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Motion blur makes sense for films. I have no idea why anyone wants it in a game. The limitations of display technology and of the human eye introduce all the bl

by causi 3y ago

Motion blur makes sense for films. I have no idea why anyone wants it in a game. The limitations of display technology and of the human eye introduce all the blur I could ever want.

JKCalhoun 3y ago
I added motion blur in a slot-machine like game I wrote. http://www.softdorothy.com/Blog/Entries/2011/10/26_Making_The_Devils_Dice_1.html http://www.softdorothy.com/Blog/Entries/2011/10/26_Making_Th...
- jabroni_salad 3y ago
  You only have it on a moving element so that's okay. What gamers really dont like is when you move the camera slightly and the entire scene turns into a deep fried oil painting.
virtualritz 3y ago
> Motion blur makes sense for films. I have no idea why anyone wants it in a game. TLDR; motion blur always makes sense atm. Not less so for games. For games the difference it makes depends on the FPS and the distance an object moves within the FOV. Estimates say humans can see max. 60FPS. Even if your game runs at 120FPS and something moves accross the entire FOV -- that is two discrete samples of that object at most. You will get strobing. Only if you render the geometry with motion blur will this look natural. The alternative is probably to have mutliple 10k FPS but that is wasteful. If your biological limit is around 60FPS, it should be cheaper to generate motion-blurred frames at this rate (where more samples are used in areas with more motion blur) than rendering every pixel of a frame at muliple 10k FPS.
- causi 3y ago
  Human eyes do not work based on discrete frames at all. The entire "sampling" paradigm is completely wrong. Estimates say humans can see max. 60FPS. This is a ridiculous statement. You know that's wrong if you've ever switched your phone between 60 and 120hz. Even without personal experience, most HN readers would be aware that, for example, when the Oculus Rift folks were developing their headset they found 90hz to be the minimum to avoid visual disturbances and nausea in an immersive environment.
  - virtualritz 3y ago
    Ofc the human visual system does not work at discrete frames. However, there is a threshold on how much information your brain can process and tests indicate this maxes out at the temporal detail you can fit into 60 'discrete' frames per sec. For many people it is actually much less. That is: in general. Specifically this threshold is differs based on certain variables; the most important one being available light (number of photons per unit of time). I.e. the less light, the more motion blur there is because there is more temporal integration happening in your brain's visual system. Estimates say your brain goes down to a temporal information density of less than 10 FPS in very low light circumstances [1]. Your brain does perceive motion blurred frames differently. How do I know? I worked in VFX on many blockbuster movies. We do preview stuff using realtime graphics (aka what game engines do) w/o motion blur at equal frame rates as the final frames (which are with motion blur, ofc). Even on projects where we used 60 fps there is visible strobing w/o motion blur. And as I said: even when you preview stuff at 120 fps or more there is visible strobing with geometry that covers big distances in your FOV. Motion from game engines w/o motion blur does not least look like game engines because of this. There is also a night and day difference between post-process motion blur, based on 'smearing' the image based on a motion vector pass and true 3D motion blur. "The Hobbit" triology was done at 60FPS. But it still had motion blur, for obvious reasons. [1] https://www.sciencedirect.com/science/article/pii/S0042698907002118 https://www.sciencedirect.com/science/article/pii/S004269890... EDIT: typos/grammar
    - causi 3y ago
      The Hobbit was recorded at 48fps, not 60. And as I said: even when you preview stuff at 120 fps or more there is visible strobing with geometry that covers big distances in your FOV. Exactly. The game has no idea what is and isn't moving in my FoV because it doesn't know what I'm looking at, only what the camera is looking at. Subjectively, in my experience, games do a terrible job at predicting what I'm looking at and I'd prefer they stop messing up my experience by trying. Strobing is better than smeary mess.
      - virtualritz 3y ago
- kroltan 3y ago
  For (the vast majority of) games the player can be looking at anything on screen, not just a specific point. In real life, eyes track objects in order to minimise blur. But realtime motion-blur implementations just blur everything that moves relative to the camera, which is not correct, and makes the human looking at the screen lose track of the objects they were looking at. If we had pervasive perfect low latency eye tracking then a game could pull off something that actually looks plausible, but that is not the case, so the only games that can get away with it are the ones that are largely a movie and can take advantage of the motion blur cinematographically.
ranger207 3y ago
Yes, motion blur gets turned off immediately on every game that I have. I consider games that don't allow you to turn it off overproduced and likely to have other directorial choices I won't agree with. I would like to see the game environment, not a smeared mess of random colors

by causi 3y ago

Motion blur makes sense for films. I have no idea why anyone wants it in a game. The limitations of display technology and of the human eye introduce all the blur I could ever want.

JKCalhoun 3y ago

I added motion blur in a slot-machine like game I wrote. http://www.softdorothy.com/Blog/Entries/2011/10/26_Making_The_Devils_Dice_1.html http://www.softdorothy.com/Blog/Entries/2011/10/26_Making_Th...

jabroni_salad 3y ago
You only have it on a moving element so that's okay. What gamers really dont like is when you move the camera slightly and the entire scene turns into a deep fried oil painting.

virtualritz 3y ago

> Motion blur makes sense for films. I have no idea why anyone wants it in a game. TLDR; motion blur always makes sense atm. Not less so for games. For games the difference it makes depends on the FPS and the distance an object moves within the FOV. Estimates say humans can see max. 60FPS. Even if your game runs at 120FPS and something moves accross the entire FOV -- that is two discrete samples of that object at most. You will get strobing. Only if you render the geometry with motion blur will this look natural. The alternative is probably to have mutliple 10k FPS but that is wasteful. If your biological limit is around 60FPS, it should be cheaper to generate motion-blurred frames at this rate (where more samples are used in areas with more motion blur) than rendering every pixel of a frame at muliple 10k FPS.

causi 3y ago
Human eyes do not work based on discrete frames at all. The entire "sampling" paradigm is completely wrong. Estimates say humans can see max. 60FPS. This is a ridiculous statement. You know that's wrong if you've ever switched your phone between 60 and 120hz. Even without personal experience, most HN readers would be aware that, for example, when the Oculus Rift folks were developing their headset they found 90hz to be the minimum to avoid visual disturbances and nausea in an immersive environment.
- virtualritz 3y ago
  Ofc the human visual system does not work at discrete frames. However, there is a threshold on how much information your brain can process and tests indicate this maxes out at the temporal detail you can fit into 60 'discrete' frames per sec. For many people it is actually much less. That is: in general. Specifically this threshold is differs based on certain variables; the most important one being available light (number of photons per unit of time). I.e. the less light, the more motion blur there is because there is more temporal integration happening in your brain's visual system. Estimates say your brain goes down to a temporal information density of less than 10 FPS in very low light circumstances [1]. Your brain does perceive motion blurred frames differently. How do I know? I worked in VFX on many blockbuster movies. We do preview stuff using realtime graphics (aka what game engines do) w/o motion blur at equal frame rates as the final frames (which are with motion blur, ofc). Even on projects where we used 60 fps there is visible strobing w/o motion blur. And as I said: even when you preview stuff at 120 fps or more there is visible strobing with geometry that covers big distances in your FOV. Motion from game engines w/o motion blur does not least look like game engines because of this. There is also a night and day difference between post-process motion blur, based on 'smearing' the image based on a motion vector pass and true 3D motion blur. "The Hobbit" triology was done at 60FPS. But it still had motion blur, for obvious reasons. [1] https://www.sciencedirect.com/science/article/pii/S0042698907002118 https://www.sciencedirect.com/science/article/pii/S004269890... EDIT: typos/grammar
  - causi 3y ago
    The Hobbit was recorded at 48fps, not 60. And as I said: even when you preview stuff at 120 fps or more there is visible strobing with geometry that covers big distances in your FOV. Exactly. The game has no idea what is and isn't moving in my FoV because it doesn't know what I'm looking at, only what the camera is looking at. Subjectively, in my experience, games do a terrible job at predicting what I'm looking at and I'd prefer they stop messing up my experience by trying. Strobing is better than smeary mess.
    - virtualritz 3y ago
kroltan 3y ago
For (the vast majority of) games the player can be looking at anything on screen, not just a specific point. In real life, eyes track objects in order to minimise blur. But realtime motion-blur implementations just blur everything that moves relative to the camera, which is not correct, and makes the human looking at the screen lose track of the objects they were looking at. If we had pervasive perfect low latency eye tracking then a game could pull off something that actually looks plausible, but that is not the case, so the only games that can get away with it are the ones that are largely a movie and can take advantage of the motion blur cinematographically.

ranger207 3y ago

Yes, motion blur gets turned off immediately on every game that I have. I consider games that don't allow you to turn it off overproduced and likely to have other directorial choices I won't agree with. I would like to see the game environment, not a smeared mess of random colors