cmake suppress finding package and set path manually - cmake

I'm currently automating my the installation process for multiple instances of an application. This application uses cmake for building and uses some libraries for which no findModule.cmake files exist. Since I'm could find a good example how to generate a findModule.cmake file for existing libraries for example OpenCascade. When setting up the buildprocess manually one can easily adapt the include and lib path in ccmake. Since I want to automate this I'm looking for a way to do this by passing the options to cmake on the command line. Here is how I try to achieve this for OpenCascade:
cmake -DOCC_FOUND:INTERNAL=TRUE -DOCC_INCLUDE_DIR:PATH=/usr/include/opencascade -DOCC_LIBRARY:FILEPATH=/usr/lib/libTKernel.so -DCMAKE_BUILD_TYPE:STRING=Release ..
Unfortunately this doesn't work. Since the option for building are build-depended, passing a previously configured CMakeCache.txt file is not working.
Thanks for any suggestions to achieve what I'm trying to do.

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cmake: package config for installing arbitrary file dependencies for a target

I am creating a cmake package config file (a Foo-config.cmake) for a pre-existing .dll not created by cmake.
The annoying thing is that the .dll depends on some data files.
When a user consumes my package in his own cmake project, I want the INSTALL target to install both the .dll and data files to his specified install location. I don't want him to have to write extra install() rules to do that.
Is it good practice to write the install() rules directly in my Foo-config.cmake? Or is there a better way to do this, maybe with set_target_properties()? I just couldn't find the appropriate property for associating arbitrary file dependencies to a target.
In an alternate universe where this .dll didn't already exist and I had to create it myself using cmake, would I need to create a custom Foo-config.cmake, or is there something in cmake that can automatically generate it for me to achieve the same thing?
FWIW the .dll is an internal legacy library and is normally built by Visual Studio and uploaded in a .zip file to our internal artifactory. I want us to migrate away from manually pulling down .zip files from artifactory and manually integrating the files into Visual Studio projects.
I've since found that there are a couple different ways to do this:
In the config file, simply create one or more variables for the files/dirs you want to install. Then install those using install(FILES) and/or install(DIRECTORY). More info: https://stackoverflow.com/a/46361538/189341
Use file(GET_RUNTIME_DEPENDENCIES). More info:
https://discourse.cmake.org/t/installing-a-pre-built-module-and-its-various-dependencies/5227
How to use cmake file( GET_RUNTIME_DEPENDENCIES in an install statement?
Is it good practice to write the install() rules directly in my Foo-config.cmake?
No.
From 480 *-config.cmake and *Config.cmake files on my system none calls install().
Or is there a better way to do this, maybe with set_target_properties()?
No.
In an alternate universe where this .dll didn't already exist and I had to create it myself using cmake, would I need to create a custom Foo-config.cmake
No. This is unrelated to if you create a .dll or not. If .dll exists, there is no need to create Foo-config.cmake anyway. It is your choice that you want to (or make users to) use find_package.
is there something in cmake that can automatically generate it for me
No.
If you don't intent to support find_package features - VERSION OPTIONAL_COMPONENTS PATHS HINTS CONFIGS etc. - then just go with include(). find_package is just include() with some extra options.
If you want to have install() in your find_package, then just protect it with a variable, like if (FOO_DO_INSTALL) install(....) endif().

How to build latex documentation with CMake?

Situation:
a small CMake C++ project
with a /doc folder, currently built via a custom Makefile in it.
Problems:
CMake and GNU make are two separate build systems and it is laughable to use more than one for a small and simple project.
make help does not list a doc target
Tried solutions:
Googled the problem, got suggested to use add_custom_target(). That sounds like the wrong solution because regenerating the target .pdf every time is ... I can't call it "inefficient" as it takes a couple of seconds. But is against C++'s ideal of "pay for only what you use" - yes.
How to generate documentation from .tex files given a working makefile is already present? With CMake.

CMake/CTest & gcovr: filename extensions?

After compiling with CMake with flags --coverage, and running my boost unit test programs, files with extension .cpp.gcda and .cpp.gcno are created. If I then run gcovr it claims it cannot find the .gcno files (error message ".gcno:cannot open graph file"). I could possibly move all output files but that would be really awkward/silly.
Related problems of other people could be solved by using CTest but as I am using Jenkins I'd like to stick to gcovr and use the cobertura xml output.
Ps. Maybe I should simply ask: how should I combine CMake with gcovr?
This is the solution we are using for the same setup inside jenkins: http://www.semipol.de/archives/320. You can simply grab the CMake macro from the linked RSC library for your own purposes.
Apart from that read something about a slightly changed format of the coverage files in recent gcc versions and it seems gcovr didn't keep up with that. But I cannot remember where I read this.

Making my program compile on both windows and linux, what should I do about libraries?

I'm using CMake to generate my makefiles and VC solutions. I have my program running on linux just fine. I'm using a bunch of libraries, e.g. Lua. On my linux computer I just link to them and make sure in include the headers. All of the .so files are in some standard place. On Windows though I'm not sure what to do. Should I just include the entire Lua project into my own repository and link to that instead? Do I install Lua to some standard place like c:\program files\lua5.1 and link to that? Something else?
Your libraries can be in any place, you just need to say - where are they.
Before running cmake set up pathes of all your extern libs with some .bat file:
set LIBRARYPATH =path\to\your\library\
set include=%include%;%LIBRARYPATH%\include
set lib=%lib%;%LIBRARYPATH%\lib
Start cmd, run this .bat and then cmake should find all
I would provide a configuration field/variable for ccmake that the user can or must specify.
The mark_as_advanced can be used to make a custom variable only appear in the advanced mode. This would be suitable if you have a standard path (as you have mostly on windows). Yet, it still let's the user specify the value if needed.
Or you can simply set a variable the with the 'set' command if you don't want it in advanced.
Just make sure you check if the users entered a valid value.

What is the correct way to customize the install output directory for each developer in CMake?

I've been working on an old game that I created CMake files for to get rid of a mix of Makefiles and visual studio projects. Everything is working well, but I'm having a hard time figuring out what the correct way to allow the developer to specify where the output files are copied to when install is run.
The issue is there are many DLLs and some custom targets that need their output copied into a directory structure that includes the game data (levels, art, sound, etc) before they can test the code.
My install commands currently uses a variable that I 'SET' at the top level CMakeLists.txt to specify the output directory. I've tried overriding it with -DD3_GAMEDIR on the cmake command line. That variable gets set in the CMakeCache, but the SET command appears to override it still.
Should I be checking the length of the variable before using SET to see if the user specified a value? That seems like a hack to me, but I'm having a hard time finding the correct way to do it.
Thanks!
The install target supports the DESTDIR parameter, so you could do something like:
make install DESTDIR="C:\RootGameDir"
The other option is to only set the variable if it isn't already set (if(myVar)), but I personally prefer the DESTDIR solution.
Here is the anwser, according your cmake version:
SET(CMAKE_VERSION "${CMAKE_CACHE_MAJOR_VERSION}.${CMAKE_CACHE_MINOR_VERSION}")
IF("${CMAKE_VERSION}" STRGREATER "2.4")
SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY /path/of/your/install/${CMAKE_BUILD_TYPE}/bin)
SET(CMAKE_LIBRARY_OUTPUT_PATH /path/of/your/install/${CMAKE_BUILD_TYPE}/lib)
ELSE("${CMAKE_VERSION}" STRGREATER "2.4")
SET(EXECUTABLE_OUTPUT_PATH /path/of/your/install/${CMAKE_BUILD_TYPE}/bin)
SET(LIBRARY_OUTPUT_PATH /path/of/your/install/${CMAKE_BUILD_TYPE}/lib)
ENDIF("${CMAKE_VERSION}" STRGREATER "2.4")
What about using the various CMAKE_INSTALL_PREFIX, PROJECT_SOURCE_DIR and PROJECT_BINARY_DIR?