Performance Issue Linked to certain Canvas sizes

[Tox]

What Application are you using? [Designer/Photo/Publisher]
Affinity Photo 2

1. Are you using the latest release version?
   Yes
2. Can you reproduce it?
   Yes
3. Does it happen for a new document? If not can you upload a document that shows the problem?
   Yes and I can upload a document which shows this input lag, but I can't visualise the lag itself.
4. If you cannot provide a sample document then please give an accurate description of the problem for example it should include most of the following:

•    What is your operating system and version (Windows 11, OSX Ventura, iOS 16 etc)?
  Operating System is MacOS Ventura 13.5.2 (22G91) Running on a MacBook Pro with M1 chip and 16 GB of RAM
•    Is hardware acceleration (in Preferences > Performance) ON or OFF ? (and have you tried the other setting?)
  It's turned on, I haven't tried it without it.
•    What happened for you (and what you expected to happen)
  I've created two different Documents with the following settings:
  Document A:
  Resolution: 12000px * 6000px
  DPI: 400
  Colors: RGB/32 Bit
  Document B:
  Resolution: 10000px * 6000px
  DPI: 400
  Colors: RGB/32 Bit
  Both had a huge input lag of about 3 seconds or more from Input to brush stroke appearing on the Canvas.
  At first I was thinking that it might be a performance issue, however if I use a HIGHER resolution (like 20000px * 6000px for Document A or 20000px * 12000px for Document B), I did not have that performance issue.
•    Provide a recipe for creating the problem (step-by-step what you did).
  I created a Document with the attributes mentioned above and tried to do a stroke on the Canvas
•    Screenshots (very handy) or a screen capture/video.
  I'll provide a video, with not external devices connected. It shows the performance issue at 12000px * 6000px, and then how it isn't there at 20000px * 6000px, in the same document with a resized canvas. I used my trackpad for doing the strokes so they are a bit... chaotic.
•    Any unusual hardware (like tablets or external monitors or drives that may affect things) or relevant other applications like font managers or display managers.
  There are no external devices connected (No Bluetooth Keyboard, Headphones, Mouse, anything) except for a Huion Kamvas 16 2021 with its driver. However, the problem also occurs, if I disconnect the Huion and don't connect anything.
•    Did this same thing used to work and if so have you changed anything recently? (software or hardware)
  I updated my Mac from I think 13.3.1 to 13.5.2, but I don't remember if it used to work before that. Tho it is possible.

Canvas with Performance issues.afphoto

[Dan C]

Hi @Tox,

Welcome to the Affinity Forums & thanks for your report!

In my testing, this appears to be more heavily linked to the 32bit colour space being used, rather than the exact size of the canvas.
I have tested using a few different sizes, including the exact ones provided above and I'm not seeing quite the same behaviour you have described - any large canvas using 32bit & 400DPI appears to show this lag for me when painting with the Paint Brush tool. The lag I'm experiencing isn't as bad as shown in your recording, though does not seemingly change with a higher resolution (ie 20000 * 6000px).

Can you please navigate to Affinity Photo 2 > Settings > Performance and provide a screenshot of your settings here for me please?

Although there technically shouldn't be an issue with this, out of interest is there a reason you are creating such large, pixel dense documents using 32bit colour? As this means there is a lot for the app to calculate when painting on said canvas.

Many thanks in advance

[Tox]

Gald to be here!

I mean yeah, on the 20000*6000 px I do have lag too, but it's more like around 100 ms. Recognisable, but not disrupting. The 10000*6000px however has like 4+ seconds.

Screenshot is attached!

Well... you see. I'm new to (digital) art and am just now trying to learn to paint. And I have no clue what the numbers really mean.
Yeah that's essentially the reason. I use a high resolution because I like to zoom in to my strokes and if they're pixely my brain has issues really getting the structure. High Resolution makes it easier for me to not get distracted by minor things.
When it comes to colors I was like: I got Apple Products with those Retina Screens and I wanted to use RGB/32 because that offers more colors and I figured it could look more vivid on said screens.
For DPI: I got no damn clue. An artist I know usually goes with 400, so I picked that too.
Could I theoretically use 100 DPI and upscale it to 400 dpi if needed later ? To reduce strain I mean.

[Dan C]

My sincerest apologies for the delayed response, many thanks for providing that for me!

I'd recommend disabling Metal Hardware Acceleration, then changing the Display option to OpenGL, restart the app as prompted and then try painting once again. Certain documents/workflows can benefit from using Metal, however this is not always the case - so I recommend trying both options to see which works best here.

On 9/11/2023 at 6:31 PM, Tox said:

Yeah that's essentially the reason. I use a high resolution because I like to zoom in to my strokes and if they're pixely my brain has issues really getting the structure. High Resolution makes it easier for me to not get distracted by minor things.
When it comes to colors I was like: I got Apple Products with those Retina Screens and I wanted to use RGB/32 because that offers more colors and I figured it could look more vivid on said screens.
For DPI: I got no damn clue. An artist I know usually goes with 400, so I picked that too.
Could I theoretically use 100 DPI and upscale it to 400 dpi if needed later ? To reduce strain I mean.

I certainly understand, personally I would recommend continuing to use this same canvas size, but try reducing the DPI to 300 and the Colour Format to RGB/16bit.

If you are not specifically designing content to be displayed on a HDR compatible display once exported, then there is little to no benefit to using 32bit colour for your file.
32 bit colour works using a 'floating point' unbounded colour space, which can require much more computational power to calculate - therefore it's expected that documents using 32bit colour can perform slower than those using 8/18bit.

You will likely encounter further incompatibilities/unexpected colour reproduction when viewing these 32bit documents on non-32bit displays, or when exporting to formats that don't support this colour depth (ie JPEG).

I hope this helps

[Tox]

Oh no worries. for the time being I just draw in the weird resolutions, it's just hobby anyways.

Will do, thanks!

On 9/14/2023 at 1:37 PM, Dan C said:

I certainly understand, personally I would recommend continuing to use this same canvas size, but try reducing the DPI to 300 and the Colour Format to RGB/16bit.

If you are not specifically designing content to be displayed on a HDR compatible display once exported, then there is little to no benefit to using 32bit colour for your file.
32 bit colour works using a 'floating point' unbounded colour space, which can require much more computational power to calculate - therefore it's expected that documents using 32bit colour can perform slower than those using 8/18bit.

You will likely encounter further incompatibilities/unexpected colour reproduction when viewing these 32bit documents on non-32bit displays, or when exporting to formats that don't support this colour depth (ie JPEG).

 

Can I do that in the existing document or do I need to create a new one ? 
That with the 32 Bit sounds very interesting. I should learn more about that

 

[Dan C]

On 9/15/2023 at 8:31 PM, Tox said:

Can I do that in the existing document or do I need to create a new one ? 

With your existing document, you can use Document > Convert Format / ICC Profile... to convert the document from 32bit to 16bit/8bit as required.

You can also use Document > Resize Canvas to adjust the DPI of the document, choosing to resample the layers in your document if you wish.

On 9/15/2023 at 8:31 PM, Tox said:

That with the 32 Bit sounds very interesting. I should learn more about that

You can find some information on 32bit editing in Affinity below, although there is certainly a rabbit-hole of learning when it comes to 32bit image editing due to the hundreds of variables in profiles, displays, HDR, nits, etc -

32-bit HDR editing

Merging to 32-bit HDR

Tone Mapping HDR images

32-bit Preview panel

[Tox]

Thank you!

When it is such a rabbit hole I should probably learn drawing first lol.

[Tox]

Unfortunate update:
I created a Document with 12000 * 6000 pixel with 300 dpi and 16 Bit colouring and have the same issues I have with the document with 400 dpi and 32 bit