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How to retrieve PROJECTION value for a map?

I am trying to read the Projection from Geotiff/shape file, using gdal 1.9.0 by the following command in the command line... gdalinfo.exe -proj4 map-path but its retuning empty string for ...
2
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0answers
39 views

How do I get the domain from an OGRSpatialReference?

I would like to know what the projected bounds are for a spatial reference using OGRSpatialReference. Is there some way to use the GetProjParm method to get this information? An example of what ...
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1answer
91 views

Using the C++ GDAL API how do I set the GDAL_DATA path?

If I want to change the directory of the GDAL_DATA path or point to a different version of a csv file for EPSG numbers how do I do that using the C++ API?
2
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1answer
302 views

QGis Plugin Licence

I would like to create a plugin using commercial software. Does the QGis licence permit this? Are there any restrictions on the licence I can choose to apply to my plugin?
3
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2answers
502 views

circle detection on binary image

My image is gray scale image which i have converted to binary by smoothing and then edge detection method. Now i want to place the circle /ellipse on edge detected. I don't know how to proceed ...
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0answers
113 views

How to extract an adjacency matrix from OSM?

I would like to use graph algorithms from the Boost graph library on OSM data. What are my choices to use Openstreetmaps data from within a C++ program ? I need at least a flat file with a list of ...
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1answer
108 views

Featureclass search failing in C++. But working in C#

I need to perform search on a FeatureClass using ISpatialFilter for a given Point (x,y). I wrote a program in C# to do that and its retrieving the features as expected. But the similar program in C++ ...
1
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0answers
43 views

how to get correct geo reference system for a VMap

I am new to GIS, trying to read the GeoRef System for VMap by using the following code: OGRSpatialReference *ref = layer->GetSpatialRef(); if( ref ) { QString georefSystem = ...
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1answer
517 views

QGIS Plugin Windows

I have written a QGIS plugin (RTools) which acts mostly like a independent plugin (minimal interaction with QGIS core functions). On Linux both QGIS and RTools were build using QT 4.8 on Qt creator. ...
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1answer
445 views

PROJ4 C++ API: Amersfoort RD New to WGS84

I try to convert between dutch RD New (EPSG:28992) and WGS84 (EPSG:4326) via PROJ4 C++ API. On the console this works with: cs2cs +proj=sterea +lat_0=52.15616055555555 +lon_0=5.38763888888889 ...
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0answers
74 views

Developing QGIS Plugin on windows [duplicate]

I have developed a small plugin which acts as a plugin for QGIS. On linux, QGIS (customized) as well as the plugin were built using QT creator and worked well. Same code I am trying to port on to ...
1
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0answers
139 views

using GDAL/OGR (faster)

Eventually, I was able to get the GDAL installed and compiled correctly using Visual C++ 2010. I even tested some of its methods on some geo-referenced raster files, and it looks like that all is ...
2
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1answer
246 views

Compare two Digital Elevation Model (DEM)

I would like to know what's the best method(s) to compare two DEMs without using any GUI soft like QGIS or ArcGIS. I'd like to do it in Python or C++, with GDAL or other similar lib. Does calculating ...
2
votes
1answer
84 views

Create ERDAS IMG Statistics using GDAL C++ API?

I want to create very many ERDAS .img files using GDAL under C++. I don't want to have to process them all in ArcMap to create statistics for them (mainly because ArcMap fumbles when calculating ...
0
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1answer
300 views

Most optimal algorithm for contour correctness?

Am creating an app which correctly calculates contours from a DEM file or any height-map given to it. The correctness of the contour holding the most importance, since a person viewing the contours ...
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0answers
94 views

OSGB36 referenced PNG to Google Earth

I am creating a PNG that is referenced to the OSGB36 datum (1 pixel per 50m easting/northing that is colored according to the result of some calculation code) I want to display this on Google Earth ...
1
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3answers
1k views

How to subset raster image using gdal?

I have read pixel values of an raster image using GDAL libraries in visual studio 2010(vc++). Now I have to crop the image (subset) according to the grid given in shape file. I have got a code for ...
1
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1answer
124 views

Get the keyPress-Event in QGis-Plugin

I have a QTreeWidget in a QWidget which is the gui of my plugin(cpp). Now i want to get the keyPress-Event of a Node in the TreeView. I try to reimplement the signal of the QWidget. protected: ...
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1answer
172 views

How to set the cursor to busy mode?

How can I set the cursor to busy-mode/in progress from my qgis plugin (cpp)? I couldn't find anything in the API documentation.
5
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1answer
359 views

Slow FileGDB Performance in GDAL

I am attempting to write many ASPRS LAS point files into an ESRI File Geodatabase using my compilation of GDAL 1.9.2. The FileGDB driver for GDAL/OGR appears to be incredibly slow when writing large ...
3
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1answer
467 views

How to get elevation with LibGeoTiff?

I'm trying to get an elevation profile from a geotif file ( downloaded from http://srtm.csi.cgiar.org/). I downloaded the libgeotiff library but i can's see any function that can return an elevation ...
2
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0answers
54 views

Is there a way to distinguish between digitized and pasted features?

Is there a way to tell if an added feature in QGIS is in fact a newly digitized one or a pasted feature? I think QGIS is treating both cases in the same way, emitting the same signal: ...
4
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1answer
84 views

Is it possible show the feature attributes dialog when I add a feature in code?

I want to know if it is possible to make the feature attributes dialog in Qgis show up when I add a feature by code using: QgsVectorLayer::addFeature( tFeature ) This is available when I add ...
6
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1answer
445 views

How to get latitude, longitude and altitude database from a GeoTIFF file?

I am developing an AR iOS application. When the iPhone gets the current location, it has to calculate locally the visible point. I want to read the tiff files in my application, and then get the ...
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2answers
1k views

How to implement viewshed calculation?

I'm looking for a way to implement visibility (aka viewshed). I found a previous GIS SE question that suggested a few GIS applications (not what I need - I'm trying to embed the calculations), and ...
3
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1answer
416 views

How to use GEOS/C++ to efficiently find all point pairs closer than a threshold?

Can anyone tell me how to use GEOS/C++ to efficiently find all point pairs in a dataset closer than a threshold distance d? I suspect this might involve quadtrees or rtrees but not quite sure how ...
5
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1answer
617 views

Where can I find documentation on QGIS C++ Plugin Development?

Is external C++ plug-in support available for QGIS? I'm having a really hard time getting started here. I followed the doc here: ...
2
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3answers
217 views

Given (lon,lat), how can I quickly retrieve the containing administrative region?

Given a coordinate (lon,lat), I'd like to retrieve the containing administrative region (state/province level) for an offline mobile application. The method employed needs to be fast/efficient. ...
6
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1answer
674 views

C++ Code Examples in Quantum GIS 1.8

I am trying to utilize the C++ code examples from blog.qgis.org, specifically Tutorial 4, Adding Rasters to QGIS Map Canvas. I am successfully able to run the example loading a GeoTIFF with QGIS ...
3
votes
3answers
295 views

Installing the development files libqgis-dev in Ubuntu 12.04

I am trying to install development files which include the headers and the libraries for qgis in Ubuntu 12.04. I used Ubuntu software center, synaptic and the terminal and am still getting the same ...
2
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0answers
241 views

Setup of development environment of QGIS on windows with qt creator

Can anyone help me in setting up environment for working on QGIS on windows using qt-creator? I am using qt creator version 1.3.1,qt version 4.6 and QGIS version 1.8. Thanks.
1
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0answers
149 views

gdallocationinfo from C++?

I need a C++ API to convert x,y Image Coordinates in their native projection to output image pixel,line coordnates. I see the gdallocationinfo documentation, but no API for it. Where in online GDAL ...
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3answers
371 views

Getting Field value for a given coordinate out of ESRI Shapefile using GDAL/OGR

I have a bunch of ESRI shapefiles that contain Land Cover data across Canada (provided by Geobase). I need to query the files and obtain the value of a certain field (called COVTYPE) in a given ...
5
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1answer
1k views

Setting up an application in QT Creator that uses QGIS API

I am a 15 year veteran of Java making my first entry in to C++ applications. I have a specific need to develop a desktop application that produces graphics type output as well as displaying imbedded ...
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0answers
78 views

Connect to Esri map service using c++ in stand alone desktop app

Can anyone tell me how to do this? Here is my code. The Open call returns E_INVALIDARG. IAGSServerConnectionFactoryPtr AGSConnectionFactory; ...
1
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2answers
121 views

Fetching field values from uncommitted features on Qgis

I'm trying to fetch a feature's field value on Qgis, I use QgsFeature.attributeMap().value(cont int & key).toDouble() This works fine for committed features but it always returns " 0 " if the ...
0
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0answers
19 views

Storing Image data to spatialite [duplicate]

Possible Duplicate: spatialite storing raster data I want to store geotiff data to spatialite databse. I am using gdal to read metadata and reading tiles convering them to hexwkb format and ...
1
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0answers
241 views

What do I need to build a C++ plugin on windows 7?

I want to make a plugin in C++ and I need to write and build it in windows (Im better with *nix systems). While I have skimmed the various updated C++Plugin docs I can understand if I need to build ...
1
vote
1answer
176 views

postgresql pgrouting define C function function with int* arguments

I want to create a psql-C function with an undefined length list of integers (GIDs for example). An erratic example using V0 function definition that works is like: int mytest4(int *x, int i){ int ...
4
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1answer
678 views

How to store raster data in spatialite?

I want to cache my raster data(large geotiff files) on local database. I thought to use spatialite. I found librasterlite which provide functionality to do that. Can anybody point to some tutorial on ...
0
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3answers
309 views

raster data retrieval from postgis using c++

I have raster data in a postgis server (I am able to see it in qgis). When I retrieve it and form gtiff image out of it using gdal, the generated image is not correct (there is a coloring problem). I ...
0
votes
1answer
157 views

Qgis : QGraphicsTextItem's position not updated?

I'm using QgisInterface->mapCanvas()->scene()->addItem(QGraphicsTextItem) to add a QGraphicsTextItem to the map canvas. The problem is that when I use the pan tool to move the display the added ...
1
vote
1answer
984 views

Convert Lat/Long to UTM specifying which zone to use (C++)

I need to convert Latitude/Longitude coordinates into UTM, in C++, specifying which zone to use. I am working with locations that fall in two zones, and would like to project them all into one zone - ...
2
votes
1answer
177 views

Qgis C++ plugin translation

I'm having issues with the translation of my Qgis plugin. static const QString sName = QObject::tr( "Editeur Monoscopique 3D" ); MyClass::MyClass( QgisInterface * theQgisInterface ): ...
7
votes
1answer
1k views

How can i create sectors for telecom towers

friends i am seeking advice from the GIS community I work in the Mobile networks industry and i took up a task to create a plugin for QGIS using c++/python that does the following: step 1: Create ...
2
votes
2answers
322 views

C++ coordinate class that automates projection?

Can anyone point me to a C++ class for representing coordinates that automatically handles projection transforms? What I'm thinking of is something that would allow me to create vars that incorporate ...
2
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1answer
280 views

How to port QGIS C++ plugins to other QGIS installations?

I developed a C++ plugin for QGIS using VC++ express 2008 and a QGIS dev release (1.9.90 alpha), my plugin works fine on this release and now I want to port it to other QGIS installations, so I copied ...
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0answers
21 views

MapCanvas : Mouse-wheel event filtering/overriding [duplicate]

Possible Duplicate: MouseWheel event filtering on Qgis I’m developing a C++ plugin for Qgis and I want to filter/override the mouse-wheel event. I created a “maptool” to select a polygon ...
5
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2answers
423 views

How to filter the MouseWheel event in a QGIS C++ plugin?

I’m developing a C++ plugin for Qgis and I want to filter/override the mouse-wheel event. I created a “maptool” to select a polygon feature on a vector layer, the feature has two attributes : an id ...
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. ...