Screen Melt Way Too Slow
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Contrary to popular belief, we are not all-knowing-all-seeing magical beings!
If you want help you're going to have to provide lots of info. Like what is your hardware, what is your operating system, what version of GZDoom/LZDoom/whatever you're using, what mods you're loading, how you're loading it, what you've already tried for fixing the problem, and anything else that is even remotely relevant to the problem.
We can't magically figure out what it is if you're going to be vague, and if we feel like you're just wasting our time with guessing games we will act like that's what you're really doing and won't help you.
Contrary to popular belief, we are not all-knowing-all-seeing magical beings!
If you want help you're going to have to provide lots of info. Like what is your hardware, what is your operating system, what version of GZDoom/LZDoom/whatever you're using, what mods you're loading, how you're loading it, what you've already tried for fixing the problem, and anything else that is even remotely relevant to the problem.
We can't magically figure out what it is if you're going to be vague, and if we feel like you're just wasting our time with guessing games we will act like that's what you're really doing and won't help you.
- Graf Zahl
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Re: Screen Melt Way Too Slow
It's something directly affecting performance settings, so, yes that is possible. Do you use VSync or other frame rate limiting options?
I'll run some tests myself at home.
I'll run some tests myself at home.
- Redneckerz
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Re: Screen Melt Way Too Slow
Given you have this issue, but also this hardware, the bug and eventual fix is just a positive byeffect for GZDoom.Starisma1 wrote:So I wonder will this bug be fixed in 4.5?
For you, however, its still recommended to use LZDoom, because Intel Baytrail graphics is beyond slow.
- sinisterseed
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Re: Screen Melt Way Too Slow
Framerate set to Unlimited, but the default 200 makes no difference.Graf Zahl wrote:It's something directly affecting performance settings, so, yes that is possible. Do you use VSync or other frame rate limiting options?
I'll run some tests myself at home.
Naturally using VSync

- Graf Zahl
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Re: Screen Melt Way Too Slow
For me (Geforce 1060) this makes no difference at all. Weird.
- sinisterseed
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Re: Screen Melt Way Too Slow
And I might now why.
I think none of your are having issues because you're all too fast. This may be similar to the tearing videos in Blood, which only us with slower machines used to experience, apparently.
I think none of your are having issues because you're all too fast. This may be similar to the tearing videos in Blood, which only us with slower machines used to experience, apparently.
- drfrag
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Re: Screen Melt Way Too Slow
The original commit when it was added in may 2018 says:
For me it was already false dunno why and makes no difference.
Code: Select all
- added CVAR to disable WGL_EXT_swap_control_tear.
At least on faster NVidia hardware, setting this to false and gl_finishbeforeswap to true gives a better experience because it reduces screen tearing - but the same setting will reduce frame rate quite dramatically on Intel and can cause bad stalls on some older GPUs when rendering camera textures.
- sinisterseed
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Re: Screen Melt Way Too Slow
Hm, no idea what's up with finishbeforeswap, haven't checked that one.
- Graf Zahl
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Re: Screen Melt Way Too Slow
drfrag wrote:The original commit when it was added in may 2018 says:For me it was already false dunno why and makes no difference.Code: Select all
- added CVAR to disable WGL_EXT_swap_control_tear. At least on faster NVidia hardware, setting this to false and gl_finishbeforeswap to true gives a better experience because it reduces screen tearing - but the same setting will reduce frame rate quite dramatically on Intel and can cause bad stalls on some older GPUs when rendering camera textures.
Yes, I know. Note the word "Camera textures" and "Intel". Definitely not "melting".
Back then I was using a Geforce 550Ti on which it caused major issues with camera textures. But it still gave the best experience because it avoids frame drops and has no tearing.
I find tearing the most distracting render artifact out there.
sinisterseed wrote:Hm, no idea what's up with finishbeforeswap, haven't checked that one.
It shuffles around some operations on a screen swap. The results are very hardware dependent.
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Re: Screen Melt Way Too Slow
I'll later if I get on my PC again before I go to sleep if it changes anything, I expect nothing but who knows.
- sinisterseed
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Re: Screen Melt Way Too Slow
Alright, so gl_finishbeforeswap set to "true" also fixes the melt screen crawl, so it's either that, or setting gl_control_tear to "true" to fix it for some of us, looks like.
- Graf Zahl
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Re: Screen Melt Way Too Slow
I am actually a bit puzzled. The melt effect is as cheap as they come - after reading the images into two textures all it does is render 320 strips of image each frame.
- sinisterseed
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Re: Screen Melt Way Too Slow
I can only tell what I see, and this is it, with gl_control_tear set to false, setting gl_finishbeforeswap to true fixes the crawl here
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Re: Screen Melt Way Too Slow
alright i just installed the newest version of LZDoom so ill see if theres a screen melt bug thereRedneckerz wrote:Given you have this issue, but also this hardware, the bug and eventual fix is just a positive byeffect for GZDoom.Starisma1 wrote:So I wonder will this bug be fixed in 4.5?
For you, however, its still recommended to use LZDoom, because Intel Baytrail graphics is beyond slow.
Re: Screen Melt Way Too Slow
Update: I tried out gzdoom 4.5 and i no longer have a slow screen melt so i guess 4.4 must of been buggy for my system because 4.5 completely fixed the bug even though my computer has slow hardware
- sinisterseed
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Re: Screen Melt Way Too Slow
Since this is still open.
As of g51adcd45e I am no longer experiencing the melt crawl either, it's back to normal.
As of g51adcd45e I am no longer experiencing the melt crawl either, it's back to normal.