[OSX] Unofficial Path of Exile port - 30/12/2018 status update

Unfortunately, I have to say at this moment, it is not possible to make working port of PoE on OSX, due to several reasons:

However the main reason is OSX system itself
This game relies heavily on streaming data from big file. While this is not problem on Windows or Linux, OSX does not like it, especially when mmap() method is used to accessing this data. OSX implementation of mmap is extremely slow on large files, and over the time, the game file (content.ggpk) has bloated from <5GB during alpha to 18GB+ nowadays. This is also the reason why the game loading times gets slower and lags during gameplay higher with every patch.

For technical people, lets consider this C code

This code tests 1000 mmaps allocation in 4kB, 64kB and 1024kB blocks on file io_benchmark.dat. On Linux, this code runs <1s (actually for 4kb its <100ms). While on OSX it runs for at least 10+seconds regardless of amount of data read. This is reason behind slow loading times and lags ingame. If the data resides on HDD/SDD or directly in memory, it does not matter, the speed remains about same.

To make this game works trough wine on OSX in playable fashion, one of the following has to happen

1) Apple will rewrite mmap implementation in their OSX kernel (unlikely, I opened bug report for this years ago, and it got closed as duplicate, no progress)

2) Wine would need to rewrite their memory management to avoid using mmap. This is also unlikely, because alternate approaches would slower the allocation on Linux, while it would speed it up on OSX, but OSX is not Wine main target

3) GGG would change their data system to instead using content.ggpk to large amount of smaller files (max 100MB, ideally one file per each effect). I guess this is the most likely scenario, if GGG is willing to support PoE on Mac at least passively.

Also, as most of you noticed, newer OSX has implemented checks on created application, and will complain about corrupted app even if it is ok. This can be workaround by giving specific instructions how to install the game from scratch, however until one of the above happens, there is no point in writing such guide.

So how can I play the game on Mac
Not trough wine, that's for sure. However there are alternatives but each one require installation of Windows

Best performing:
Bootcamp - you will end up in dual boot between OSX and Windows. This gives native and full performance, but you need to reboot each time to change OS.

Virtualization - This does not give you full performance, and comes with additional cost as none of the major provider does not give the app for free.
The best performing one are Parallels Desktop and VmWare Fusion. These have full DX9 implementation and nowadays possibly even DX11, there is minor performance loss (~10-20%) compared to bootcamp.
You can also try Oracle VirtualBox which is for free and should have good DX9 support, but it would definitely be the slowest solution (not as slow as trough wine though).