Issue with ItkVtkGlue - c++

I'm trying to run this example: http://www.itk.org/Wiki/ITK/Examples/IO/ImageFileReader
But, get the following when I "configure" in CMake:
CMake Error at CMakeLists.txt:11 (find_package):
By not providing "FindItkVtkGlue.cmake" in CMAKE_MODULE_PATH this project
has asked CMake to find a package configuration file provided by
"ItkVtkGlue", but CMake did not find one.
Could not find a package configuration file provided by "ItkVtkGlue" with
any of the following names:
ItkVtkGlueConfig.cmake
itkvtkglue-config.cmake
Add the installation prefix of "ItkVtkGlue" to CMAKE_PREFIX_PATH or set
"ItkVtkGlue_DIR" to a directory containing one of the above files. If
"ItkVtkGlue" provides a separate development package or SDK, be sure it has
been installed.
It seems I need "ItkVtkGlue"? Where can I download it? And, what should I do to combine it with the program?

VtkGlue is a module within ITK, which by default is not built. You need to enable this module with cmake when you build ITK. Also, before you do this, you need to download and build VTK (which is very similar to building ITK). Assuming you are on a unix-like system, have VTK installed, have a src and bin folder for ITK, and are sitting in the bin folder, I would do:
$ ccmake ../src -DModule_ItkVtkGlue=ON
The last option turns the ItkVtkGlue module on by default. You can also do this in the curses GUI without passing this option: press t to get the advanced options, use the arrow keys to scroll down to Module_ItkVtkGlue, and, once there, use the enter key to toggle this option ON. Finally, configure, configure, configure, generate as usual, and then:
$ make
$ sudo make install
Many of the examples on the ITK Wiki use VtkGlue. You can see how to format your CMakeLists.txt file by looking at any of those.

Related

Custom library directory for cmake

For my project, I am building specific versions of the dependency libraries in a separate folder, say, /home/ubuntu/libs. I will use real libraries as an example, however, the question is pretty generic.
I was able to build the freetype library and make installed the headers into /home/ubuntu/libs/include, the built library into /home/ubuntu/libs/lib and also added the freetype-config.cmake to /home/ubuntu/libs/lib/cmake.
Now, I am trying to build the freetype-gl library that depends on freetype and has a line
find_package(freetype REQUIRED) in its CMakeLists.txt.
Typically, when I install the freetype library to a common path like /usr/local/lib or /usr/lib, cmake picks up the *-config.cmake files from the corresponding ./cmake directory. However, when I call it with
cmake -DCMAKE_TOOLCHAIN_FILE=/my/custom/toolchain -DCMAKE_LIBRARY_PATH=/home/ubuntu/libs/lib -DCMAKE_INCLUDE_PATH=/home/ubuntu/libs/include /path/to/freetype-gl
it fails with the following error
CMake Error at CMakeLists.txt:102 (find_package):
By not providing "Findfreetype.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "freetype",
but CMake did not find one.
Could not find a package configuration file provided by "freetype" with any
of the following names:
freetypeConfig.cmake
freetype-config.cmake
Add the installation prefix of "freetype" to CMAKE_PREFIX_PATH or set
"freetype_DIR" to a directory containing one of the above files. If
"freetype" provides a separate development package or SDK, be sure it has
been installed.
What am I doing wrong? How to show the place of "freetype-config.cmake" to cmake.
as you state in your second paragraph:
I was able to build the freetype library and make installed the headers into /home/ubuntu/libs/include, the built library into /home/ubuntu/libs/lib and also added the freetype-config.cmake to /home/ubuntu/libs/lib/cmake.
find_package() in CMake works in a way that it checks the standard system paths on default. If you are using CMake version 3.17 you can (instead of reading the documentation) view these paths simply by adding this line to your CMakeLists.txt
SET(CMAKE_FIND_DEBUG_MODE TRUE)
In your case what you need to do is point CMake in the right direction of the cmake file you are looking for. In your case that would be the /home/ubuntu/libs/lib/cmake. So somewhere in the top of your CMakeLists.txt (before you call find_package()) add this line:
LIST(APPEND CMAKE_MODULE_PATH "/home/ubuntu/libs/lib/cmake")
Provided that this bash command:
ls /home/ubuntu/libs/lib/cmake | grep "*.cmake"
Returns an occurance of freetypeConfig.cmake (you get the drill :) )
You can read about CMAKE_MODULE_PATH variable here: https://cmake.org/cmake/help/latest/variable/CMAKE_MODULE_PATH.html
In short your CMake doesn't find the config file because it is not in the standard path where it expects to find it.
EDIT: You can ofcourse do the same via these variables as the error suggests - CMAKE_PREFIX_PATH or freetype_DIR
Presumably you also don't want the libraries you build to find their dependencies installed on our system, if any.
I've spent some time investigating how to isolate CMake builds, and my best recipe is below.
First, the terminology:
An installation "prefix" of a library is a directory where the binaries and headers are installed (normally in include and lib subdirectories). I preder distinct prefixes for each library.
A "dependency" of a library is any of other library it needs when compiling.
CMake path separator - the character used to separate path lists for CMake. It's : character on Windows and ; on Linux (when cross-compiling, the host system matters, not the target).
Yes, it's the opposite of what the documentation claims.
By Windows I mean MSYS2. If you want to build outside of it, check that : is still the right separator.
Environment variables for CMake:
PKG_CONFIG_PATH to empty string
PKG_CONFIG_LIBDIR to a :-separated list, for each dependency add <prefix>/lib/pkgconfig and <prefix>/share/pkgconfig.
(I didn't need to do it for any library I used, so this is theoretical. But in any case don't leave this variable unset, at least use an empty string. Otherwise some undesired dependencies from your system might leak in.)
CMake flags:
-DCMAKE_INSTALL_PREFIX=... - the installation prefix for this library.
-DCMAKE_PREFIX_PATH=... - a path list: the installation prefix, followed by the prefixes of all dependencies. Use the CMake path separator, as described above. All paths here must be absolute.
-DCMAKE_FIND_USE_CMAKE_SYSTEM_PATH=OFF
This prevents CMake from finding some system-wide dependencies. If I remember correctly, not doing this makes CMake look for dependencies in directories listed in PATH and their parent directories, which is annoyting.
This has an undesired effect of disabling some ..._SYSTEM_... CMake variables, so we can't use those, even though some of them would be more appropriate.
-DCMAKE_STAGING_PREFIX=/. On Windows hosts replace / with the current drive name, e.g. C:.
This is only useful when cross-compiling, to disable the effects of CMAKE_FIND_ROOT_PATH in the toolchain file, which otherwise limits dependency search to that path.
This also messes up the installation path that would otherwise be taken from CMAKE_INSTALL_PREFIX, the fix is explained below.
Only on Windows hosts:
-DCMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH=OFF - otherwise CMake tends to look for dependencies in the PATH and parent directories, which is annoying. This is hardcoded to only happen on Windows hosts, which is nonsense and was reported here.
We don't want to set this unconditionally, because it has a side effect of requiring all your toolchain executables to be in the same directory, which is annoying in general, but IMO tolerable on Windows.
It also prevents CMake from searching for executables in PATH, so we also need...
-DCMAKE_PROGRAM_PATH= - set this to the contents of PATH, with the original separator replaced with the CMake path separator. At least on MSYS2 the separators are the same, so no modifications are needed.
-DCMAKE_MAKE_PROGRAM=ninja -GNinja - here CMAKE_MAKE_PROGRAM is strictly necessary on Windows hosts because of CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH=OFF, and doesn't hurt on other platforms. -G... is to make sure CMake doesn't pick a different generator that doesn't match CMAKE_MAKE_PROGRAM. You can use any other generator+program if you wish.
Then build with cmake --build <build_dir> -j<num_threads> as usual.
Install with cmake --install <build_dir> --prefix <prefix>. We need to explicitly set prefix because of CMAKE_STAGING_PREFIX=/.

Integrating and running OpenDDS with QTCreator

I have installed the latest version of OpenDDS I followed the configuration and installation documents provided.
I can perfectly run opendds examples with the terminal.
I need to integrate OpenDDS with QT, since OpenDDS supports CMake
I have tried to load CMakeList.txt in qt for messenger_1 and messeger_2 examples I got, unknown CMake command "OPENDDS_TARGET_SOURCE"
I wasn't able to run the IShape example either.
This most probably means that CMake does not find the OpenDDS package files.
CMake reads the CMake variable CMAKE_PREFIX_PATH and extends its default package search path by this. By default Qt Creator sets that to your Qt install path (which is good since you want to use Qt), but to use OpenDDS you need to point it to its source/install path as well (see the OpenDDS CMake documentation).
You can add multiple paths to CMAKE_PREFIX_PATH, separated by ; on Windows, or : on Linux/macOS.
In Qt Creator the CMAKE_PREFIX_PATH is set up in the CMake Configuration part of the Kit. So:
Open "Options > Kits > Kits" and choose the kit you use for your project
Scroll down to CMake Configuration and click Change
Find the CMAKE_PREFIX_PATH line and change it to something like
CMAKE_PREFIX_PATH:STRING=%{Qt:QT_INSTALL_PREFIX};C:\path\to\OpenDDS or if you are on Linux/macOS
CMAKE_PREFIX_PATH:STRING=%{Qt:QT_INSTALL_PREFIX};/path/to/OpenDDS
You might need to close and re-open the project after that (but maybe not).

CMake "find_package" command on a package that was not installed is unexpectedly successful

I am following chapter-02/recipe-06 in "CMake Cookbook". This particular example requires the Eigen C++ libraries.
I attempted to build the example and got the error that Eigen was not found.
CMake Error at CMakeLists.txt:9 (find_package):
Could not find a package configuration file provided by "Eigen3" (requested
version 3.3) with any of the following names:
Eigen3Config.cmake
eigen3-config.cmake
Add the installation prefix of "Eigen3" to CMAKE_PREFIX_PATH or set
"Eigen3_DIR" to a directory containing one of the above files. If "Eigen3"
provides a separate development package or SDK, be sure it has been
installed.
This was expected because the library was not installed on my system.
I then downloaded the ".zip" file for the Eigen libraries and unzipped it to an arbitrary location outside of my project. I created a "build" folder in the Eigen directory and ran cmake .. in the "build" folder. (I only ran cmake - I did NOT build or install the package.)
After running CMake on the Eigen build directory, I went back to the example code for "recipe-06" and it was magically able to find the Eigen library and built successfully even though Eigen was never built or installed.
Somehow just running CMake in the Eigen project made CMake aware of the Eigen libraries location. After doing this, any projects that do find_package to find Eigen3 somehow get the ${Eigen3_DIR} variable defined and are able to find it.
Looking at the CMake documentation for find_package I don't see any explanation of why this works. Eigen is not in any of the typical locations that find_package searches. According to the documentation it looks like it should NOT be found.
Even more interesting - it doesn't matter where I put Eigen on my system. I can put it literally anywhere and it will still find it.
According to everything I see in the documentation it should not be found... but it is found. So the question is how? Why does this work?
Additional info: I am using CMake version 3.13.3
There are 2 "origins" of XXXConfig.cmake files, used internally by find_package() call.
Usually, XXXConfig.cmake file is produced when the project is installed, and the file contains information about installed libraries and headers.
But CMake provides also an export() command, which allows to export build tree.
export(PACKAGE <name>)
Store the current build directory in the CMake user package registry for package <name>. The find_package command may consider the directory while searching for package <name>.
Eigen's CMakeLists.txt uses export() command, so the project becomes detectable with find_package just after running cmake for Eigen.

Using CMake to find dependencies in an application-specific subfolder

In spite of many years of coding large-scale C++ applications, I do not understand how find_package is supposed to work in a medium-size CMake project, ASSUMING that I want to build the source to dependent packages myself and not simply rely on large systems like opencv, pcl or boost being installed somewhere in a system folder. I can't can't believe that I'm the only person in the world who has shipped multiple OpenCV and other open-source apps, has worked with meta-build systems like NAnt and SCons on major game projects, yet can't understand the most basic things about how CMake works or find a tutorial answering these questions.
In the past, I have essentially hacked around not understaning find_package by setting all the foo_DIR values by hand as CMake complains until I get a working folder.
I would like to run through a simple example which I'm working on right now, and dearly hope someone can explain what I'm doing so wrong.
Firstly, some assumptions:
I want to build everything for both MacOS and Windows, ideally via CMakeGUI. MacOS should build XCodeProjects and Windows should build Visual Studio Solutions.
Where there are dependencies, I want to compile them myself, so I have debug symbols and can modify the dependency source (or at least debug into it.)
No installation of pre-built binaries into system folders, i.e. no use of sudo port install opencv/pcl, etc on mac.
I have multiple projects, and prefer to keep a project and its dependencies in a single folder.
For the purposes of a concrete example, suppose I am building this project, although it's an arbitrary choice to illustrate the process and confusion I suffer:
https://github.com/krips89/opendetection
This lists dependencies, which I have intentionally reordered here so that I can take them in order, as follows:
find_package(OpenCV REQUIRED)
find_package(Eigen REQUIRED)
find_package(Boost 1.40 COMPONENTS program_options REQUIRED )
find_package(PCL REQUIRED)
find_package(VTK REQUIRED)
I would like to have all of these dependencies downloaded and configured in a single path (let's say c:\src on Windows, and ~\src on Mac for simplicity), NOT in a system path. Assume that the actual folder is a sub-folder for this project, and no a sub-folder for all projects. This should also allow for side-by-side installation of multiple projects on the same computer.
Taking this one step at a time:
(1) I clone openCV from https://github.com/opencv/opencv, sync to tag 3.1, configure into the folder opencv_build folder, build and install into opencv_install. I've done this so many times it's pretty straightforward.
(2) As above, but for eigen (although building for eigen doesn't actually do anything s it's a template library. I install to a folder eigen_install
Taking directory shows a series of folders for downloaded dependencies. I have assumed a convention where , and are source repos, and their following _build folders are the "WHere to build the binaries" folders in CMakeGui.
$ ls
boost_1_40_0 opencv opendetection_build
eigen opencv-build opendetection_data
eigen_build opencv_contrib pcl
eigen_install opendetection
All good so far, now let's try to configure opendetection and generate a solution into opendetection_build, and find pendetection's dependencies from within the ~/src folder, that is for the first two dependencies, I hope to find opencv and eigen in the opencv-build and eigen-build folders.
OpenCV immediately fails, as expected, saying:
Could not find a package configuration file provided by "OpenCV" with any of the following names:
OpenCVConfig.cmake
opencv-config.cmake
Add the installation prefix of "OpenCV" to CMAKE_PREFIX_PATH or set "OpenCV_DIR" to a directory containing one of the above files. If "OpenCV" provides a separate development package or SDK, be sure it has been installed.
That's good, because I want to explicitly tell CMake to look for dependent packages under my ~/src folder. Question: Is the use of CMAKE_PREFIX_PATH=/users/foo/src the recommended way to accomplish what I want - looking for all sub-packages under a specific path?
Following this, CMake finds OpenCV (good), and sets OpenCV_DIR = /Users/foo/src/opencv-build.
Question: Given that I have made an "install" to opencv-install (using CMAKE_INSTALL_PREFIX and building the Install Target Of OpenCV, shouldn't it find OpenCV in the opencv-install folder not opencv-build?
Moving on to eigen, I have configured and built eigen, and installed it to ~/src/eigen-install, which since it is a subfolder of CMAKE_PREFIX_PATH (~/src) I might expect to be found. But it doesn't seem to be. Can somebody explain to me what I'm not understanding? Particularly given that Eigen in a template library, and that there are at least three folders (eigen, eigen_build and eigen_install) under CMAKE_PREFIX_PATH which I would have thought CMake would find something in, I assume I must be doing something wrong here. I KNOW from past experience, I can set EIGEN_INCLUDE_DIR by hand in CMakeGUI by hand, and continue hacking forth, but that just seems wrong.
I'm more than willing to write up a web page explaining this for future people as dumb as me if one does not already exist, although I can't understand how use of CMake for basic project configuration and generation is apparently so obvious to everyone but so opaque for me. I have actually been using CMake for some years, usually by just manually setting Boost_INCLUDE_Dir, Foo_INCLUDE_PATH etc manually, but clearly this is not the right solution. Generally, after spending a couple of days fighting through the various packages to generate a solution by manually setting INCLUDE PATHS, LIBRARY PATHS and other options, I just deal with the solution and don't touch CMake again. But I would love to understand what I'm missing about find_package for my (surely not uncommon) use case of wanting to control my project dependencies rather than just using sudo port install * and installing random versions of projects to my global system folders.
As error message says, CMAKE_PREFIX_PATH should be set to installation prefix of the package. E.g., if the package has been built using CMake, this is CMAKE_INSTALL_PREFIX variable's value, if the package has been build using Autotools, this is value of --prefix option used for configure it, and so on.
CMake doesn't search every directory under CMAKE_PREFIX_PATH. That is why specifying it as /users/foo/src is useless if you have the package installed at /users/foo/src/eigen-install.
Instead, you may install all 3d-party packages into /users/foo/src/install, and use that path as CMAKE_PREFIX_PATH in your main project.

OpenCV Contrib Module Installation on Mac

I have searched here on StackOverflow and other sites to figure out how to install OpenCV 3.0 the Contrib Modules. I have downloaded the extra modules and extracted the zip file to the /opt/local/include/opencv2/opencv_contrib/ folder. I've navigated to the /opt/local/include/opencv2 folder and typed the following command in the terminal:
cmake -DOPENCV_EXTRA_MODULES_PATH=/opt/local/include/opencv2/opencv_contrib/modules/ /opt/local/include/opencv2
I get:
-bash: $: command not found
If I just type in cmake -D, I get:
CMake Error: -D must be followed with VAR=VALUE.
CMake Error: Problem processing arguments. Aborting.
So I know it recognizes the cmake command with the -D tag.
Any ideas?
Nobody said that installing OpenCV and their modules was easy.
Just like you, I already had Opencv 3.0.0 installed and running and wanted to add the contrib modules.
Steps:
1st- Delete and download again the OpenCV3.0.0 folder (is not necessary, but after twitching around, I prefer to download a new one) download the openccv_contrib and place them in the same folder.
2nd- Go to the OpenCV3.0.0 and create the build folder.
3rd- Open Cmake gui and follow the steps form https://github.com/itseez/opencv_contrib.
3.1- Fill “Where is the source code” with the rotute of where is openCV3.0.0. (my case /Users/Rafearl/Program/ComputerVision/opencv-3.0.0)
3.2- Fill “Where to build binaries” with the build route(/Users/Rafearl/Program/ComputerVision/opencv-3.0.0/build)
3.3- Press configure
3.4- In the search bar search for “OPENCV_EXTRA_MODULES_PATH” and fill with the Opencv_contrib modules(/Users/Rafearl/Program/ComputerVision/opencv_contrib-master/modules)
3.5- Click configure again and then click generate. By default current generator: Unix makefiles
4th- In terminal go to your build folder
5th- make -j4 (4 is the number of cores of the processor)
6th- sudo make install
Now you can check the lib in the build folder that the contrib libraries are added
If you don´t want to download the OpenCV3.0.0 again just follow the same steps without downloading or deleting anything.
If you already have Opencv in Xcode, everything should work but just as a piece of advise; many of the OpenCV2.4 examples does´t work in the 3.0 version.