An object-oriented programming language

learn more… | top users | synonyms

4
votes
0answers
22 views

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

I have a georeferenced IRasterLayer which is displaying data with no alpha channel. I am trying to specify a color which should be treated as transparent. In ArcMap it is possible to set a specific ...
3
votes
0answers
65 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
82 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
110 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
votes
0answers
43 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
votes
0answers
52 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
196 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
votes
0answers
92 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
votes
0answers
559 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 ...
2
votes
0answers
739 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
votes
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
votes
0answers
386 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
vote
0answers
18 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 ...
1
vote
0answers
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" .... ...
1
vote
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 ...
1
vote
0answers
17 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 ...
1
vote
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 , ...
1
vote
0answers
22 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
vote
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 ...
1
vote
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 * ...
1
vote
0answers
32 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
vote
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 ...
1
vote
0answers
32 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
vote
0answers
21 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
vote
0answers
27 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
vote
0answers
61 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
vote
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
vote
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
vote
0answers
40 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
vote
0answers
124 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
vote
0answers
96 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
vote
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
vote
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
vote
0answers
77 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
vote
0answers
128 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
vote
0answers
94 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
vote
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
vote
0answers
304 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
vote
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
61 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
vote
0answers
236 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
vote
0answers
111 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
vote
0answers
205 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
vote
0answers
105 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
vote
0answers
266 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
30 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++ ...
0
votes
0answers
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 ...
0
votes
0answers
16 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 ...
0
votes
0answers
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 ...
0
votes
0answers
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 ...