Recently I've started working on a C++ project that uses the CMake build
+system.[1] The first thing I was in charge of
+doing was fixing the build, as one of the dependencies is the SeetaFace2
+project.[2] Originally you had to have the
+SeetaFace2 project in a directory adjacent to the SeetaRest project directory,
+and you would manually compile SeetaFace2. This, for obvious reasons, is not a
+good build setup. So my task was to integrate it directly into the build using
+CMake's ExternalProject
+module.[3]
Generally, for those of us used to the way things work on Linux, generally +speaking you want to work solely with the dependencies you can install from your +distribution's repositories. The problem with this is, save for certain very +popular libraries/tools, there are some inconsistencies as to what packages may +be available in different distributions, what versions they have available, or +even if it's compiled with the flags you need for your project. It's still ideal +to link to something from the repositories, but it's not always possible.
+ +This is where ExternalProject comes in. This allows for
+dependencies to be downloaded and compiled with specific options that best suite
+the project. It's also done in a rather simple manner. Just by looking at the
+SeetaFace2.cmake module for the project, it's fairly easy for
+anyone with a basic knowledge of CMake syntax to see how this project is built
+and setup.[4] And since you're having to build an
+entire other project, it's also helpful that you have the option of choosing
+which targets to build (instead of the entire project).