Performance Issues

[Wintermote]

@Gusmal

it is indeed the multi-z stuff causing old GPU’s to struggle while multi-z is off testing

@birb

Soro, especially during weather was the biggest example, VFX like particles and colored lighting also ate vram

I know with a deferred rendering pipeline there’s intrinsic issues with alpha-blending and layering textures, and the snow/weather effects having an fps impact is common in deferred rendering, so I asked chatgpt if this same type of issue exists in BYOND:

Alpha-blending many textures on top of each other is computationally expensive in deferred rendering pipelines and comes with a bunch of lighting bugs, and it looks like the same is true for BYOND’s “blitting-based rendering”.

As for multi-z’s impact, iirc there’s a blur effect done on stuff at lower z-levels, and if that’s done with alpha-blending on runtime rather than using pre-made blurred sprites, that would be a cause for worse performance. The game might also be checking every tile to see if it’s supposed to be rendering over a lower z-level despite there not even being any lower z-levels. It’s hard to say without knowing how it works though.

To be more specific to the workarounds chatgpt suggested, you can use alpha-masking and dithering to blend layers rather than alpha-blending. I can’t really comment much on whether there’s actual performance gains to be had here in CM, but any textures that are solid instead of transparent ought to be using alpha-masking and not blending, unless there’s features that require the blending (the lighting probably does).

@Gusmal

After checking it out they did say the code is fine and it is an hardware issue

Saying it’s an “hardware issue” is vague; does he mean BYOND is using something like AVX2 instructions that older CPU’s lack, or does he mean he’s just not optimizing for older hardware?

I’ll say that despite having a 5800x3d, 64gb ram, and a 3060(12gb) I STILL get bad fps performance in CM - mostly when using binoculars or ghost zoom, but sometimes even with the normal view size. I really shouldn’t need even better hardware than this to run a 2D spaceman game above 30fps. The fact I still drop under that with this hardware strongly suggests there are massive performance improvements sitting on the table still. No reason this game shouldn’t be capable of running >120fps at all times with what it’s actually rendering.

IMO the game has serious performance bottlenecks and we shouldn’t just be shrugging and saying “buy a better computer” when someone brings it up.

[Gusmal]

@Wintermote

IMO the game has serious performance bottlenecks and we shouldn’t just be shrugging and saying “buy a better computer” when someone brings it up.

• Well can’t blame them for saying “You should upgrade.” because optimising stuff especially ss13 which I guess is a big noodle code is probably hard and time consuming. Adding to that we are a minority in the playerbase, rest is having no problems with it.

@Wintermote

No reason this game shouldn’t be capable of running >120fps at all times with what it’s actually rendering.

• Nothin’ we can do really like I said previously but you got a point I do get better fps when playing something else which requires more hardware to run, byond is just… weird on that part I guess.

@Wintermote

I really shouldn’t need even better hardware than this to run a 2D spaceman game above 30fps.

• Oh believe me, I have seen and experienced worst… My usual FPS was like 20 or so and it would go down to 10 when you are at the front or FOB if its a long round. Imagine trying to hit someone with that
  The solution I found was to play non-combat roles and bam if you were at shipside you had smooth gameplay. That does not work now because currently even if its lowpop/empty space you get the same ol’ 5 fps treatment.

[apsuaduck (Daut)]

ive had the same issues, that’s why i stopped playing cm, it’s been like this for quite some time and for those reasons i believe the coders not gonna cook any improvements for low-end-gpu guys, and when asking the admins they seem to not know what the problem is, so we are indeed a minority

its over