An object-oriented programming language

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2answers
587 views

How to show a QGis map in Qt/C++ custom widget with QgsMapCanvas?

I'm trying to add a QGis map in Qt/C++ widget using QgsMapCanvas, but I have some problems... I'm working with the following environment: - Ubuntu 12.04 - QGis 2.8.1 - Qt Creator 2.4.1 (based on Qt ...
2
votes
1answer
1k 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?
2
votes
1answer
114 views

Implement r.cross / ArcGIS Combine with GDAL

I am using GDAL to process a lot of rasters. I then need to combine all the arrays to create a single output raster that represents all the unique combinations of values. I.E the same thing as ...
6
votes
1answer
127 views

Memory Leak when deleting a layer

I am working on a project based on QGIS API c++ 2.8.2 and qt4.8. I have two methods in a class, the first create a layer and add a point Here is the code for the creating: LibCartoError ...
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0answers
20 views

Gdal ogr simplify/intersects

Can anyone give an example: How to use the simplification? For example // read the coordinates of the polygon char * wgsRef = NULL; OGRPolygon *poPol = (OGRPolygon ...
3
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0answers
46 views

GDAL RasterIO performance in C++ vs ReadAsArray in python/numpy

I'm currently writing optimisations for a raster viewer program which uses gdal as it's base. It's currently written purely in python, and has some major speed issues which cause problems when we are ...
1
vote
1answer
10 views

InitSpatialMetaData errors with Spatialite

This Stackexchange may not be the best place for this question but I will start here. I am trying to create a spatially-enabled, sqlite3 database. The following code is a short example of what I am ...
1
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1answer
271 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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2answers
322 views

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 ...
1
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1answer
205 views

Run C++ standalone application in debug mode

I write simple C++ standalone application using QGIS. It works and render vector layers from PostgeSQL database. #define CORE_EXPORT __declspec(dllimport) #define GUI_EXPORT __declspec(dllimport) ...
0
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1answer
241 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? ...
0
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1answer
50 views

Seeking C++ api to read/write PostGIS?

I need read/write geometry object from PostGIS. Is there C++ library to do this?
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0answers
18 views

Read GeoTiff from memory in GDAL

Is it possible with the GDAL library to read an image (e.g. GeoTiff) from a memory stream, like stdin instead of a defined location on the local disk? It would be useful to read data in streaming ...
0
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0answers
9 views

Get projection/datum from GeoTIFF in C/C++

I am trying to create a GeoTiff importer for an application I'm developing, but for now I am kind of lost. I am using libgeotiff in C/C++, and for now, what I have done is projection points using ...
2
votes
2answers
599 views

How to convert latitude, longitude to EPSG 3857?

I'm looking to study the math involved to see how a given latitude and longitude in decimal degrees can be converted to epsg 3857. Can anybody point to a good reference or a possible python/c/c++/java ...
1
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0answers
58 views

Qgis C++ hello world example

i am new in developpement with C++, i try to realise an application with C++ which can read and display a *.qgs file from Qgis, i tried the code bellow but it doesn't work, it always show me errors ...
2
votes
1answer
26 views

QGIS CPP multi-platform plugin deployment

We're starting to look at porting some of our plugins over from ArcMap to QGIS and we're pretty excited about it. Currently everything we have is written in C++ so it would be nice to use that on ...
3
votes
1answer
1k 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 ...
3
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0answers
31 views

ArcGIS Server Object Extensions: how do I deploy extra .dll's?

I am developing an ArcGIS Server Object Extensions in C# that makes calls into a C++ .dll. How do I add this .dll to deployment? By that I mean that I want it included in the .soe.
3
votes
1answer
40 views

Reading 1/3 arcsecond DEM data using C++?

I am writing my own application to use and present elevation data. So far, I've been easily using the three arc second SRTM data presented in ArcInfo ASCII format. But now I'm looking to use the ...
5
votes
2answers
93 views

Why am I getting two different outputs from Python and C++ using GDAL?

I am trying to gather information from a *.tif file using the GDAL libraries. When I open the *.tif file using both the Python API, and C++ API, I encouter two completely different answers. Here are ...
4
votes
0answers
20 views

Is there a way to use the GDAL C++ API to find areas of overlap between two SAR images?

I have a bunch of SAR images (about 1 GB each) on which i need to do some image processing. Each image is georeferenced and there is significant overlap between each pair of images in the set ie. one ...
1
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4answers
610 views

How to crop Geotiff image in C++ (GDAL or other possibilities)?

I am developing a code to process a geotiff image. But firsly I need to crop a geotiff image preserving its metadata (projection...) in C++. My idea it's to provide the corners and the geotiff image ...
2
votes
1answer
2k 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 ...
3
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1answer
189 views

Build ESRI addin with C++

Is it possible to build an ESRI addin (.esriaddin) using C++? I see templates for .NET and C# only but perhaps there is a manual method?
0
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0answers
16 views

Using SpatiaLite with Clion

What is the easiest way of importing the SpatiaLite (C++) with the Clion IDE ? I have been trying all sorts of different ways, but nothing seems to work. Does anyone know how ?
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0answers
17 views

How can Qt viewer be opened from ArcGIS?

I have a standalone Qt viewer. I want to open Qt viewer from ArcGIS when user clicks on any point in a point shapefile and Qt viewer shows the data from attribute table of that shapefile.
2
votes
1answer
220 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 ): ...
0
votes
3answers
576 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 ...
25
votes
10answers
10k views

How do I develop my GIS programming skills?

I would like to develop my GIS programming skills, where do I start? People say learn C++ or Python but where can I learn this in a geographic context? Tutorials or anything would be very helpful, as ...
3
votes
1answer
268 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?
1
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0answers
151 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
17 views

how to draw curved line in a qgsmapcanvas

i am working on a project with qt4.8.6, api c++ of qgis 2.8.2 we need to draw curved line in a vectorlayer by given 2 points and an offset by exemple is it possible to do that with the c++ api of ...
1
vote
1answer
26 views

Changing Dataset Property

I 'm working on GDAL C++. But I have some trouble to change GDALDataset property. I have converted "jpg" to "bmp" an image. But I want to do read an image(jpg) to gdaldataset then change dataset ...
1
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1answer
16 views

pinchZoom with qgis 2.82 and qt

I am working with qgis 2.8.2 c++ api and qt4.8.5 in my project i had to implement the pinchzoom because i use a 27" touch screen i am looking for information on how to use the qgis lib with the qt ...
1
vote
1answer
32 views

raster doesn't redraw to fit the canvas after a zoom in and a pan

i am working with qgis 2.8.2, c++ api and qt 4.8.5 i have a layer in the mapcanvas, this layer contains a raster ( a georef tif picture ) when i zoom in, the raster fill the entire canvas , ok but if ...
1
vote
1answer
15 views

problem with qgsmaptoolpan

i am using the c++ api qgis 2.8.2 i have a strange problem when i want to use the pantool for my canvas i used this code : mpPanTool = new QgsMapToolPan((QgsMapCanvas*)mpMapCanvas); ...
1
vote
4answers
153 views

OSM tiles offline display using c++

I have openstreetmap tiles for offline (png images), how can I display these images (tiles) on my application with zooming and rotation functionality as on openstreetmap.org using c++?
3
votes
2answers
44 views

Converting Python GDALDataset to C++ GDALDataset

I'm currently writing a C++ extension to python to speed up a raster data viewer which is running extremely slowly with our large datasets. I've managed to get a small speedup by writing a C++ ...
0
votes
0answers
8 views

OSM map tiles offline view [duplicate]

How can I view openstreetmap tiles offline using c++? I need to integrate osm tiles viewer (view tiles, zoom etc.) offline on c++.
2
votes
1answer
53 views

Fastest way to process OSM

I've been working with imposm and Python, it's fairly easy to parallelise. I've hit a performance problem when trying to associate the coordinates to the ways. Creating a dictionary from ...
0
votes
0answers
182 views

GDAL in C++: Resize Image (gdal_warp?)

I would like to resize a geotiff using GDAL in C++. Searching online, I bumped into another question here that explains it is possible through gdal_warp and gdal_translate via terminal. But there ...
1
vote
3answers
610 views

Convert .tiff data to bitmap just when rendering and at runtime by visualC++ code

I need to convert a .tiff image to a bitmap one without saving the bitmap. I know that I should use GDAL_translate but because I'm new, this function's interface is a little complicated for me. Could ...
1
vote
0answers
70 views

Using GDAL in C++. Create multiple GDALDatasets using a GDALDriver produces error 4 not recognised as a supported file format [closed]

I am trying to create multiple GDALDataset objects. All of them are supposed to be in the .tif format, so for all of them I use the same GDALDriver. I am working in C++ (Visual Studio) and when I ...
3
votes
1answer
24 views

Help with Meters at Lat calculation accuracy, two methods

So I'm coding a program (c++), and thing leads to thing, and I need to find out how many meters to a degree of longitude at a specific latitude to a very high precision. Optimally < 1 meter at all ...
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1answer
1k views

Sample for MS Visual Studio C++ using GDAL library

I need to create a sample console application on c++ that will use *.hdf file as an input and will read it. As I got, I need a GDAL library. I've found a GDAL tutorial on official GDAL website, but ...
1
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1answer
35 views

QGIS not opening after update

I installed/updated microsoft visual c++ 2013 and microsoft directX runtime 2013. After that, whenever i open qgis i get this The program can't start because MSVCP120.dll is missing from your ...
3
votes
1answer
131 views

Extracting values from raster under line using GDAL?

How can I find the cells which lie on a straight line between two points? I.e. how can I find the indices of the cells (in grey) which are intersected by the line defined by the two points (in blue): ...
0
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0answers
48 views

I want to make a small TIFF file from a big TIFF file

I just study on GIS system. When I create the Tiff file, there is no any data in Tiff file I want to make 4 channel TIFF file My code is below: void crop(const char *inputPath, const char ...
1
vote
1answer
87 views

GDAL/OGR in C++: Merge multiple vector datasets to single [closed]

I need to merge multiple kml files into a single one. I found that I could use "ogr2ogr -append" but I have to do it through c++ and my Google-fu hasn't been successful so far. So, any ideas? Also, ...