build instructions for macOS

[matatata]

Hi,

since I've worked a bit on some smaller issues on the macOS build I sometimes get requests of users not being able to use my macOS build https://github.com/matatata/opentrack/releases, because they're not signed.

Perhaps you could add some instructions in the README, so they interested MAC users can build opentrack themselves: Here's I am able to successfully build a macOS opentrack:

Prerequisits: Install macports

export PATH=$PATH:/opt/local/bin:/opt/local/libexec/qt5/bin
export OTR_OSX_ARCH=arm64 # this is not necessary when building on Intel-Mac or perhaps set to x86_64
sudo port install qt5 cmake ImageMagick
git clone --recurse-submodules https://github.com/opentrack/opentrack.git
cd opentrack cmake -S . -B build --toolchain cmake/apple.cmake
cd build
make install
open install # in this folder you should find the opentrack.app

Greetings, Matatata

[matatata]

I'll first try messing around with the linux build instructions (https://github.com/opentrack/opentrack/wiki/Building-on-Linux). I did not know about ccmake and I'm currently trying to get the modules that rely on opencv to build

[matatata]

OK that helped. The linux instructions helped a lot. Setting the OpenCV-Dir is crucial. Now I have a PointTracker! This is how it worked for me:

Install macports https://www.macports.org/

export PATH=$PATH:/opt/local/bin:/opt/local/libexec/qt5/bin
export OTR_OSX_ARCH=arm64 # build arm64 . For intel set to x86_64 or remove
sudo port selfupdate
sudo port install qt5 cmake ImageMagick create-dmg opencv4
git clone --recurse-submodules https://github.com/opentrack/opentrack.git
cd opentrack

export OpenCV_DIR=/opt/local/libexec/opencv4/cmake
cmake -S . -B build --toolchain cmake/apple.cmake
cd build
make install

[matatata]

I finally managed to make a build that even includes the neuralnet-tracker. See https://matatata.github.io/MacOpentrack.html

It is great to be able to track using a regular webcam on macOS too!