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4
votes
2answers
166 views

Is there a GIS-Tool that fit my needs?

I´m working on a GIS-Project in the Defense & Intelligence sector. The goal was to develop/create a GIS-Service that: stores and manage GIS-Data (Map data, Height data.. ) has a repository for ...
1
vote
0answers
10 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 ...
2
votes
0answers
18 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. ...
1
vote
1answer
43 views

How to develop c++ standalone QGIS C++ Application

I want to integrate QGIS in QT\C++ application. I try to write basic C++ apllication to render map and build it using MSVC 2010. class PostGisViewer: public QMainWindow { public: PostGisViewer(): ...
0
votes
1answer
29 views

Generate delaunay triangulation from 3D(x,y,z) points

I have 3D Points array.each 3D point have x,y,z data. I want to generate delaunay triangulation.I am new in delaunay triangulation. My array as below. -256.24 85.35 5.0 -262.24 84.35 15.0 -263.24 ...
0
votes
0answers
11 views

What is the input format to the M-GEMMA map matching tool?

I am researching different map matching algorithms. Based on the Map Matching StackExchange discussion I came across the M-GEMMA tool written in C++, which can be downloaded here. A literature discuss ...
0
votes
0answers
15 views

postgis & mapnik “column ”CLASS“ does not exist”

I've piped an osm map of greece into postgis with osm2pgsql and was playing around with C++ mapnik sample code giving "planet_osm_polygon" as the source table: parameters p0; p0["type"] = ...
0
votes
0answers
22 views

Adding Raster Layer in C++ application always result in layer invalid

I am trying to add a raster layer in c++ application with QtCreator and QGIS 2.6.0. My code is as follows: QgsRasterLayer * layer = new ...
1
vote
0answers
15 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
23 views

when make a cross-platform c++ GIS core, how to make the 2d-drawing platform independent? [closed]

i try to develop a c++ no-GUI GIS core(i want the core have no GUI related things, do not use any GUI library) and I can figure out how to do other things except the drawing part. when cope with 2D ...
2
votes
0answers
40 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 ...
0
votes
0answers
36 views

Syntax Error in qgsapplication file

I am trying to test an QGIS application code example. However, when I try to compile it, it is reporting errors in qgsapplication.h which is coming with the source code of QGIS. I am using QTCreator ...
1
vote
1answer
69 views

How to load a *.qgs file in a C++ QGIS standalone app?

I'm using QGIS-2.4.0 API to develop a standalone app by C++. I saved a test.qgs file in QGIS Desktop software, in the project, there was one layer and it was visible. Then I loaded the test.qgs ...
0
votes
1answer
15 views

What is a purpose of parameter 'separater' in mapnik csv plugin datasource?

What is the purpose of the parameter 'separater' in the Mapnik CSV plugin DataSource Example of the code: parameters p; p["type"]="csv"; p["inline"]=quotedStr; ...
0
votes
0answers
12 views

How I use point symbolizer for styling in mapnik c++ source code?

I have tried point symbolizer for styling in c++ mapnik source code ,the given code line : roads2_rule_11.append(point_symbolizer("/home/razaliaqat/raza.jpg")); But it is giving an error given ...
1
vote
0answers
20 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 ...
0
votes
0answers
14 views

Pass Data as a String Using Mapnik CVS Plugin

I am new in mapnik and c++ I need Help. I have a code written in C++ that read a data using postGis .The Sample Code is given Below: parameters p; p["type"]="postgis"; ...
0
votes
0answers
57 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, ...
2
votes
1answer
54 views

How to write a custom canvas item for SVG marker by subclassing QgsMapCanvasItem in QGIS?

I want to subclass QgsMapCanvasItem for SVG marker in QGIS, I looked up a similar topic in stackexchange and QGIS mailing list, I found that this is similar to mine, I did exactly what @Nathan W did. ...
2
votes
1answer
218 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 ...
2
votes
1answer
100 views

Add band to GDAL VRT dataset and convert to TIFF

I'm trying to add a band to a TIFF dataset by converting it to a VRT format and using the AddBand() function, then convert it back to a TIFF to access the band and write the data. Here is an example ...
2
votes
0answers
61 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 ...
1
vote
0answers
53 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
2answers
75 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 ...
2
votes
2answers
97 views

Error getting ESRI Shapefile driver OGR in C++

I am unable to create an OGR Layer using the C++ API. I have followed the documentation at this link exactly http://www.gdal.org/ogr_apitut.html I get an error trying to get the shapefile driver. Any ...
0
votes
1answer
50 views

going from hillshade to percent shaded (gdaldem)

I assumed hillshades output percent shaded (scaled to 255) at the given azimuth and altitude but this is incorrect. A flat raster at 80 degrees altitude has a maximum value of 251 instead of 255. How ...
2
votes
0answers
49 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 ...
0
votes
0answers
27 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 ...
1
vote
2answers
93 views

Does QGIS support dynamic display?

I'm a new developer of QGIS using C++. I am working on a project which needs to display dynamic maps/layers(just like GPS, but it is not GPS, however it should display data alike GPS data - dynamic ...
1
vote
0answers
40 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
115 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 ...
0
votes
0answers
16 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 ...
0
votes
0answers
20 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++.
0
votes
0answers
35 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 ...
1
vote
2answers
81 views

Projection for polygon intersection confined into one hemisphere?

I have polygons where each vertex is a (lon,lat) geographic coordinate. I want to find out if they intersect or contain each other. The polygons are guaranteed to never exceed a hemisphere (so they'll ...
0
votes
0answers
8 views

How to debug a QGis C++ plugin with Visual Studio 2008 [duplicate]

I have a plugin for QGIS 2.2 in C++ (legacy). I dont find how debugging this plugin, with Visual Studio 2008 (for evolution, etc.) Sorry for my bad english. Thanks you ! Paho
0
votes
0answers
25 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 aplicación en C++ que ...
0
votes
1answer
74 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 ...
0
votes
0answers
57 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 ...
0
votes
1answer
64 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? ...
1
vote
0answers
27 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
48 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
89 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' ...
3
votes
2answers
179 views

Fastest Way to Intersect Envelope with Multiple Feature Classes ArcObjects

I have the situation where I am doing a large number of intersections and I need to do them fast. The situation is I have a iMap with 1 or more layers and a series of envelopes, lots of envelopes. I ...
0
votes
0answers
14 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 ...
0
votes
0answers
57 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 ...
2
votes
1answer
188 views

Rearranging labels in screen to avoid overlapping

I have a map, with some icon over it. Every icon has a label next to it. When icons overlaps, labels are overlapped too. In this case, I want to move labels so they don't overlap anymore, with a line ...
0
votes
1answer
194 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 ...
0
votes
0answers
22 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()); ...
2
votes
1answer
890 views

Is it possible to query via bounding box in the Google Maps Static API?

We have a Qt program written in C++ to request wms tiles and display them. This works fine. Now we want to display imaginery from Google Maps and due to some restrictions in our program, we can't use ...