Bad drawing performance in ProTools - What's different?

[hugoderwolf]

I’m experiencing low framerate drawing my GUI in ProTools on macOS. In all other hosts it’s smooth. It gets far worse when zooming the UI larger. It’s acceptable-ish at 100%, but gets much more sluggish with larger sizes.

The GUI draws completely in a container that’s scaled with window size, almost everything is vectorized. Graphs are repainted on a 20Hz timer. There is nothing in my own drawing code that would take more time when drawing more pixels. I need to do some more debugging to find out if there’s a specific component that this is attributed to.

I suspect this could also be related to a different problem I’ve seen in ProTools exclusively:

Drawing a transformed image - different behavior in ProTools and when Snapshotting

I’m drawing a graph with a complex gradient pattern using a neat trick: it’s simply a 2xN image in memory that I draw with a transform to the correct bounds I want, using Graphics::drawImageTransformed(). That way I get the smooth gradients I want through the interpolation when drawing the image. Curiously, I found cases where the interpolation isn’t smooth and I get much lower resolution in the result. This happens (so far) in ProTools on macOS (not on Windows), and when I screenshot the edito…

Both issues suggest that there is some significant difference in the way the editor is drawn to screen in ProTools/AAX compared to other hosts/formats. So far I have no idea what that could be. How 'bout you folks?

[hugoderwolf]

Cool, loading the plugin in the developer build of ProTools the problem goes away. That’ll be a fun one to debug…

[ttg]

I’d suggest contacting Avid.

Also, notice this is a change related to macOS Core Graphics. this issue seems to start following some changes from Sonoma onwards.