Mac Graphics API Testing - Metal

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Support Forum Agent
#1 - Dec. 2, 2015, 10:50 p.m.
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Hail and well met, Mac Users!

Our Mac Development team has been hard at work preparing Mac OS Metal Support for Legion, and we're ready to begin testing! Metal is a core graphics technology that gives games and apps near-direct access to the graphics processor on your Mac, delivering enhanced performance and a richer graphical experience. This allows the CPU and graphics processor to work more effectively.

By default, OpenGL is selected as the default rendering API. Metal currently needs to be enabled in your Game Settings, but we will be identifying the best rendering option for players when Legion goes live.

Metal is only available on Mac OS 10.11. For a full list of features and to upgrade, please visit Apple's OS X El Capitan page!

To Enable the Metal Graphics API

    1. Open your Options menu in-game and select System.
    2. Click to the Advanced tab.
    3. Under Graphics API, change the option to Metal and hit Apply. (Image)
    4. Restart your game client for the changes to take effect.

We're excited to be sharing this new feature and look forward to hearing your feedback! If you should run into any bugs during testing, please be sure to report them in our Legion Alpha Bug Report Forum.

Metal is available for the following system specifications

MacBook (Early 2015)
MacBook Pro (Mid 2012 or newer)
MacBook Air (Mid 2012 or newer)
Mac mini (Late 2012 or newer)
iMac (Late 2012 or newer)
Mac Pro (Late 2013 and newer)
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Support Forum Agent
#2 - Dec. 2, 2015, 11:20 p.m.
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Known Issues

1. If you have 4GB or more of Virtual RAM (VRAM), the client will crash.

Running the game in Metal on a supported device/driver may allow the game to launch. To set this outside of the game client:

    1. Open /Applications/World of Warcraft Beta/WTF/
    2. Open the file using TextEdit. If it does not exist, create a blank file in TextEdit and save to that location with the name
    3. Add the line gxAPI "MTL"
    4. Save the file and attempt to launch World of Warcraft.

2. When using metal, changing the window mode (like using command + M) will cause the water to become solid black

This issue can be worked around by changing your liquid settings after you've changed your window mode.

    1. Open your Options Menu and select System.
    2. On the Graphics tab, toggle the Liquid Detail setting and click Apply.
    3. Change your Liquid Detail setting to your preferred choice and click Apply.
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Support Forum Agent
#20 - Dec. 9, 2015, 3:36 a.m.
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Thanks for the sleuthing, guys!

We've been in touch with the team that works on the Nvidia Mac Drivers and they informed us of a memory leak issue that has been resolved in today's driver release. The issue is still outstanding on the 980ti (still being worked on), but all other cards should now be good.

I downloaded the new drivers on my machine here at the office, and am no longer experiencing the memory sinks. Give it a shot and let us know if you see an improvement!

Phone Edit: I was running on stock drivers and a CUDA update. Doesn't look like these web drivers are out yet for 10.11.2, so keep an eye out and let us know your experience!