Construct 2 Slowdowns On Windows 10 (DPI Related?)

Ashley After doing some research with members from the community which experience performance issues with Construct 2 on Windows 10, I've come to the conclusion that "high-dpi scaling" might be at fault.

Just a quick note before we go into more detail, Microsoft decided to drop the legacy option to disable application specific high-dpi scaling and pretty much force enable it now, so I couldn't fully test if it's indeed at fault for all performance related complaints that have been reported over the recent months.

TL;DR: I would appreciate if everyone who'd like to participate in this topic, could refrain from posting raging assumption based conclusions.

As you might already know, Windows 10 more recently decided to only allow users to override the dpi setting and not disable it completely. However I found out that it's possible to set it to "Application Mode", which basically means that C2 has full control over the dpi mode. I assume that C2 has high-dpi support enabled by default, which could be the reason for why users started experiencing performance issues more recently and not before that mentioned update that started forcing high-dpi mode.

What does this all mean and why should you care about any of this?

Simple, with an added option to disable high-dpi as a whole for C2 (despite it's downsides of overall quality), users that experience performance issues could test it out and provide feedback which could lead to the conclusion that high-dpi scaling is indeed at fault for the most recent performance issues with C2 on Win10.

+1

If you mean "Override high DPI scaling" setting on Compatibility tab in C2 shortcut - I tried this and it didn't help.

In fact, I tried all compatibility settings and none of them made any difference.

I'm a bit confused, are we not already able to turn off high-dpi scaling in the settings on our C2 projects ?

This seems to raise more questions than it answers...

Just a quick note before we go into more detail, Microsoft decided to drop the legacy option to disable application specific high-dpi scaling and pretty much force enable it now

Which setting, exactly?

[quote:31cwhx3u]As you might already know, Windows 10 more recently decided to only allow users to override the dpi setting and not disable it completely.

I didn't know that - which setting has changed and how? I still see DPI options in the Compatibility tab of an executable in the latest patched Windows 10.

[quote:31cwhx3u]However I found out that it's possible to set it to "Application Mode", which basically means that C2 has full control over the dpi mode.

C2 should already have full control over the DPI mode. It registers as a "system DPI aware" process, which means it handles the global system DPI setting. This does not cover the more recent support for multi-monitors with differing DPIs, but that seems a fairly niche case.

[quote:31cwhx3u]I assume that C2 has high-dpi support enabled by default, which could be the reason for why users started experiencing performance issues more recently and not before that mentioned update that started forcing high-dpi mode.

C2 has had basic support for high-DPI for as far back as I can remember. There's nothing we've changed on that front for a long time, and C2 should not have been using a compatibility mode, because it is natively system-DPI aware.

[quote:31cwhx3u]Simple, with an added option to disable high-dpi as a whole for C2 (despite it's downsides of overall quality)

This would make the whole UI look blurry. I'm sure the next question would be "how do I make sure the UI looks sharp?" We already worked around the event dialog performance issue by implementing a special setting, and then the next question was "how do I fix the performance issue without using the special setting?", so it seems these kinds of workarounds are not satisfying to users.

[quote:31cwhx3u]users that experience performance issues could test it out and provide feedback which could lead to the conclusion that high-dpi scaling is indeed at fault for the most recent performance issues with C2 on Win10.

What evidence is there that this does cause the performance issue? What measurements have been made with which combinations of settings and how do they compare? I don't see any evidence at all for this right now.

If you mean "Override high DPI scaling" setting on Compatibility tab in C2 shortcut - I tried this and it didn't help.

In fact, I tried all compatibility settings and none of them made any difference.

If that's the case then high-dpi is probably not at fault for the slowdowns. I'd still like to get more feedback from more users before dropping this though.

Thanks for testing it out and providing feedback!

I'm a bit confused, are we not already able to turn off high-dpi scaling in the settings on our C2 projects ?

Yes but this is for Construct 2 itself and as far as I'm aware it makes use of this feature.

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This seems to raise more questions than it answers...

Which setting, exactly?

I didn't know that - which setting has changed and how? ...

Windows 7 + Win10 (before update) / Win10 (after forced dpi update)

I assume that C2 has high-dpi support enabled by default, which could be the reason for why users started experiencing performance issues more recently and not before that mentioned update that started forcing high-dpi mode.

C2 has had basic support for high-DPI for as far back as I can remember. There's nothing we've changed on that front for a long time, and C2 should not have been using a compatibility mode, because it is natively system-DPI aware.

The latest changes were done in r229, assuming that high-dpi is indeed the cause for slowdowns it would make sense for people which experience these issues without having a Win10 system with the latest updates.

This would make the whole UI look blurry. I'm sure the next question would be "how do I make sure the UI looks sharp?"

Could you please stop being "trolly" and stop putting words in my mouth. I'm trying to have an honest and polite conversation which hopefully ends up in finding a solution to this problem. (I know you've had your fair share of bad experiences but I'm just trying to help by providing possible causes for this impactful issue.)

We already worked around the event dialog performance issue by implementing a special setting, and then the next question was "how do I fix the performance issue without using the special setting?", so it seems these kinds of workarounds are not satisfying to users.

This isn't really a request for a long-term settings option to degrade the quality of Construct 2, it would a temporally (beta) option in order to maybe find the cause for slowdowns and help you out to narrow it down and fix it. Unless of course you've found the cause already, in that case I'd really appreciate a heads up about it!

What evidence is there that this does cause the performance issue? What measurements have been made with which combinations of settings and how do they compare? I don't see any evidence at all for this right now.

That's the issue, as far as I know Win10 doesn't allow to disable high-dpi in the properties anymore (at least the community members I've asked couldn't find a way to disable it completly). Based on a more recent report about high-dpi and performance problems and the before mentioned updates in r229, which exactly fit the the affected parts of Construct 2, I thought this might be the fault of high-dpi. High-dpi is known for causing bad performance even in exported C2 games which lead to my assumption based conclusion that it might be at fault.

> This would make the whole UI look blurry. I'm sure the next question would be "how do I make sure the UI looks sharp?"

>

Could you please stop being "trolly" and stop putting words in my mouth. I'm trying to have an honest and polite conversation which hopefully ends up in finding a solution to this problem. (I know you've had your fair share of bad experiences but I'm just trying to help by providing possible causes for this impactful issue.)

I'm sorry, I don't mean to troll you, I'm just describing exactly what happened last time we added a performance workaround. We add a workaround, then someone immediately asks to fix it without the workaround. ¯\_(?)_/¯

[quote:33a7xihx]

What evidence is there that this does cause the performance issue? What measurements have been made with which combinations of settings and how do they compare? I don't see any evidence at all for this right now.

That's the issue, as far as I know Win10 doesn't allow to disable high-dpi in the properties anymore (at least the community members I've asked couldn't find a way to disable it completly). Based on a more recent report about high-dpi and performance problems and the before mentioned updates in r229, which exactly fit the the affected parts of Construct 2, I thought this might be the fault of high-dpi.

So, just to be clear, you don't have performance measurements to back this up?

[quote:33a7xihx]High-dpi is known for causing bad performance even in exported C2 games which lead to my assumption based conclusion that it might be at fault.

I've never seen or heard any such cases of high-DPI causing performance issues in C2 games, unless it's due to GPU bandwidth limits. The option to disable high-dpi mode in the runtime is essentially a variant of "low quality" fullscreen mode. I don't think there's any kind of parallel to the editor there, editing software does not usually come close to GPU fillrate limits, it's entirely different to game rendering.

I'm sorry, I don't mean to troll you, I'm just describing exactly what happened last time we added a performance workaround. We add a workaround, then someone immediately asks to fix it without the workaround. ¯\_(?)_/¯

No problem. Although I can understand that people would request a quick fix because they might not have the time to wait for the whole process of isolating the bug and fixing it. Sadly this doesn't seem to be an easy one to fix.

So, just to be clear, you don't have performance measurements to back this up?

I've never seen or heard any such cases of high-DPI causing performance issues in C2 games, unless it's due to GPU bandwidth limits. The option to disable high-dpi mode in the runtime is essentially a variant of "low quality" fullscreen mode. I don't think there's any kind of parallel to the editor there, editing software does not usually come close to GPU fillrate limits, it's entirely different to game rendering.

You're right, I'm just assuming that it might be at fault and the problem is that I wasn't and am not able to test this out. I don't own a Win10 system (yet) and I don't want to cause any damage to the systems of the people that helped me out with testing so far, by manipulating the registry or whatever is necessary in order to force disable it for reproduction.

The high-dpi setting in exported games only seem to affect some systems, not all of them. All I know is that disabling it helped those systems to run the game well. It's always difficult to narrow down the main cause for performance issues but I guess the slight quality improvements when using high-dpi were too much to handle for those systems.

On a different note, I've recently received a PM by a community member and Windows update "kb4087256" seems to have fixed all of his slowdown problems. He's provided a screenshot with the updates that probably fixed it and after looking up the changes of each individual update on Microsoft's support thread, "kb4087256" seems to be the one which might be the solution to all of this. It would be great if you and generally everyone without slowdown issues could temporally remove those marked updates and test if any slowdowns occurs. If the updates are missing, I'd appreciate installing them and providing feedback if it fixed the slowdown issues.