Why so blurry?

[Condoz]

I guess the scaling of the old low resolution graphics is always an issue, but I'd rather have bigger (4x or so) Pixels than a washed out look. I'll look into a solution, but if anyone already has one (Dev's!?) i'd be happy...

[TechDweeb]

Agreed.

[kawacatoose]

I don't have this game but if this game uses Dosbox there should be configuration file in the directory of the game where you can set the settings for the graphics including different ways to render graphics. Fiddling with these settings often gives better result then standard settings.

edit:

Personaly I run dosbox in a window instead of full screen. Old dos games mostly are in a resolution of 320x200, so a screen window 1280x800 is ideal which exaclty 4x the vertical and horizontal pixels. After that you can try different renders and choose which one looks the best.

[Szoreny Klepko]

like kawacatoose said, look into how to configure dosbox's config files. It comes with a bunch of 'smoothing' filters and methods which can be turned off. I'm like you OP in that i prefer crisp big pixels on my old emulated titles.

This is what my ROA from GoG's package is configured to look like:

http://imgur.com/T29adnN

[tiger.uppercut]

i understand that in times of TFTs you dont want it blurry, but come to think of it, thats propably just how it looked on our large blurry CRT screens back then.

especially since the TFTs got high resolutions these days. that it can lead to "real" blurryness instead of pixel artifacts when you scale.

[Anamon]

I hear you, it's a problem when playing games from the CRT era on flatscreens. I personally also prefer sharper pixels to heavy blurring. (I also think that maybe developers would have preferred to get such a sharp picture back in the CRT days, if it had been possible?) A bit of filtering would be okay, but I feel most default settings have it set much too high.

In the DOSBox configuration file, what you should look out for are the options fullresolution, output and pixelshader. Set fullresolution to desktop, any other setting doesn't make sense on flatscreens because the monitor can never do a higher-quality scaling than you can get in software.

As for the output drivers, some of them will filter/blur the scaled output, others won't. If I remember correctly, ddraw and opengl are blurred, while direct3d and openglnb aren't, so try switching to one of the latter two. There can be different behaviour depending on your video drivers and settings.

direct3d is theoretically the most flexible one because you can choose the pixelshader to apply. bilinear.fx comes with DOSBox and does the filtering. You'd have to edit the pixelshader file to change the level of filtering though.

As a side remark, note that unfiltered output has its own set of problems. For example, if your flatscreen's native vertical resolution is not a multiple of the game's original vertical resolution, then not all pixel lines will be the same height. This can look very weird for objects (like a mouse cursor) moving across the screen, because it will seem to "wobble". We will always have to rely on workarounds and compromises when going from CRT to flatpanels...

[tiger.uppercut]

well it all depends. on the C64's the screens were so bad that the graphics were designed to look fine just on these monitors, hinting towards hidden detail that wasnt there. when you plug that into an emulator, it often looks bad. id like to have an emulator that gives me the option to have the real original look, and not just a filter that looks remotely like it. i had to prepare a C64 the other day for an exhibition and i gotta say the graphics have something special to them, which i couldnt find in emulators.

for PCs come to think of it, it was propably a bit sharper than like when the dosbox goes scaling about. it was just this thin smoothness between the pixels. it wasnt blurry, the pixels were well visible, but they were glued together a bit. thats why we were so surprised by TFT screens when they came out. that you can see the space between the pixels, and that the pixels had such sharp edges.

in the end you never know what they designed for, you simply gotta play around with the dosbox scaling filters until it feels right, and then stop thinking about it before all you see is pixels ^^.

i think ill be trying to edit or program one of these shaders next time i try a game, thanks for the hint. let me know if you have a lead towards how to go about that.

the wobblyness is a good argument, but i think with fullHD it should be unnotable when displaying 320x200 resolutions? or is it a 640? its all so long ago.

[Anamon]

Exactly, artists made the graphics work best with the displays of the day, including all their limitations. Which is why sometimes, the unfiltered blocky look can make it very hard to see what some things are, as they were supposed to be displayed with some degree of blurring. But yes, I think the default blurring that most software does is way too strong, let alone that the "blurring" resulting in CRTs is very different from a bilinear blur.

There is actually quite a number of people writing shaders for CRT-like looks and there have been hundreds. I don't have a particular favourite I could recommend, it's also very much a matter of taste. Some of them go really deep into emulating physical properties of CRTs: scanlines, screen curvature, pixel brightness rising much faster than it falls again, shadow masks, etc... Check out this article[filthypants.blogspot.ch] for some cool examples.

Last time I noticed wobbliness was with Gabriel Knight at 320x200 on a 1920x1080 display (note 1080 not divisible by 200) and it really bothered me when a character, or even just the mouse pointer, moved up or down. A very slight blur helped a lot. I don't remember exactly how I did the configuration, but I managed to reduce the default bilinear blur by having DOSBox internally render the game to a higher resolution (640x400 or even 1280x800) before applying the filter.
1080p displays are generally a lot worse at this than 1200p ones, because 1080p is a stupid resolution. You can uniformly scale a lot of common resolutions of old games to 1200p: 320x200, 320x240, 640x400, 800x600 all work fine, while 1080p can do none of those.

[tiger.uppercut]

it wouldnt help to reduce the resolution of the screen without scaling would it? then it would be the divisable, but the aspect ratio would still be wrong right? as old resolutions were 1,6 and new ones were 1,33 both filling up a 4:3 space.

[Anamon]

The problem is that a flatscreen can't really "scale". On CRTs you would just make the spacing between the lines different, but flatpanels have a fixed native resolution of discrete pixels which can't change. If you lower the display resolution, the screen will just (try to) solve the same problem in hardware. You would end up with the same wobbling problem.

That's why I mentioned above you should never set DOSBox to anything other than "fullresolution=desktop" on a flatscreen (assuming your desktop resolution is the native screen resolution, of course). That way, DOSBox can use all the pixels of the screen separately, and you can play around with software scaling and filtering settings to try and find something that you think looks good.

[tiger.uppercut]

yeah i meant turning off screen scaling and setting a divisible resolution.

but wouldnt fix the aspect ratio tho, so yeah, pretty pointless.

[Anamon]

Oh, I see. You mean setting to a lower resolution and displaying it not stretched to full-screen, but letterboxed in the middle? Actually, I don't think this would give you any aspect ratio problems. You will just have borders to the side as well as at the top and bottom of the screen.

So if the black frame doesn't bother you it's actually a pretty good solution. Set the resolution to anything lower than your native one (like 1280x800 instead of 320x200 on a 1080p display), let DOSBox scale it up uniformly and set your monitor to letterboxing. No more wobbling.

[tiger.uppercut]

yeahbut if the screens back then were 4:3 when they had 320x200, and they still had 4:3 when they had 320x240, 640x480 etc then the pixels themselves must have had a different size.

and that would mean that if you use the new, regular size, then the image would be flattend a bit, right?

uhm now what resolution is this game in again ^^

[Anamon]

Ah yes, the pixel aspect ratio, I completely forgot. DOSBox can take care of that (aspect=true I believe), but that would probably introduce filtering again. Theoretically, because you only need to scale vertically to correct the aspect ratio, you would just need to choose a target resolution that is divisible by both. But then such a resolution is harder to find again.

Argh, what a mess I think the best option is the one I mentioned above: have DOSBox render to an (aspect-corrected) very high resolution, and then downscale it for display on the flatscreen. Render it small and it will be blurrier, render it bigger and the blur will be less strong, so you can decide which you think looks best. It uses up some more performance, but should work fine.

Reals of Arkania is 640x480 I believe, which is already 4:3. So you could for example do a 1280x960 letterboxing without problem.

[tiger.uppercut]

i got one more: would supersmpling, i.e. running the screen at a higher resoltion than it actually has and then downsampling help anything? it would be at least a kind of filter, but i dont think it can reduce wobblyness.

[Anamon]

Originally posted by tiger.uppercut (-A.S-)^^^:

i got one more: would supersmpling, i.e. running the screen at a higher resoltion than it actually has and then downsampling help anything? it would be at least a kind of filter, but i dont think it can reduce wobblyness.

Yes, that's what I meant above ;) sorry, I sometimes have trouble expressing these things clearly. This is what I did after the wobbling annoyed me in Gabriel Knight. You have to find a compromise between blurriness and wobbliness, but I found that the wobbling stops being noticeable even with very little blur.

I don't exactly recall the DOSBox settings I used, but you can achieve it with scalers. Internally, DOSBox always renders the game to its original resolution. Then, you can force it to upscale the picture (uniformly, so no wobbling being introduced) and correct the aspect ratio. Then it will automatically be downsampled to whatever resolution fits the DOSBox window (i.e. the native screen resolution when in full-screen mode). The higher the upscaling, the less blur you have.

I might give this another try and post the settings I ended up using.