Thank you! (Dithering)

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vorob
Posts: 41
Joined: Wed 03 Aug, 2016 7:28 am

Thank you! (Dithering)

Post by vorob » Wed 03 Aug, 2016 9:14 pm

I just have no words to say :) That’s just miracle. Thank you guys, to all of you.

While today we have many ways to run 3dfx-era games (like using nglide), it’s still just wrappers, not the emulation. And with this “interlayer” between game requests and new hardware we are getting some changes in rendering…

With PCem, from what I see, we are getting the same exact look, that we had over 16-20 years ago. With dithering!!!

Take a look, Quake II launched in 3dfx mode via nglide:
https://pp.vk.me/c631926/v631926184/3e7 ... clA-K8.jpg

And this one lunched in PCem:
https://pp.vk.me/c631926/v631926184/3e7 ... -PGhG8.jpg

PCem one is the way it meant to be played :)

Anyway, I’ve tested following games:

GTA
GTA 2
Quake (https://youtu.be/7xXI6fvTUhg)
Quake II (https://youtu.be/SPsN8iIU_t8)
Thief The Dark Project
System Shock 2
Pyl (Polish shooter 1999) (https://youtu.be/CJt60vDX_AQ)
Tomb Raider

And they worked without a single issue. Sometime performance may be far from good, but most important, its making games work and look like on real VooDoo card. Without artifacts.

Only one game wasn’t working for me:
Requiem Avenging Angel
And I’ll create special thread about this :)

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leilei
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Joined: Fri 25 Apr, 2014 4:47 pm

Re: Thank you! (Dithering)

Post by leilei » Wed 03 Aug, 2016 10:10 pm

A real voodoo wouldn't expose the dithering as pristine and intact in the screenshot though, as it had a undithering filter on the DAC which gave 3dfx their characteristically blurry/waxy look. You'd only usually see those unfiltered, dithered pixels in windowed mode on a Banshee/V3/V4/V5, or screenshot dumps from games (except for those using 3dfx's MiniGL in which that will filter them by software)

There is a feedback artifact with the filter in the v11 release however. I've fixed that since (And created another line artifact on the way there :( )

vorob
Posts: 41
Joined: Wed 03 Aug, 2016 7:28 am

Re: Thank you! (Dithering)

Post by vorob » Wed 03 Aug, 2016 10:28 pm

leilei wrote:A real voodoo wouldn't expose the dithering as pristine and intact in the screenshot though, as it had a undithering filter on the DAC which gave 3dfx their characteristically blurry/waxy look. You'd only usually see those unfiltered, dithered pixels in windowed mode on a Banshee/V3/V4/V5, or screenshot dumps from games (except for those using 3dfx's MiniGL in which that will filter them by software)

There is a feedback artifact with the filter in the v11 release however. I've fixed that since (And created another line artifact on the way there :( )
Well,

1. Filter off
https://pp.vk.me/c631926/v631926184/3ea ... wwhrCg.jpg
2. Filter on
https://pp.vk.me/c631926/v631926184/3ea ... GEsaDU.jpg

So, you are saying that #2 is closer to what people saw back then?

Anyway, we have dithering here, thing completely lost on now-days cards and nglide... So, its better then nothing :)

vorob
Posts: 41
Joined: Wed 03 Aug, 2016 7:28 am

Re: Thank you! (Dithering)

Post by vorob » Wed 03 Aug, 2016 10:31 pm

P.s. so on other cards of this time, in 16bit applications, dithering also existed, but was displayed as is, without filtering?)

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leilei
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Re: Thank you! (Dithering)

Post by leilei » Wed 03 Aug, 2016 10:37 pm

That's right. 3dfx was also once in an ubiquitous state that 16-bit dithering/grain was a common complaint on anything that wasn't a 3dfx card (was well as the default gamma being kicked up to 1.3/1.7 on 3dfx, causing its rivals to be "too dark" when they're actually correct).

The filter was definitely coded in for more hardware preservation/accuracy, and the filter is one of the most overlooked parts of 3dfx emulation. There wasn't any effort for it in real-time until I wrote a shader in 2013


There is at least one other non-3dfx card that features 16-bit undithering filter however, and it's the PowerVR KYRO series- its technique is close to Voodoo3's "22-bit" 2x2 box filter

vorob
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Joined: Wed 03 Aug, 2016 7:28 am

Re: Thank you! (Dithering)

Post by vorob » Thu 04 Aug, 2016 5:37 am

Big big thank you on all these details. Really interesting. Wonder how close your current filter to un-dithering thing in real voodoo. You are saying PCem obvious "line effect" is a temporary thing?

And about this
default gamma being kicked up to 1.3/1.7 on 3dfx, causing its rivals to be "too dark" when they're actually correct
Noticed this when i was comparing nglide vs default ogl vs pcem:

https://pp.vk.me/c631926/v631926184/3eb ... PUr3f8.jpg
https://pp.vk.me/c631926/v631926184/3eb ... hYJxo0.jpg
https://pp.vk.me/c631926/v631926184/3eb ... hoWEM0.jpg

OGL is extremely dark, hard to play. I wonder which one is the proper from developers perspective? How they planned this game to be played? Dark or well lit?

RetroGIG94
Posts: 92
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Re: Thank you! (Dithering)

Post by RetroGIG94 » Thu 04 Aug, 2016 5:51 am

I wonder if anyone can try Lego creator with this "interlayer"?

vorob
Posts: 41
Joined: Wed 03 Aug, 2016 7:28 am

Re: Thank you! (Dithering)

Post by vorob » Thu 04 Aug, 2016 5:55 am

RetroGIG94 wrote:I wonder if anyone can try Lego creator with this "interlayer"?
Well, nglide will be "interlayer" and PCem is full scale emulator of holy voodoo card :)

But i'll check this game today, already downloading it...

RetroGIG94
Posts: 92
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Re: Thank you! (Dithering)

Post by RetroGIG94 » Thu 04 Aug, 2016 2:35 pm

Also where you using Nglide inside the Windows 9x OS or outside the PCem emulator?

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ender
Posts: 51
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Re: Thank you! (Dithering)

Post by ender » Thu 04 Aug, 2016 3:27 pm

nglide is meant to be installed on modern systems to allow them to run Glide games. You can't use it with PCem in any form.

vorob
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Re: Thank you! (Dithering)

Post by vorob » Thu 04 Aug, 2016 3:38 pm

RetroGIG94 wrote:Also where you using Nglide inside the Windows 9x OS or outside the PCem emulator?
You are missing the point. Nglide is for windows 7-8-10, wrapper which allows to launch glide games, but with modern rendering (no dithering). Also it won't help for really old glide games, dos era or too old windows games cause the maybe not working for many reasons...

PCem emulated voodoo card inside its system. Its like virtual machine. No need to install nglide there.

RetroGIG94
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Re: Thank you! (Dithering)

Post by RetroGIG94 » Thu 04 Aug, 2016 6:53 pm

So vorob did you tried Lego creator yet?

vorob
Posts: 41
Joined: Wed 03 Aug, 2016 7:28 am

Re: Thank you! (Dithering)

Post by vorob » Thu 04 Aug, 2016 9:20 pm

RetroGIG94 wrote:So vorob did you tried Lego creator yet?
Yep, its working. But looks like it doesn't work with 3dfx. Instead it works in software mode and performance is unplayable.

RetroGIG94
Posts: 92
Joined: Wed 30 Mar, 2016 4:09 am

Re: Thank you! (Dithering)

Post by RetroGIG94 » Thu 04 Aug, 2016 10:52 pm

Well if you use the Mach64gx it can make the game use the Voodoo card Omarsis81 knows how to fix it.

RetroGIG94
Posts: 92
Joined: Wed 30 Mar, 2016 4:09 am

Re: Thank you! (Dithering)

Post by RetroGIG94 » Sun 07 Aug, 2016 7:22 am

How good is the framerate for some games?

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