No Metal acceleration on iMac 27" with Radeon Pro 580??

[soeren68]

Hello,

 

yesterday I bought and installed Affinity Photo and I'm quite happy with it...

However, now I looked into the preferences and there I read (in German, of course ;-)):

"No compatible GPU" (I attached a screenshot)

That would be a surprise for me, because the Radeon Pro 580 is the fastest in the iMac-lineup, with the exception of the iMac Pro, of course.

Is that normal? Will it be fixed with future updates?

 

Greetings from Hamburg,

Sören

 

P.S.: macOS High Sierra, 10.13.3

[Butler To Cats]

See this thread: 

 

 

[R C-R]

3 hours ago, obtusity said:

See this thread: 

 

That topic seems a bit confusing but I think the important part is in this post by @Chris_K

Quote

This feature is only enabled for Intel HD and Intel Iris integrated GPUs found in the more recent Macs.

Apple has a list of the Macs that use those integrated GPUs here. If your Mac is not on that list then the option won't apply to you, & as he said in this post, if you select "Metal" in the Display (Darstellung) drop down you are already using 'full metal' hardware acceleration.

[James Ritson]

57 minutes ago, R C-R said:

 

That topic seems a bit confusing but I think the important part is in this post by @Chris_K

Apple has a list of the Macs that use those integrated GPUs here. If your Mac is not on that list then the option won't apply to you, & as he said in this post, if you select "Metal" in the Display (Darstellung) drop down you are already using 'full metal' hardware acceleration.

 

The display acceleration and Metal compute hardware acceleration are two entirely separate things - using Metal for display acceleration just means it's used to present to screen (i.e. the canvas view). It should be faster than OpenGL, but between the final High Sierra beta and the public release something changed and presented some issues with the way Affinity's Metal renderer is implemented. It's hopefully something that will be addressed in the future. In the meantime, the OpenGL renderer was tweaked to compensate (it's noticeably faster in 1.6 than 1.5).

 

Metal compute is hardware acceleration, and is a back port from the iPad development where Metal implementation was necessary to achieve good performance. In particular, equirectangular projection absolutely flies using Metal compute, often hitting 60fps at 5K resolutions and above. Complex live filters like Twirl and other distortions should also redraw much faster. At the moment, however, it's limited to integrated graphics chips which you'll typically find either on MacBook models or the 21" iMacs.

 

You'll notice enabling Metal compute will use the integrated GPU, but you don't need to check "Use only integrated GPU". Photo can still use the discrete GPU for presenting to screen and the integrated GPU for Metal compute quite separately.

 

Hope that clears it up a bit!

[R C-R]

41 minutes ago, James Ritson said:

At the moment, however, it's limited to integrated graphics chips which you'll typically find either on MacBook models or the 21" iMacs.

Good to know. So now I will have to compare the performance of my wife's 21" iMac that has an Iris Pro Graphics 6200 GPU with my own (on paper otherwise faster) iMac on some of the Photo filters. Should be interesting. 

[soeren68]

Many thanks to all for your answers! Now this is cleared up for me...