An object-oriented programming language

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How to load a *.qgs file in a C++ QGIS standalone app?

I'm using QGIS-2.4.0 API to develop a standalone app by C++. I saved a test.qgs file in QGIS Desktop software, in the project, there was one layer and it was visible. Then I loaded the test.qgs ...
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1answer
85 views

OGRFeature::DestroyFeature fails

I am using OGR to read features from a shape file; when the feature is destroyed I am getting an error 0xC0000005: Access violation reading location 0xffffffffffffffff. This secton of the code looks ...
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1answer
68 views

Calculate tree cover over certain area from raster data

Last year Hansen et al. published Global Forest Change map as set of raster data available in TIFF format. Basically those are 30-meters resolution satellite images with pixel values ranging from 0 ...
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1answer
63 views

gdal_contour transparent contour as png

I started using the GDAL Library in a c++ project. It is a great library, but I am a bit stuck right now with different aspects of it. What is the best way to use gdal_contour in my c++ programm? ...
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57 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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0answers
37 views

What is the issue with geopdf format?

I'd like to add the geopdf format as output of a library that I am working on. After have looking around, I have not been able to find a (c, c++, python) library that meet my license requirements ...
2
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0answers
52 views

How to develop a real-time navigation App using QGIS API?

I want to develop a navigation application based on QGIS using C++, for live tracking. I think it is quite normal for GIS to do such things, especially QGIS as it is a very mature GIS platform. But ...
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44 views

How do you clip a gnomonic or stereographic azimuthal projection?

I have polygons comprised of lat/lon coordinates and I want to project them onto a plane that's appropriate for polygon operations (such as checking for intersections). In some cases, the polygons ...
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409 views

Completely new to GDAL: please help me with the best way to study it

This is the first time that I post here so pardon me for asking such a beginner question. I'm completely new to GDAL and I'm going to use it to work with satellite images, DEMs, etc. I have some ...
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0answers
56 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: ...
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0answers
297 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.
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11 views

Point Symbolizer() in rundemo.cpp file Giving error

The code is given Below: roads2_rule_11.append(point_symbolizer("abc.png")); The error is given below: rundemo.cpp: In function âint main(int, char**)â: rundemo.cpp:142:57: error: no matching ...
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0answers
20 views

What is a Format of csv plugin datasource string in mapnik

I have tried that Format Is that is a correct format to pass to CSV plugin,the sample C++ code is given Below: std::string csv_string("wkt,Name POLYGON((5.123456 51.6, 6.8 52.6, 7.8 51.6, 5.123456 ...
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0answers
46 views

How to create a svg item onto Map Canvas in QGIS API?

I'm working on a project with QGIS-2.4.0 API using C++. I need to load some svg files to the application for displaying as symbols. QGIS API has a class named QgsMapCanvasItem, which is an abstract ...
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33 views

Rendering a geotiff block with gdal and gdk-pixbuf - Some flaws in the result

I currently try to render a geotiff file with GTKmm\GDKmm (gdk-pixbuf). The file is a tiled geotiff with a block size of 256*256 and three rasterbands. The shortened gdalinfo output is: Driver: ...
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0answers
95 views

Correct way to extract pixel data using GDAL. Current method gives repeated but changing value.

I am trying to open a spectral file and move bands of data from GDAL to OpenCV's Mat data structures. As of now I am just trying to make sure that I can correctly access each band using GDAL and pull ...
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0answers
25 views

C++ parser for OGC Filter Encoding 1.0

I'm developing a C++ application and I have to parse a OGC Filter in order to implement querying functionality on a metadata repository. Does anyone know any C++ library to parse OGC Filters? Thanks. ...
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47 views

How to rasterize a vector data with style

I want to make a utility in c++ which can rasterize vector data with some specified style. I know about gdal_rasterize. But the problem with it is, we cannot specify the style details. Do we have a ...
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0answers
83 views

GDAL C/C++ API and filtered pyramid tile generation

I have been tasked with adding functionality to an existing C++ developed toolset whereby a source dataset (typically a single GeoTIFF) needs to be split into tiles at various resolutions ('zoom' ...
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0answers
62 views

Icon missing when adding custom combobox command to Toolbar

I have a custom command: class ATL_NO_VTABLE CSliceSelector : public CComObjectRootEx<CComSingleThreadModel>, public CComCoClass<CSliceSelector, &CLSID_SliceSelector>, ...
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43 views

start gdalbuildvrt from c++ plugin

I want to create a vrt from my plugin via gdal-tool. From OSGEO4W-Shell the command works. In my code i tried this: QString program = "gdalbuildvrt"; QStringList arguments; ...
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246 views

ArcGIS (ArcObjects) Windows 7 - 64 bit -support

I have been developing with ArcGIS Cross Platform C++ SDK (with Qt 4.8.2) on 32 bit Windows XP SP3 (development machine). I used to use MapTool Control within ArcObjects on the development machine. ...
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0answers
147 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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0answers
54 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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0answers
171 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 ...
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104 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 ...
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0answers
177 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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0answers
87 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; ...
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248 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 ...
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11 views

What is the input format to the M-GEMMA map matching tool?

I am researching different map matching algorithms. Based on the Map Matching StackExchange discussion I came across the M-GEMMA tool written in C++, which can be downloaded here. A literature discuss ...
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12 views

postgis & mapnik “column ”CLASS“ does not exist”

I've piped an osm map of greece into postgis with osm2pgsql and was playing around with C++ mapnik sample code giving "planet_osm_polygon" as the source table: parameters p0; p0["type"] = ...
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18 views

Adding Raster Layer in C++ application always result in layer invalid

I am trying to add a raster layer in c++ application with QtCreator and QGIS 2.6.0. My code is as follows: QgsRasterLayer * layer = new ...
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34 views

Syntax Error in qgsapplication file

I am trying to test an QGIS application code example. However, when I try to compile it, it is reporting errors in qgsapplication.h which is coming with the source code of QGIS. I am using QTCreator ...
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0answers
11 views

How I use point symbolizer for styling in mapnik c++ source code?

I have tried point symbolizer for styling in c++ mapnik source code ,the given code line : roads2_rule_11.append(point_symbolizer("/home/razaliaqat/raza.jpg")); But it is giving an error given ...
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11 views

Pass Data as a String Using Mapnik CVS Plugin

I am new in mapnik and c++ I need Help. I have a code written in C++ that read a data using postGis .The Sample Code is given Below: parameters p; p["type"]="postgis"; ...
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49 views

Open a *.qgs project file in API, why maps do not show?

I'm using QGIS-2.4.0 API. I saved a test.qgs file in QGIS Desktop, in this project, there is one layer that is visible in it. Then I open the test.qgs project file in QGIS API to developing an App, ...
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0answers
21 views

How To Add a QgsSvgMarkerSymbolLayerV2 to VectorLayer in Qgis?

I'm using Qgis2.4.0 API to develop a C++ application. I want to add a svg symbol to a vector layer. Here is what I have already done: add vector, then add symbol. But I get stuck dong this. Here is my ...
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16 views

change symbology of an graduated renderer in qgis

In my plugin(c++) I add a vectorlayer to map, then I change the symbology of the QgsGraduatedSymbolRendererV2 of this layer. After this I refresh the map with ...
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0answers
19 views

Write to FGDB in C++ code?

Anyone know the correct syntax for this? I'm a C++ beginner but experienced in GIS.. I'm guessing ofstream won't do it and am not sure what else to try. Never written to any sort of database in C++.
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34 views

compile QGIS-plugin for Windows: problem with gdal_i.lib version

While compiling my plugin for QGIS 2.2 there are no errors, but it ist still not loading in QGIS because of an dll error. (function not found) I think the problem is at the gdal version. The ...
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24 views

Parsing OGC Filters with C++

Google Translation I am developing an application in C + + you need to parse OGC filter. Anyone know any way to parse an OGC filter with C + +? Estoy desarrollando una aplicación en C++ que ...
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0answers
56 views

gdal read whole geotif band into vector

i have another c++ GDAL question. I try to read alle elevation data out of an GeoTiff file into a c++ vector so that i can get elevation at x,y like this: vector[x][y]. I also like to use this data to ...
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0answers
14 views

ArcObjects: how do I resize an IComboBox when the contents changes?

In ArcScene: I have implemented an IComboBox where the content changes: void MyComboBox::updateComboBox() { std::vector<CComBSTR> comboBoxItems; getComboBoxItems(comboBoxItems); long ...
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0answers
57 views

ArcObjects: How to remove a custom layer?

How is a custom layer supposed to be destructed? I have a custom layer that implements drawing by overriding IActiveViewEvents::AfterDraw. The problem is that sometimes when the custom layer is ...
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0answers
21 views

How to define own icon for qgsvertexmarker?

I want to use a small image instead of predefined icons of vertex marker in qgis. how to do this? QgsVertexMarker * marker = new QgsVertexMarker(mPlugin->iface()->mapCanvas()); ...
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90 views

Using GDAL to link to a TMS

I currently have a C++ application that will consume a WFS using gdal. It determines if the WFS layer is points or polygons then adds stores them in an appropriate object that is later used to ...
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0answers
79 views

Unable to view a wms layer in QGIS cpp aplication

I am a newbie in QGIS c++ programming, and I am trying to load a raster file from a WMS and display it. The image I want to display can be obtained from this url ...
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0answers
181 views

QGis 2.0.1 cpp-plugin for Windows

my plugin, developed in VS2008 for Windows runs in my testenvironment, the startimage of QGIS shows the developermeeting in Essen with the version number 2.1 alpha. On a other system I have installed ...
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213 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 ...
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51 views

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 ...