grid to the vector point. The problem is the vector point is away from ...
3
votes
2answers
124 views

Obtaining OS MasterMap time series data

I am trying to do a research project on changes in Land Cover in a London borough over time. I have access to OS MasterMap data through Digimap (the service that provides this data to universities in ...
3
votes
2answers
192 views

Is there a shortcut in GRASS for importing vector files?

Is there a keyboard or command shortcut in GRASS for importing vector files? If you know link where I can find maybe whole list of shortcuts for GRASS, that would be awesome. Thank you.
3
votes
5answers
3k views

Export shp spatial data to Corel

Hi I need an printable administration map of a country. I would like to use it in Corel Draw for some colour manipulations and poster printing. I have found the map on http://www.diva-gis.org/ but it ...
3
votes
0answers
1k views

How to get turn angle, line orientation and line length in ArcMap 9.3.1?

I am mapping and analysing animal movements using arcgis 9.3.1 along with Hawthorne Beyer's GME, and am trying to utilise the correlated random walk commands, but in order to do this I need to find ...
3
votes
1answer
4k views

Reproject a vector layer (EPSG:27700) using WFS onto a googlemaps background (EPSG:900913)

I have the following HTML-javascript code and i have problems reprojecting the vector layer (WFS) from EPSG:27700 (British National Grid) to EPSG:900913 (googlemaps). I managed to project the WMS ...
8
votes
3answers
11k views

converting kml into a vector graphic… and back

Is there a simple means to convert, say, an svg or other vector image format file to KML and vise versa? There are incredibly powerful vector editing tools which attempt to replicate the way reality ...
3
votes
3answers
778 views

How do I draw on a vector map in GRASS?

I have a vector map that has two lines. I want to have the two connected. Is there a way for me to draw a line to connect the two? I am using GRASS gis by the way. The two lines that I want to connect ...
4
votes
5answers
689 views

How to save a raster and vector into a single PNG file in GRASS?

I am trying to save a raster and vector into a PNG file. The vector is overlayed on top of the raster map. I was only able to save the raster file into a png using r.out.png but without the vector.