Almost instant motion sickness due to distorted rendering

Please check

• if you have activated motion blur in the grahics card settings software, if so, please disable it

• if you have disabled VSYNC in Minecraft graphics settings, if so, please enable it

I've been testing this issue on 1.13, and it still exist, the same as in the original.

It is NOT related to any graphics card setting. Please look at the video in the original bug report.

Original bug report has video

https://youtu.be/yraaPpr3qGo

FOV=70 (default)

As my reported bug (MC-135666) was linked to this and I was asked to explain the difference, I recorded a similar situation to your original video; can you ( @Paul ) point out if your issue is apparent in my video?

Youtube upload (compression could be an issue): https://www.youtube.com/watch?v=MWoed9BvLsM

Raw (lossless) download: https://drive.google.com/file/d/1TnXlTutaNQw6I7XVOtYrifOZrbXOWgOy/view?usp=sharing

I am experiencing the motion sickness and headaches as well due to the sides of the screen being distorted. I did NOT have these issues prior to the update, but I haven't been able to play the game in years because of it. I can't even watch let's plays. Can confirm that changing FOV, Vsync, head bobbing, etc. does nothing to help.

@Shawn : I find it difficult to recognize what's exactly happening in your video, but logically, if I'm looking at Minecraft rendering and it has 2 different issues that happen all the time, both issues should be visible simultaneously.

If I understand correctly, your issue is about blurring of pixels, while my issue is about shape and movement of pixels such that straight lines get strangely curved.

@Paul : is this still ongoing? I'm not coming back to minecraft until someone confirms this has been resolved - it's not worth risking the hours of illness for me or my wife to try again.

My entire household is more or less stuck playing older versions of Minecraft (around version 1.6-1.7; we're still experimenting to try to narrow down exactly which version change started giving us problems). I also can't even watch lets plays and changing FOV/framerate/using windowed mode doesn't seem to help me either, though I'm currently experimenting with trying 4:3 resolutions instead of 16:9 to see if that reduces the nausea inducing effect. I'll update if I can figure out which version started causing problems for us.

EDIT: I feel very silly. In our case it had nothing to do with the rendering; it turns out playing the game at above 30 fps was triggering simulation sickness in all of us. Locking the frame rate to max 30 fps solves it.

I tried installing a java server and client (can't remember if it was 1.6), but it didn't seem to make a difference for us.

We binged on minecraft in January of 2018 for many hours, and stopped playing around March 2018. When we came back to the game a few months ago... boom - motion sickness within 30 minutes. My wife gets it almost instantly if she tries to play again, but I can tolerate maybe 20 minutes. The nausea doesn't wear off for hours, though

 EDIT: I tried setting MAX Frames Per Second to 30 in the options.txt file inside the MCPE folder. It made no difference for our motion sickness. I'm not 100% sure it actually did limit the FPS.

@Meredith Swann - is that how you set Max FPS to 30?

@Jeff - no, I lowered it directly from the in-game options menu through Video Settings, but I was playing the Java Edition. I've never played Pocket Edition/Bedrock, so I don't know if the same option is available... A quick google search got me at least one add-on/mod that lets you cap framerate, so if there isn't a built in option there's something to try. Fingers crossed for you guys.

I can confirm that this occurs in both Java 1.14.3 and Bedrock edition. I looked for and confirmed the distortion in both versions on the same PC, running Windows 10.

On Java Edition: I set the FOV to default and looked at a block, then moved the block to one corner of the screen. As it moved, the block got considerably larger closer to the edge of the screen, and appeared to change shape from a cube to sort of diamond shaped.

On Bedrock Edition: I turned off the "FOV can be altered by gameplay" setting, which locks FOV to default, ignoring the FOV setting. I did the same test, moving a block from the center of my screen to the edge. The results were mostly the same as Java, but the distortion seems more severe in Bedrock.

This gets worse in both version the wider the FOV setting is, and is horribly nauseating at anything greater than 90 degrees. On Java edition, I can play at 90 degrees after getting used to it. On Bedrock, trying to do that makes me want to vomit. I would consider myself more resistant to motion sickness than the average person, particularly motion sickness induced by movement on a screen. My family members get sick almost immediately if they watch me play.

EDIT: Out of curiosity, I set my FOV to 30 (the minimum) on Java Edition and repeated the test. The distortion is slight, but still present. Therefore I conclude that the cause of this distortion has nothing to do with the FOV setting. It's something inherent in the way the camera works. I really hope you can fix this. I can put up with it, but it's annoying at best.

There seems to be a lot of confusion about what this distortion is and whether it is expected or unique to Minecraft. The stretching at the sides of the screen is an expected result of linear perspective which is used by virtually all hardware accelerated graphics engines. The way this works is that the 3D scene within the field of view is projected onto a flat rectangle, this flat rectangle is then displayed on your screen. In ideal viewing conditions there will be no apparent distortion since the rays from the viewer to the display and from the projected scene to the scene will be parallel. There are few important things to note:

• The apparent size of an object is not necessarily the same as its physical size on screen (i.e. width in pixels) due to perspective. In other words, the pixels towards the edge of the screen appear relatively smaller than pixels in the center of the screen, so objects need to be physically larger (in pixels) to appear to be consistently sized on screen.

• The amount of stretching depends on the field of view. The larger the field of view, or equivalently, the closer you are to your display, the more stretching needs to occur at the edges to keep the physical size and apparent size consistent across the entire screen.

• If the field of view used by the rendering engine does not match your field of view to the display then you will see distortion since the physical size and apparent size will not be consistent across the entire screen. People can typically tolerate some slight discrepancies without an issue, but if you look for the distortion it will become hard to ignore as others have pointed out above.

If you are seeing stretching at the edges of your screen in normal viewing conditions then you should decrease the field-of-view in game and/or move closer to the screen. If you are seeing pinching at the edges of your screen in normal viewing conditions then you should increase the field-of-view and/or move further from the screen.

The video linked in the description is using 70 degree vertical field of view and a 48:9 aspect ratio which gives a horizontal field of view of 150 degrees. If you're watching this video fullscreen on a 24-inch 16:9 monitor then the optimal viewing distance is 5.6 inches from the screen. (Typical viewing distances are 20-40 inches). You can see the same distortion in Quake 4 in this video, or Skyrim in this video.

Motion sickness can be caused by a lot of things, including misaligned field of view. However, the distortion at the edges of the screen described in this issue is not a defect, it is required for perspective-correct rendering.

High framerate causes motion sicknes for me too, i have 240hz monitor lmao, I keep framerate caped for minecraft to 60. Anyways i dont think this is serious isusue here, because minecraft uses extraordinary 180fov and that distorts everythink like swazenager.

Past minecraft versions were played with stable low framerate, and curent minecraft versions fluctuate too much with that (devs think that improving max fps times will remove 0fps lagspikes turns out far from reality /s). And this is where minecraft came to isusue. There is a setting to cap framerate at 60, manny users just disable that so just add "higher framerates can cause montion sicknes with high fow" when howering ower fps with mouse cursor.

@Carter

It's not FOV, but let's ASSUME for a brief moment it is. I play Minecraft, I get instant motion sickness, I play Skyrim, I can play for hours without problems. Which FOV should I use for Minecraft such that I get the same painless experience as for Skyrim?

Let me assure you that I've tried ALL FOV settings, and non-linear distortion still persists. Compare that to Skyrim where no issues are visible at all at the default settings.

The somewhat comparable experience would be to the renderers in older software rendered games such as the original Tomb Raider. For speed reasons, shortcuts were taken, that lead to similar extreme nausea-inducing non-linear distortions. WIth the advent of hardware rendering, I've had no such experience anymore ever since (except when looking at someone else playing a fast 3D shooter running around in corridors).

@Carter I have to chime in here and agree with Paul. I've also tried ALL FOV settings, from 30 to 120, and the motion sickness persists. Moving closer or further from the computer monitor has also been tested, with no apparent influence on susceptibility to motion sickness (at least for us).

Since you seem to be implying that FOV distortion due to linear perspective rendering is commonly misunderstood, and Minecraft's method of rendering is common and similar to other games, let me try to be more clear so people like you understand what the bug reporters are actually talking about. Hopefully, more people acknowledge that there is a problem that is UNIQUE to Minecraft and can attempt to help, rather than pointing out a fallacious misunderstanding that attempts to dismiss the original complaints/reports as general "user error" or something similar.

The biggest difference between Minecraft and Quake or Skyrim is that Minecraft lacks the ability to zoom in or out (move the camera closer or further from the character) which changes (for most games) how the FOV linear perspective rendering translates pixel size towards the edges of the screen in a non-square ratio.

Myself and my wife can play Minecraft for much longer without feeling sick if we stay in 3rd person mode (although this greatly hampers general play-ability as you have an avatar blocking your view and don't have a crosshair.) Switching to the default 1st person mode greatly exaggerates the linear perspective "stretching" which in turn greatly amplifies the negative effects that induce motion sickness. 

Something about how this pixel-stretching occurs in Minecraft is unlike any other 1st-person game I've played (and I've played many, including every single one of the games mentioned in all of the bug reports concerning simulation/motion sickness). It has become worse in terms of the nausea-inducing phenomenon over the past months/years. A combination of very linear blocks with all their various linear stretching back and forth from square to rectangular exaggerations with high FPS and other video/rendering techniques is causing a disconnect in the brain for some people. Though we don't fully understand it yet, some game producers have responded to player feedback with simple solutions like returning to a previous iteration of a graphics rendering technique in order to satisfy player needs. Others have tried introducing options to players involving camera movement and placement.

So far, Mojang has introduced zero new options for the camera/rendering besides a static FOV adjustment slider. Maybe one more camera/perspective/render option added to the game would be the fix for most people who currently get sick.?

@Paul, @Jeff, I didn't mean to suggest that you could prevent motion sickness just by adjusting field-of-view or viewing distance, or that there aren't problems that are unique to Minecraft that cause motion sickness; only that the distortion itself is not a bug and is not unique to Minecraft. @Paul I can't answer your question of what field-of-view to use for Minecraft to get the same experience you get in Skyrim because there are a lot of things that can cause motion sickness.

I'm not sure why you don't believe that Skyrim has the same behavior. I've taken a couple of screenshots from a Skyrim video showing the same effect. (Note that the title of the video is "Skyrim Realistic Sun mod" but the screenshots were taken from the "Standard sun" section of the video). You can see that the moon is no longer circular when it's rendered on the edge of the screen due to linear perspective. I've outlined it with an ellipsoid but the actual shape is more egg-shaped since the amount of stretching increases across the shape.

Along the lines of what @Jeff was saying, it could just be that the blocky art style makes the effect more pronounced in Minecraft compared to other games like Quake or Skyrim.

@Carter, I agree you can set FOV in Skyrim that it will distort rendering. I do not use that, only the default setting. It works fine, and I don't experience any motion sickness, nor do I notice any distortion. In Minecraft on the other hand, I've tried many, many, many FOV settings, and I cannot get the distortion to disappear.

In Minecraft the rendering seems to stretch shapes into irregular forms, much more than I've seen in other games. That includes the strange distortion of the (square) sun near the edges of the screen.

It may very well be the blocky art style is primarily responsible for making the motion sickness so pronounced, whereas Skyrim's (and most other games) complex 3D triangulated surfaces and textures do a great job of tricking our brain and hiding the distortion from us.

Regardless, very old FPS games like Wolfenstein that had a blocky style due to the corridor style level design still don't manage to get me sick, even today. I'm not sure what the exact differences are, but old Minecraft didn't do this to me a year ago. 

Has anyone done a comparison of the vertical - horizontal stretching ratio in Minecraft vs other first person games? How the diagonal stretching of blocks and block surfaces translates to a parallelogram vs a non-symmetrical trapezoid, and how that compares to how other games do it?

@Jeff Brunet That's because Wolfenstein is built entirely different compared to minecraft. Believe it or not, it isn't actually a fully fledged 3D. Here is some more information if you are interested https://www.youtube.com/watch?v=zb6Eo1D6VW8. The issue with Minecraft is well described in the previous comments.

But to make it short and compact, these things add up to the feeling of motion sickness: parallax, textures, viewing distance, and that damned stretching. For me changing the textures back to the old ones helped. And this leads me to believe that it's the fault of new textures and the main reason would be how detailed they have become.

For me it's clearly the non-linear/non-perspective-correct stretching that's the culprit.

Since the most recent updates I have been unable to play, as the current changes NOW make me nauseous, and I am a paying customer of a realm by the way.   Prior to the recent changes I was able to play daily for hours upon hours with no problems.   Furthermore,  the visuals now seem to be like having tunnel vision no matter how much I try to adjust the settings.    Seeing this BUG marked as a normal priority by Mojang is extremely disappointing, as I have no doubt others too are now experiencing this same issue but just haven't figured out where or how to complain about it.  These people are probably just trying to be patient as I have been doing, while praying that Mojang will address this bug.  

I also get motion sickness only from playing minecraft (and not from other games, including older ones from the nineties like doom/quake, nor from modern FPS's). However, it seems to me from memory, that this has always been the case, while @Paul says that he remembers not feeling nauseous when playing the older versions of minecraft.

Could someone confirm if this issue really appeared from a certain version onward, or if it has always been present in the game? I will start experimenting myself, but maybe someone already has the answer. On the other hand @Lisa Doe reports getting the symptoms only from the most recent updates...

An easily accessible example of good handling of the screen edges is Google Street view. Look for example at this view: https://www.google.com/maps/@59.3310028,18.0575814,3a,90y,30.86h,110.3t/data=!3m6!1e1!3m4!1snX3Nczx7nzUjEskHiMVdTw!2e0!7i16384!8i8192
Even though the camera is zoomed out as far as Google Maps allows it and the building is pretty close, right angles are almost preserved, things farther away or farther to the edge of the screen still look normal and the usual requirements like straight lines staying straight are also preserved. I don't know what Math they use exactly, but it could be used as a reference.

I just attached two screenshots of the same pyramid that visualise this issue very well. It should not be squished as much.
Someone please tell me if I'm confusing related issues here.

The pyramids are a good example I think. It shows the angles at which the sides are rendered are not correct. Rendering is always a trade-of, however in Minecraft it's especially bad such that many people literally get sick of it.

Just curious, have any of you tried with the FOV set to exactly 60 degrees? Most games use 60 as it's the best sweet-spot between warped and telescoped rendering, I verified in minecraft and 60 has almost no angle distortion, while not looking like your head is attached to a plank being swung around that is 50deg and lower.

An extra game-dev rule is limiting directional movements with cameras, in that they should only be moving in mostly one direction or rotation at a time. If the camera for example were to fly outwards from the target, while also strafing to one side, that can cause spontaneous nausea in some people. In the case of minecraft, I would suggest an option to be added to snap motion to fixed rates, as opposed to having constant momentum, especially for creative mode. The user can then simply refrain from using WASD and the mouse at the exact same time, and not have to worry about the character still sliding around when they're looking around.

One other thing to note is looking down can be a sure-fire way of triggering nausea in a lot of people, especially if you're way up high and slam the view straight down. The effect can also be witnessed in real life when looking down from a high-rise for example, in a sense it could be confused with acrophobia, but they're not the same.

That all seems like workarounds, but other games and 3D renderings manage to do it without them, so they should hopefully not be needed.

60 degrees is a really narrow FOV; the default FOV for Quake and Half life 1 is 90 degrees and I can play those for hours on end. And they are much more about fast and sudden movements which should trigger nausea even more compared to minecraft (so there is something specific to minecraft that causes it). For playing Overwatch (a more modern fps) I use FOV 103 with no issues.

There's clearly some issue with the rendering here; it's just that since it affects a minority of players, it never gets attention. Like the bug [MC-973] - Bat noises are painful and cause headaches - Most people didn't care about bat sounds, but for some of them it was game-breaking. The bat noise is much easier to fix than 3D rendering, of course.

think this could be because Minecraft is missing a barrel distortion setting:

https://www.decarpentier.nl/lens-distortion

If we could have access to this through settings, or it could be auto set along with FOV to reduce warping, I think we'd all be throwing up a lot less. This bug actively prevents me from showing or recommending minecraft to friends because it affects me so badly.

Can confirm in 1.17.1. Just do small circles with the mouse and focus on the very edge of the screen, and the effect will be eerily similar to that of the Nausea effect in-game.

@Josiah Walker 

The barrel distortion article is actually pretty nice, and does explain some of the effect. When comparing with the actual effect (see https://www.youtube.com/watch?v=yraaPpr3qGo), you would expect ALL shapes to be barrel distorted, which is NOT happening. I suspect the renderer uses a non-uniform way to render objects, which subtly changes the "normal" perspective distortions present in (mostly) all other (modern) video games (which are not causing any problems for me).