When using Cmake, the source direction /apriltag does not contain a CMakeLists.txt file.

[StarrKiss]

Here is my log for trying to build on Manjaro Linux:

`- The C compiler identification is GNU 10.1.0
-- The CXX compiler identification is GNU 10.1.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc - works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ - works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found OpenCV: /usr (found version "4.3.0")
CMake Error at CMakeLists.txt:12 (add_subdirectory):
The source directory

/home/gstarr/Documents/tools/AprilTools/apriltag

does not contain a CMakeLists.txt file.

-- Configuring incomplete, errors occurred!
See also "/home/gstarr/Documents/tools/AprilTools/build/CMakeFiles/CMakeOutput.log".
`

[jlspringborn]

Hey man. I just downloaded apriltools and ran into the same problem. I'm not sure if you got help already but I thought I'd mention how I fixed the problem just in case. The apriltag directory was downloaded without files in it. So what I ended up doing was clicking on the apriltag directory found at this link:
https://github.com/AprilRobotics/apriltag/tree/43ca2c4db31e685dcecb928d5f5ae7659677e98b

Once you download those files all you need to do is drop them into the apriltag directory and then running the cmake command will no longer give an error. I just did it and it's now working working for me. Good luck I hope that helps!

[rizerphe]

I think using specifically git --recursive clone https://github.com/thegoodhen/AprilTools, with --recursive, will solve the issue