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3
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0answers
59 views

GDALRasterizeGeometries doesn't burn correct Values

What I have is a vector shape file with a string field. What I've done is written a CSV file with the field ID, field_value and now I would like to rasterize the vector layer as a byte raster with the ...
3
votes
0answers
77 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
votes
0answers
108 views

Microsoft Visual C ++ Crash when Install qgis.2.8.1

I have installed and reinstall QGIS ver.2.8.1. and always display a message as shown below. I hope someone can help me fix these problems. Thanks for your help.
2
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0answers
40 views

In version 2.4 vector layers with labeling switch off caching

I am developing a map display stand alone application using the C++ API. With version 2.6 the caching mechanism is ignored for vector layers with labels. The reason is to avoid conflicting labels. ...
2
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0answers
48 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
votes
0answers
176 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
88 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
686 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
58 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
373 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
24 views

How to render the Sea depth level in different color?

I would Like to adapt an old code in c++ using the api qgis 1.6 : const QgsRenderer* lrenderer = pLayer->renderer(); if( lrenderer == NULL ) lrenderer = new QgsSingleSymbolRenderer( ...
1
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17 views

Non-Square Pixel on georeferencing of images using GDAL

I have a image in .jpg format. I have some GCP and also know the pixels values of these GCp in that image. Now i trying to convert this image into geotiff. for that I have coded the following lines. ...
1
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32 views

Run C++ DLL in ArcMap 10.3

I've migrated a VB script that uses ArcObjects to a C++ Win32 DLL (using Visual Studio 2013). And now I would like to test my DLL by launching it from my ArcMap 10.3 installation. The problem is that ...
1
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0answers
13 views

How to fill a symbolLayer with a custom texture?

I have this code : pLayer is a QgsVectorLayer * QgsFeatureRendererV2 * lrenderer = pLayer->rendererV2(); QList<QgsSymbolV2 *> lSymbols = lrenderer->symbols(); QgsSymbolLayerV2 * ...
1
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0answers
23 views

C++ Convert Lat Long to BNG with Proj.4

Im creating a plugin for VBS2. In the program I can output a grid in either LAT LONG,UTM or MGRS. I need to be able to convert to BNG. I have managed to create a TKinter application in python that ...
1
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0answers
10 views

where are old function of qgssymbol

in the new version of qgis 2.8, in the c++ API and in the class QgsSymbolV2, a lot of function has been deleted, by exemple setfillcolor, setcustomtexture, setnamedpoint, setpointsize i would like to ...
1
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0answers
26 views

C++ QGIS Conditional Label Colouring

I am using QGIS and C++. When I create a layer of polygons with labels in the center I am able to use a RuleBasedRenderer to control the background colour of the polygon. How do I similarly control ...
1
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0answers
18 views

C++ Get Capabilities from a WFS

To start off with: Coding in C++ Using the QT Creator Reading from WFS Version 1.1.0 Using Gdal/OGR compiled with Xerces Hi all so I'm trying to get all of the Capabilities from a WFS. I know how ...
1
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0answers
22 views

QgsSpatialIndex crash my deploy C++ QGIS custom application on windows

When I use the QgsSpatialIndex class, after leaving the method, my application crash. Looks like the object QgsSpatialIndex class works, it brings QgsFeatureId list, but from what I noticed something ...
1
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0answers
54 views

How do I step into the C++ functions from an external Python app I'm debugging?

I just wanted to see how to step into the C++ class QgsVectorLayer()'s methods from the python call to QgsVectorLayer(self.uri.uri(),'foo','postgres'). I'm trying to debug and it trying to step into ...
1
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0answers
17 views

Getting incorrect results for Geary's Coefficient algorithm (incorrect math?)

I'm not sure if anyone here can help me with this, but I'm currently working on a program that uses a spatial autocorrelation algorithm to analyze patterns in an image. It's supposed to return values ...
1
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0answers
22 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 ...
1
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0answers
34 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 ...
1
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0answers
117 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
90 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: ...
1
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0answers
478 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 ...
1
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0answers
22 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 ...
1
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0answers
39 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. ...
1
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0answers
74 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
121 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
92 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>, ...
1
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0answers
48 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; ...
1
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0answers
300 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. ...
1
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0answers
201 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
vote
0answers
59 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 = ...
1
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0answers
227 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
110 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
199 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
102 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
265 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
votes
0answers
6 views

Problem with the DSID Data Set Identification

In my s57 file, I need to set the extent of the mapcanvas, for that i use : mpMapCanvas->setExtent(mpS57->mMapplay.value(DSID)->extent()); but if I display the value of the extents xmin, ...
0
votes
0answers
11 views

help for rendering s57 file

I am working on a specific project based on QT 4.5 and QGis API C++ 2.8.2 I have a S57 File, I want to load it, and render it into a canvas My canvas is created, the build and link is ok,no error, ...
0
votes
0answers
11 views

how can i change property of a symbol using qgis 2.8 c++ api

i have an application written in QT 4.6, and use the C++ API of QGIS the application will display the data of the s57 file in a MapCanvas i managed to read the file but how can i , for a specific ...
0
votes
0answers
15 views

OGRFeature set Multiple fields

Hi all to start off with: Using Gdal compiled with Xerces Coding in C++ with the QT Creator version 5.4.1 So my problem is im trying to use Gdal to create my own Esri shapefile, I get a strange ...
0
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0answers
35 views

Is there an open source solution to access raster layers in an ESRI File-GeoDatabase?

I'm looking for a way to access raster layers in an Esri File-GeoDatabase without using ArcObjects or ArcPy, specifically I would like to access the raster layers with GDAL. I understand that the GDAL ...
0
votes
0answers
46 views

How to remove a QgsMapCanvasLayer from QgsMapCanvas with PyQGIS || C++?

I try to find a way to remove a QgsMapCanvasLayer from the QgsMapCanvas. At the moment I only can delete the MapLayer from the QgsMapLayerRegistry with: ...
0
votes
0answers
55 views

GDAL, Georeferencing

I have been trying to use GDAL library to add geoinformation to an image. From the documentation from GDAL web page I could find that I could use GDAlSetGeotransform(), for that I need a six ...
0
votes
0answers
14 views

qgis (WIN): change settings from registry to INI

I have built qgis on windows 7, and need to stop the settings from being written to the registry. Is there a way to have an ini file created and used instead? (Having trouble finding that code)
0
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0answers
37 views

Using GDAL with a line layer and points layer, find next point along line layer

With the points layer and line layer, I'm trying to create a graph for path finding. I've got a line layer that I've dissolved, thinking that might make this easier. The points in the points layer lie ...
0
votes
0answers
38 views

Select feature within radius

I am developing a plugin (C++) and somehow I am stuck (I am very new to this). I start the plugin which has an own gui. There is a button to select features from the vector layer. Clicked on it, the ...