An object-oriented programming language

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GDAL Application crashes when loading GDAL drivers

I'm developing on QT an application that uses GDAL library (which I compiled using MinGW 4.8). When I use the application on my windows 8 laptop, it works fine, but when I tried using it on several ...
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1answer
78 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
62 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
48 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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1answer
155 views

QGIS 2.0 Howto copy raster data from a QgsRasterDataProvider to an OpenCV matrix

I'm hacking the half day arround a problem and that I' thought it was simple one. I'm using C++ (QtCreator) QGIS 2.0 und openCV2 on an 64 bit Workstation runnig Debian Wheezy. The Application I try to ...
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1answer
42 views

How do I draw an EllipticArc (or any other Segment) in a Dynamic Layer?

I am trying to draw an EllipticArc (or any other Segment for that matter) in my Dynamic Layer using the ArcObjects C++ API. For something that seems like it should be straightforward, I am having a ...
3
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0answers
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 ...
2
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0answers
60 views

Looking for QGIS 2.4 C++ Hello World example?

In the project I'm working on (C/C++/Qt application), we are trying to integrate QGIS (latest version desirable, 2.4 for the moment). But there is very little information in the web on how to use QGIS ...
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0answers
39 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 ...
2
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0answers
33 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 ...
2
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0answers
380 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 ...
2
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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: ...
2
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0answers
282 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
35 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 ...
1
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0answers
27 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
70 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
23 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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0answers
43 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 ...
1
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0answers
77 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' ...
1
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0answers
57 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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0answers
41 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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0answers
219 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
137 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 ...
1
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0answers
52 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
166 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 ...
1
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0answers
101 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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0answers
172 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 ...
1
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0answers
82 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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0answers
246 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 ...
0
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0answers
8 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, ...
0
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0answers
15 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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0answers
14 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
17 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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0answers
29 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 ...
0
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0answers
18 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 aplicaciĆ³n en C++ que ...
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0answers
53 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
13 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
54 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 ...
0
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0answers
19 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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0answers
86 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 ...
0
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0answers
72 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 ...
0
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0answers
176 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 ...
0
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0answers
191 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 ...
0
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0answers
49 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 ...