An object-oriented programming language

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Problem creating polygon in a layer

I am working in c++ qt4.8.5 and api qgis 2.8.2 c++. In my application I had to put polygon to define attractive zone. I found a great post in stackexchange (86812). I have based my on this post and on ...
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1answer
18 views

How to create a specific svg file with data from a feature

I am working in c++/ QT4.8.5, with qgis api c++ 2.8.2 I have to display a dynamic icon for a feature. some of the data change periodically and in order to display the change i need a svg that can get ...
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2answers
37 views

is it possible programmatically to rotate a svg of the feature without rotate all feature

I am working on a project that need to move and update the shape of the feature of the layer. I am working in c++/ QT4.8.5 and qgis api c++ 2.8.2. In my Layer I have a lot of features, each feature ...
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1answer
45 views

C++ code and ArcGIS Button

I have some code in c++ that used gdal and process raster and create an output raster. I want to create a button in ArcGIS Desktop (using ArcObjects SDK 10.2 c#) and pass the raster layer to my c++ ...
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1answer
52 views

Is it possible to change the geometry without startEditing the layer

I am working in c++/QT 4.5 with the QGis 2.8.2 API. I had to change the geometry of features in a layer each second. Each second new data comes from the Ethernet connection, the application gets the ...
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2answers
45 views

IRasterLayer background transparency in C++ with ArcObjects 10.x .NET

I have a georeferenced IRasterLayer which is displaying data from a PPM file with no alpha channel. I am trying to specify a color which should be treated as transparent. In ArcMap it is possible to ...
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2answers
133 views

Free 3rd party library for showing geospatial vector information

Up to now, I have used GDAL to extract raster data from geotiffs and then, OpenGL to show that raster data. But when it comes to extract vector data with the help of OGR, what library would you ...
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1answer
13 views

How to add a point in a empty vetorLayer creadted in memory

I am working in c++/qt 4.5 and qgis api c++ 2.8.2 I had to create and empty vectorLayer and add Point I saw in the qgis cookbook that it is possible to create a vector layer in memory ,I did that, and ...
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19 views

How to change programmatically the value of attribute in one of several feature in a vectorLayer

I have a vectorlayer that contains a lot of feature, I know that each feature has an unique Id Each of them has some propertie like coordinateX, coordinateY, color, name With a QTimer, each 2 sec I ...
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1answer
11 views

Building error on changegeometryvalues

I am working with c++/QT and c++api gqis 2.8.2 I want to change the geometry of a feature, I have this code : QgsVectorLayer * lLayer = mMapLayer.value(TRACKS); QgsVectorDataProvider * ...
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14 views

how to rotate a symbol

I am working in c++/python/QT 4.5 with the api qgis 2.8.2 My application receive data from a communication port that indicate the change of position of an object diplayed on the map and represented ...
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13 views

How to change the value tof the use tag in a svg file

I am working in C++/QT4.5 with the qgis c++ api 2.8.2 I have a svg file that contains different form tag by Id When i want the first form i place the id name in the use xlink:href="#formname" .... ...
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1answer
14 views

How can i catch clicked signal on a qgsmapcanvas

I am working under c++ with the qgis API 2.8 In order to make different operation on a canvas like personnalized rotation or selecting a region for zooming, I had to catch different signal like ...
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0answers
18 views

Showing an Overview map with the ArcGIS C++ QT Runtime

I am using the Esri ArcGIS QT API for C++ and trying to create an overview map for my application as found here: Multiple maps - https://developers.arcgis.com/qt/cpp/guide/multiple-maps.htm I am ...
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0answers
12 views

How to SetVisible a layer without redraw all the mapcanvas

I am working with QGis 2.8.2 API c++/ QT 4.5 I am displaying a lot of layer in a mapcanvas, I am looking for a method like setVisible(boolean ) in order to setvisible or not a specify layer ...
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2answers
2k 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 ...
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1answer
24 views

Convert Shapefiles into Raster — C++

I'm coding an algorithm which uses as an input a map from QGIS. The software has been implemented in C++ and my idea is to convert, automatically, a shapefile into a raster one. Is there any function ...
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2answers
195 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 ...
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0answers
18 views

VectoreLayer Still Empty even if attribute has been set with value

I am working with the qgis api c++ 2.8.2, my application is written in QT 4.5.3 / C++ I had to create a vectorlayer in memory with attributes and features and export it to a shp file to import it in ...
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13 views

Problem with VectorLayer created in memory

I am working in c++/QT whithnthe qgis API c++ I had to build a personnalized vectorlayout called "TRACKS" , so i write a function that create in memory the vectorlayer like this : QgsVectorLayer ...
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2answers
18 views

Building error with QgsVectorFileWriter

I am working with qgis api c++ 2.8.2, in c++/QT 4.5 I try to save my List of QgsField but I have the error message : no matching for call to 'QgsVectorFileWriter' I took the sample from here : ...
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13 views

List of default attribute of a feature?

I am working with c++/!qt with the c++ api qgis 2.8.2 for a stand alone project application I had to change and add attribute for feature Does anyone know where i can find the default attribute of a ...
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16 views

Need help on how to move a symbol over a map

I'm working in c++/qt and the c++ api qgis 2.8.2 In my application i load a map with a s57 file, this part works perfectly, now i need to make some plot representing different object like boat, plane, ...
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5 views

SegFault on create an EmptyDataSource From a typedef

I had to create a specific type of point, in order to do that I create a function that create a layer from shp file and data extract of the Code : typedef bool ( *createEmptyDataSourceProc ) ...
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1answer
52 views

Georeferencing las files using liblas

I am trying to write georeferencing information to a '.las' file using liblas and c++. Here is my code: ofstream ofs; ofs.open("test.las", ios::out | ios::binary); liblas::Header header; ...
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2answers
75 views

How to create a dashed polygon border in C++?

In my maps I have a symbol, his type is polygon, I want to change the line style of the border, actually is solid , I had to put it in dash Is there a simple way to change it ? i think to the ...
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1answer
149 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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12 views

How can I extract the latitude and longitude from a s57 File [duplicate]

I had to extract the longitude and latitude from a s57 file, in order to superpose a satelite view from the same point. These coordinate will allow me to get the exact position on google map by ...
1
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1answer
31 views

Rendering of SVG for layer symbols using QGIS?

I have a little problem with the rendering of SVG for layer symbol. I want to creeate a categorized symbol to show different style of buoy I have for that two icons the first is an half circle ...
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25 views

Problem using EPSG:3395

in my application I use OGC:CRS83 for the coordinatereferencesystem, but now I had to change it to EPSG:3395 when I call : mQgsCoordinate->createFromOgcWmsCrs("EPSG:3395") there is nothing in ...
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1answer
32 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( ...
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Problem on rendering categorizedSymbolRendererV2

Finally my code works but the renderering display just one color instead of 4 I don't know why, I follow the sample code of the snorf.net website and the sample code in the qgis python programming ...
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0answers
11 views

How can I inject categorizedSymbolRenderer into My QgsFeatureRenderer?

I try to get the categorizedSymbolRenderer value in order to render them In all sample of code I found ( in python but not in c++ ) it said : renderer = QgsCategorizedSymbolRendererV2(expression , ...
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9 views

Why I have a SegFault on a newSymbol->setColor?

I am working in C++ and QT, I have to write an application based on the qgis c++ api 2.8.2. So, I try to do the same thing that the sample code in python on the webSite ...
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1answer
26 views

Information about the setDataDefinedProperty

In the QGis C++ API v1.6 there is a function called setlowerValue to set a value for a specific Symbol In my application i use QGis C++ API 2.8.2, i try to understand how the function ...
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0answers
41 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 ...
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8 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, ...
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1answer
26 views

Problem with QgsCoordinateReferenceSystem

I would like to change the coordinatereferencesystem for my application I have this code : QgsMapRenderer* myRender = mapRenderer(); mQgsCoordinate = new ...
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0answers
23 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. ...
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28 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, ...
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1answer
26 views

looking for documentation about exploiiting OSM file with c++ API

My application is written in QT4.6, i use the C++ API of QGIS 2.8.2 i had to read and display OpenStreetMap in my canvas in my application so, i am looking for some documentation or tutorial for ...
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0answers
14 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 * ...
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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 ...
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36 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 ...
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1answer
27 views

GDAL Truncating/Normalizing Field names

While creating a ESRI-Shapefile using GDAL, it keeps truncating/normalizing my field names. Any reason why it does this? If the Field name is more than 10 characters it seems to do this. For example ...
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1answer
24 views

Error during building an application c++ using api qgis 2.8

I have an apllication that need an object the object type is QgsSymbolV2 but i cannot do that : QgsSymbolV2 * lSymbol = new QgsSymbolV2(); because in the class qgssymbolv2 there is no constructor ...
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0answers
12 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 ...
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17 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 ...
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1answer
39 views

Convert Polygons,Points,Lines to GML

I've got a vector of Points, Polygons, Lines. And I'm trying to convert the points into a GML file like a Web Feature Service. I've been doing some reading but cant find any methods that can do this? ...
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1answer
134 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 ...