Texture filtering default discussion

[Enjay]

Yeah, the menus have been a problem for a long time. At its core, the real difficulty is that there are a LOT of options. The simplified menu was meant to help with that but I just find it gets in the way and hides stuff that I want. Of course, I am familiar with what should be there and what isn't when the simple menu is active. It's another default setting that I change. I have made a few stand alone games and (I think) been able to simplify the menu to an acceptable layout. Of course, in those circumstances, a lot of the options are irrelevant and can simply be omitted. One user once said "can you just add a menu called 'crap I use all the time'". So, I asked him what he used all the time, took an educated guess at a few other likely things and made a menu called exactly that.

There has been a change in the GZDoom menus pretty recently. The latest GitBuilds and UZDoom have a different options menu setup versus GZDoom 4.14.2. Is it better? Personally, I don't find it so, but I don't find it any worse either - just different.

I would kind of hope that a seasoned game streamer was familiar with the concept of the console, it's not that unusual for there to be one, but you never know. The biggest thing that changes is how to access it - but the same key as ZDoom uses is very common. Like I said though, that comment was mostly a joke.

[Enjay]

What you had was a broken monitor. VGA monitors were designed for readable text in an office building, they weren't TVs, and as such 320x200 was double scanned to a higher resolution. There's minimal colour bleeding on a properly calibrated CRT at that resolution as a result.

No, I didn't. What I had was access to many monitors over the peak Dooming years, attached to the many computers that I played Doom on - from an (at the time) decent spec gaming PC, to the "I can barely run this" machines in some of my work locations. I set up LAN games in schools and offices, had a permanent multiplayer setup in my house and ran deathmatch sessions at several gaming cons. I know what Doom looked like on a wide range of CRT monitors.

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My kids playing multi-player (admittedly probably late 90s, and ZDoom) on their multi-player setup on just two of the several computers that we had at the time.

My final CRT monitor (many years ago now) was a relatively big, bright, well calibrated monitor (yes, I am one of those weird people who actually change their monitor settings and run calibrations on them) and I went to significant lengths to compare it to my first flatscreens. Overall, it was less bright and less crisp (even though it had a comparable resolution capability). It wasn't all bad though. I thought that it felt generally warmer, gentler and "nicer" somehow in a vinyl versus CDs kind of way. Modern flat-screens are very different in character to CRTs.

I also don't really think you can expect the average gamer in 1993-1996 to have a properly calibrated CRT (not that you said they did). Yes, perhaps the game artists would probably have had, but they also knew what the general public would be playing their games on - and for the vast majority, it wasn't properly calibrated high quality monitors. Let's not forget, at the time, computers were comparatively expensive and still regarded as a luxury by many. So, that was the environment that the game was being sent out into. That was the hardware they knew it was going to be played on. No one considered that it would be getting played on much more sophisticated hardware over three decades later.

It's also worth acknowledging that a lot of game art from the time actually isn't that good - and I (sacrilege warning) would include Doom in that. There are stray pixels, missing bits, things that look different from one angle to the next, things that didn't get translated to the palette very well and weren't touched up and so on (and some other contemporary games are far, far worse). Perhaps it was the rush to get the job done. Perhaps it was because there were hundreds of images to make. Perhaps it was the limitations of trying to make something look discernable at only 56 pixels tall. And, maybe, it was because they knew how well the images would be displayed on the average user's monitor and knew where the "good enough" line was.

One thing is for certain - very few, if any, users in 1993 were able to see Doom with the crispness that modern hardware allows, and I think that is relevant to the many discussions that the Doom community (and other retro gaming communities) have about how their games are "meant to look".

[edward850]

That doesn't reflect my experience at all, and certainly never saw anyone with the same problem. Sorry but I cannot possibly agree with your perspective. It just sounds like you had broken monitors to me.
Also if your argument is "we should have texture filtering because CRTs", then that's even more off base because texture filtering doesn't even come close to emulating that given the linear algorithm and the transparencies on sprites wouldn't even match the borders, they look nothing alike. If you think U/G/Zdoom or whatever should be emulating the look of a CRT as the default, then what you should be arguing for is a VGA CRT shader. Take the one from DOS Box Staging, make that the default.

[Enjay]

All of them? Like over 100 of them?
It was definitely a thing that was discussed all the time as people were transitioning from CRTs to flatscreens. The differences, pros and cons were well debated. Flatscreens (of the various types are) generally agreed to be brighter, sharper and crisper but more stark with less subtlety about colour transition and (initially at least) less accurate colours and poorer black display than a CRT. CRTs are acknowledged as generally less bright and sharp and having distortion due to the curved screen, poor ones may have some flicker. The way they display images by drawing lines one by one also comes into play too versus the simultaneous display of pixels on modern hardware. But they do have advantages like better viewing angles (early flatscreens were terrible for that) and being better at showing fast moving things and they didn't have fixed resolutions in the same way as flatscreens do.

Hang on, let's see what Google has to say: Query "visual differences between flatscreens and CRTs"

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CRT (Cathode Ray Tube)
Curved or "flat" screen that is actually a convex shape, causing a slight bulge
Very bulky and heavy due to the electron gun and funnel-like tube behind the screen
An electron beam draws each frame line by line
Flexible resolution, can be scaled to different resolutions
Can look softer, especially with modern content, but often preferred for older content where the line-based image looks more natural
Can have more intense colors and deep blacks, as pixels are turned off completely for black
Can exhibit noticeable flicker, especially at lower refresh rates
Excellent, with minimal change in picture quality from any angle
Superior motion handling due to the way images are drawn

Flat Screen (LCD, LED, OLED)
Perfectly flat
Slim and lightweight, allowing for wall-mounting
A grid of pixels is lit simultaneously
Fixed resolution, meaning a set number of pixels
Capable of very sharp and crisp images
Colors can be very vibrant, but black levels are not as deep as a CRT's
Flicker-free display
Can have a "sweet spot" where viewing angles are restricted, though modern screens have improved this significantly
Modern screens have improved motion handling, but older models may have more motion blur

It's not just me.

Edit: I just found someone saying that CRTs are better for retro gaming because they have "natural anti aliasing built in."

[edward850]

Again, people confuse VGA monitors and TVs all the time, but they produce very different picture quality.

You also haven't responded to the rest of my message about what you're arguing for isn't even the same thing. You are arguing for screenspace filtering which is what a CRT would (hypothetically) do in this example, not sprite filtering which is what GZDoom's texture filtering actually is, and what you should actually be arguing for is a VGA screenspace shader. You aren't even talking about the right things.

Edit: Also:

Yes, perhaps the game artists would probably have had, but they also knew what the general public would be playing their games on

I actually talked to Kevin Cloud about texture filtering twice. It's fairly safe to say we know Quake 1 wasn't supposed to have it, and Quake 2 was supposed to have it. He's retired so I can't ask him about Doom directly (unless I see him at QuakeCon again), but given he was around while we were doing Doom64 and Unity Doom's art style never came up (that project was being done at the same time), and nothing about filtering was discussed in regards to Doom + DoomII, I'm confident that despite how screens may have looked or not, what GZDoom is currently doing with texture filtering wasn't his intent.

[bimshwel]

I have also seen the argument that you "need" to get period authentic monitors so that dithering on sega genesis games looks correct. I still like being able to see pixel edges, even if it is less period accurate, but I figured that was just particular to me. I don't like pixelized blending in general. I don't even like it in doom 64 where that IS the authentic appearance.

[Enjay]

Again, people confuse VGA monitors and TVs all the time, but they produce very different picture quality.

You also haven't responded to the rest of my message about what you're arguing for isn't even the same thing. You are arguing for screenspace filtering which is what a CRT would (hypothetically) do in this example, not sprite filtering which is what GZDoom's texture filtering actually is, and what you should actually be arguing for is a VGA screenspace shader. You aren't even talking about the right things.

You are correct. I'm not talking about those things deliberately. I think you've maybe picked up on an unintended implication from what I've been saying. I'm not even talking about texture filtering at the moment. I'm saying that when people in this community and others discuss what looks "right" for a retro game, they often don't talk about a very significant component - the appearance of the image on modern monitors versus what it looked like on a monitor from the time. They get very tied up with how Doom was "meant to be", but it certainly wasn't "meant to be" shown on a high resolution, bright, vivid, 8K widescreen monitor using technology that was years away from even being invented in 1993. The target was a low-res CRT monitor running at 320x200 in 256 colours - bleeding edge at the time because some PC games still came with EGA and even CGA options (and a sound card was an absolute luxury). It's nice to be able to view Doom on a modern monitor, but that's not what it was designed for. Surely there's nothing controversial in that?

I'm not arguing for anything. I didn't even think I was arguing at all. In fact, although I have stated my preference for filtered textures, I have tried to avoid arguing for them or against unfiltered ones throughout this thread, because that's not what the thread was about. It wasn't about what's better or even peoples' preferences. It was about why are people so invested in the default choice - and that' pretty much been answered.

In my more recent posts, however, I was just trying to make the point that a 1993 monitor shows a very different image to a 2025 one, and I was trying to characterise some of those differences. I'm not arguing for filtering, and I'm not dismissing anything either. Personally, I am not interested in emulating the CRT look in my Doom (much as I loved my final CRT, hung on to it for as long as possible and felt that my first flatscreen was a definite downgrade as far as visual fidelity was concerned). But that's not what I am talking about. I'm saying that there is a difference in the capability and nature of what a 1993 monitor can show versus new monitors. That's it - and surely that's undeniable?

The kind of monitor that a typical PC user was using in 1993-96 was incapable of the large, bright, sharp, vivid, high-definition images that we are using to look at Doom today by default. Doom was not made for modern monitors. It was made for what was available in 1993 and what 1993 monitors showed was very different to what a modern monitor shows.

That's it. That's all I'm saying. So, by extension, talking about what is "right" for Doom and not talking about the hardware comparisons (which is what usually happens) is missing out a major part of the discussion. People talk about filtering vs not filtering, banded lighting vs smooth lighting, paletted vs true colour and so on but if the user has a modern widescreen, bright, flatscreen monitor (as most do), none of it looks like it did on a 1993 monitor.

It was you who said that one of the problems with texture filtering was that it's not what the art was designed for. I agree, and I've never said otherwise. That's not what I'm talking about at the moment. I'm saying that nothing about a modern monitor and how most people are looking at Doom today is what Doom was designed for either.


As a side point, I know how much better a CRT monitor was than a CRT TV. A decent VGA monitor was way, way better than a TV for computer graphics: brighter, crisper, much better defined. Having run an Amiga 500 on a TV until getting a monitor for it, I have seen the difference on the same computer. It was night and day (and the Amiga was generally displayed on a TV by most users and even came with a TV adaptor out of the box).

Edit: Also:

Yes, perhaps the game artists would probably have had, but they also knew what the general public would be playing their games on

I actually talked to Kevin Cloud about texture filtering twice. It's fairly safe to say we know Quake 1 wasn't supposed to have it, and Quake 2 was supposed to have it. He's retired so I can't ask him about Doom directly (unless I see him at QuakeCon again), but given he was around while we were doing Doom64 and Unity Doom's art style never came up (that project was being done at the same time), and nothing about filtering was discussed in regards to Doom + DoomII, I'm confident that despite how screens may have looked or not, what GZDoom is currently doing with texture filtering wasn't his intent.

That's very cool. It must be great to have had that experience and insight from one of the OG game artists. Very cool, very lucky. To be clear - there is no sarcasm there at all. I genuinely mean it.

I hope you get from my answer to the rest of your post that I never said or expected Doom to be aimed at a texture filtering environment, or that texture filtering accurately emulates a 1993 monitor (it doesn't - not in the slightest, and I never even thought that was the point of it). All I was saying is that the target hardware was very different to what it is being viewed on today, but despite that very clear difference, it rarely seems to come up as part of the discussion.

[Enjay]

I have also seen the argument that you "need" to get period authentic monitors so that dithering on sega genesis games looks correct. I still like being able to see pixel edges, even if it is less period accurate, but I figured that was just particular to me. I don't like pixelized blending in general. I don't even like it in doom 64 where that IS the authentic appearance.

I think one of the biggest problems with people using period authentic monitors is the commitment that it takes. You have to source one, set it up, run a machine aimed at it. Unless you are a very dedicated enthusiast, that's way too much effort, expense and inconvenience. So, it's totally understandable that very few people do it.

You'll maybe laugh at this, but one of the problems I have with Doom64 is its blurry appearance. Having said that I prefer filtered textures, I always found the appearance of Doom64 just too blurry. Part of it is the art style - despite being higher resolution sprites, they look like bigger images that have been scaled down in whatever graphic program was used with antialiasing. The added grainy grunge on the textures looks odd to me too. Another part of it is that, for a long time, I only ever saw it on a TV and (as discussed) that really doesn't do the game any favours. I do like the modern kex port though. I think it gets the balance right when presenting the game resources. I also quite liked Kaiser's original Doom64 EX too. Of course, seeing both of those on a PC monitor helps.

[bimshwel]

Everything on the n64 was too blurry and i don't know how much of that was deliberate, since at least in doom 64 the blur is applied diagonally (quite apparent from the fences right beside the start of the first level) and sprites always look creased in the middle. I remember nintendo power magazine emphasizing how there was no pixelization! Maybe someone somewhere in the corporate chain mandated whatever level of over-blending would accomplish that. I was not incredibly surprised years later to compare the raw doom64 sprites to the ones from regular doom and see that they're only just SLIGHTLY larger (scale .75 seemed to work in zdoom), even though promotional imagery showed monsters at substantially higher resolution. The low resolution in-game presumably was due to storage issues on the cartridge, or maybe the system would just choke to have too many huge graphics at the same time. And I vaguely recall reading that the original 3d models no longer exist to re-export but that might have been the excuse for scenery in the final fantasy 9 "remaster" and I got them confused.

[Enjay]

While I like Doom64, and I totally get why many people rate it very highly (even as the best Doom), it's always been Doom's weird cousin to me. I'm not sure what it is. I dunno, it's almost like it was trying too hard with the (admittedly excellent) ambient music by Aubrey Hodges, the muddy echoey sounds (which again are actually good - I actually used the PSX versions in one of my releases), the very dark levels, the change to more "severe" (if that's the right word) imagery in terms of symbols on the walls and general prop design, the grungy textures and, of course, the monster designs. None of these things are bad - many are really quite good - but the overall package just feels like I want say to D64 "OK, edgelord, sit down before you hurt yourself."

I also find some of the monster designs are a curious combination of over-the-top and weirdly cute. Take the demon, for example, bigger, badder, lurching at you from the darkness with its claws at the ready but it's also got that big goofy grin and almost looks like it's hugging you during its attack. The cacodemon - also with its big goofy grin. I know the original does too, but (to me) the D64 one is more cartoonish in style with its big googly eye and stubby little arms with chains hanging off them.

The baron/hell knight, on the other hand might be OK but whatever process they used to make the sprites made them so muddy that it's kind of hard to tell exactly how they are meant to look at times. That problem affects many of the sprites, but the barons are possibly the worst. I'd actually really like to see some original concept art or the original models (if they hadn't been lost) so that I could go "ahh! that's what they are meant to be like."*

Then, in contrast, you have the pain elemental which is some sort of bizarre, corrupt, two mouthed eldritch horror that has biology unlike pretty much anything else in the game and is unrecognisable as a type of organism that most people are familiar with (and I actually mean that mostly in a good way).

It's still a great game, and I do like it when someone puts their own stamp on something but... I dunno. Like I said, I just get left with this weird feeling of it trying too hard.


*As a total aside, I've never really been able to figure out properly what the faces of the Duke Nukem 3D base lower-tier enemies are really meant to look like, and I've seen hi-res sprites and 3D models, but the original sprites in particular have always been confusing to me.

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GoofBall1.png (6.26 KiB) Viewed 137 times

I don't know why but my brain just sort of short-circuits when I look at them. I think, maybe, the very bright reflection on to of the head draws my attention away from the eyes and somehow makes me think they eyes are not where they actually are... or something. But even the face on something much more detailed like this I... I dunno. It just confuses me somehow.

[phantombeta]

since at least in doom 64 the blur is applied diagonally (quite apparent from the fences right beside the start of the first level) and sprites always look creased in the middle.

It's just how filtering works on the N64, they cheaped out on the filtering for performance, so filtering just takes 3 pixels in a triangle. (normal linear/bilinear filtering like done on computer GPUs and modern consoles takes the 4 closest pixels in a square)
Zelda actually makes use of this "on purpose" in some textures to make smoother lines... But it only works with the texture placed in one direction, in the other it looks weird.

The low resolution in-game presumably was due to storage issues on the cartridge, or maybe the system would just choke to have too many huge graphics at the same time.

It's probably a combination of both, the N64 had a very pitiful 4KB of texture memory, and the main system memory (which was shared with the GPU for things other than textures) was pretty slow, and you already have to shuffle textures between system and texture memory.
This also puts a very tight limit on the maximum resolution of a single texture: a single 8-bit 64x64 texture already takes up 4KB!

*As a total aside, I've never really been able to figure out properly what the faces of the Duke Nukem 3D base lower-tier enemies are really meant to look like, and I've seen hi-res sprites and 3D models, but the original sprites in particular have always been confusing to me.

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GoofBall1.png

I don't know why but my brain just sort of short-circuits when I look at them. I think, maybe, the very bright reflection on to of the head draws my attention away from the eyes and somehow makes me think they eyes are not where they actually are... or something. But even the face on something much more detailed like this I... I dunno. It just confuses me somehow.

It looks kinda like some kinda weird snake head to me :P

[bimshwel]

I was always obsessive compulsive so what bothered me, apart from the triangular blending was that hellknights and barons would gladly assault each other rather than cooperating and you can see them switch hands mid-attack if you happen to be run-dodging around them, and then there are only two zombie types who are 98% identical visually, so that if the developers were looking to save on memory they might as well have just used the same sprites for both and made a chaingun zombie. and then getting the laser properly powered up is like gold chocobo levels of arcane. my younger brother always liked doom 64 better than regular doom --i know HE has the newer version on switch or whatever--, but that might just be because he likes using a gamepad and we never had one for the computer back when we shared one. Also the cheatier monsters aren't present at all, and he was known to even accuse super mario world of cheating. The playstation version at least managed wimpier revenants occasionally, and a few spiderminds at the end though alone and in a dumb place where they shoot each other.

I can't claim to be bothered by inadvertent "cute"ness however since over time I came to see most of the doom monsters as amusing and pleasant sights, like old friends that I just happen to greet by blowing them up. Duke Nukem I failed to latch on to in a big way and never finished but i do find the lower ranked aliens similarly more silly than sinister, whatever they are supposed to look like.

[Chris]

Another part of the blurriness on the N64 was the anti-aliasing and other rendering features it had. Here's a video that really goes into depth on why the system's graphics looked as blurry as they did, and how it can look with various features on and off: https://www.youtube.com/watch?v=BA_HMsznNKg

In my view re: how the game was meant to look, even if we ignore resolution and crt vs flatscreen, I think another element being overlooked is color depth. There is definitely a different look and feel to the lighting when it can dim individual color components with 256 levels each, as opposed to needing to match to 256 colors total. If you're that concerned with how it was meant to look, why are you using the hardware renderer at all, rather than the software renderer that's still there and looks much closer to how it originally did? I remember when hardware accelerated Doom renderers were starting to become a thing, and bi/trilinear filtering was one of the big features to avoid the excessive pixelation, along with true color rendering (or at least 15/16-bit color if you didn't have the luxury of 24/32-bit color) to help avoid the excessive color banding and improve various transparency effects (more of a Heretic/Hexen thing than Doom, but it still made it look better/different). I remember even wishing some port could add bilinear filtering to the software renderer when I didn't have a gfx card for OpenGL support yet, and there was a port that did (some version of Boom, I think?) but the performance tanked because of it. I can for sure understand some/many people having a preference for the original look of the game, but the hardware renderer is a fundamentally different look by design, where the texture filtering is just one of many elements at play. With the amount of work necessary to make the hardware renderer appear closer to the software renderer, why not just use the software renderer?

[Enjay]

Thanks for the link. Some interesting stuff there. I now know much more about the inner working of the N64 than I ever thought I would want to.

I certainly agree that colour depth is also something that gets missed out of the discussion (I mentioned it very tangentially in passing in one of my posts).

If you're that concerned with how it was meant to look, why are you using the hardware renderer at all, rather than the software renderer that's still there and looks much closer to how it originally did?

That's kind of always been a point of confusion for me with these "how it was meant to be" discussions. Many "purists" will happily tell someone that their preferences are wrong, and not how Doom should be, but most of them also have a list of things that they use that are most definitely not how things were in 1993. Somehow, those things are OK and mine are not though.

[bimshwel]

I DO have fondness for the vintage method of fading the colors into darkness, and once in a while I think about my now largely irrelevant efforts to optimize the base palette, but I also miss some of the socks I used to have. I prefer being able to use 3d sectors.