• Point3f was added to type traits but was missing in the "own" package; fixed.

Note to test the build you'd need to get & build ADE first:

$ git clone https://github.com/opencv/ade.git
$ mkdir ade_BUILD
$ cd ade_BUILD
$ cmake ../ade -DCMAKE_INSTALL_PREFIX=install -DCMAKE_BUILD_TYPE=Release
$ make
$ make install

After that:

$ mkdir gapi_BUILD
$ cd gapi_BUILD
$ cmake /path/to/opencv/modules/gapi -Dade_DIR=/path/to/ade_BUILD/install/share/ade -DCMAKE_BUILD_TYPE=Release
$ make

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under Apache 2 License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
• The PR is proposed to the proper branch
• There is a reference to the original bug report and related work
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake