|
every year or so i am reminded that that i don't know how or why light, magnetism, or anything fundamental works, and i just go into a existential spiral for a bit until i get hungry
|
#
?
Aug 28, 2020 05:27
|
|
|
|
| # ? May 13, 2024 21:41 |
|
|
FutonForensic posted:every year or so i am reminded that that i don't know how or why light, magnetism, or anything fundamental works, and i just go into a existential spiral for a bit until i get hungry Good news, no one else actually knows for certain anyway and I'm pretty sure they do the exact same thing you do. Sometimes I catch myself contemplating infinity. I'm okay with it, but I often wonder how I manage to fit the idea in my head.
|
|
#
?
Aug 28, 2020 05:37
|
|
|
Dareon posted:I often wonder how I manage to fit the idea in my head.
|
|
#
?
Aug 28, 2020 05:38
|
|
|
Cardiovorax posted:It's probably one of the smaller infinities. Yeah, that's probably i-- Waaait a minute.
|
|
#
?
Aug 28, 2020 05:47
|
|
|
RandomFerret posted:If you wanted to accurately simulate the way light works down to the individual photons using a physics engine, you'd need to model it that it works as a particle, but then hack it to work like a waveform to make different colours and frequencies. It's wild that the little sensor on a garage door that keeps it from closing if something is in the way only works because light is both a wave and a particle.
|
|
#
?
Aug 28, 2020 05:55
|
|
|
In one of the Digital Foundry Minecraft RTX videos they made a pinhole camera thing which worked just because the game had raytracing. I thought that was pretty impressive. Would link but I’m on mobile.
|
|
#
?
Aug 28, 2020 06:14
|
|
|
Dareon posted:Yeah, that's probably i--
|
|
#
?
Aug 28, 2020 06:15
|
|
|
Fauci's fuckup regarding the masks is kind of understandable, it was an attempt to square a circle of too few masks for medical professionals, with a paternalistic attitude that the general public would not know how to use masks properly. But let's face it the people who want to be worthless consumerist pieces of poo poo demanding service at Cheesecake Factory would seize upon any excuse to gorge themselves on treats at the expense of service staff, and they're going to look for any excuse to sabotage anti-pandemic policy. Edit: PYF favorite glitch in the plagueworld
|
|
#
?
Aug 28, 2020 06:28
|
|
|
rodbeard posted:It's wild that the little sensor on a garage door that keeps it from closing if something is in the way only works because light is both a wave and a particle. Please elaborate
|
|
#
?
Aug 28, 2020 22:53
|
|
|
RandomFerret posted:If you wanted to accurately simulate the way light works down to the individual photons using a physics engine, you'd need to model it that it works as a particle, but then hack it to work like a waveform to make different colours and frequencies.
|
|
#
?
Aug 28, 2020 23:09
|
|
|
Cardiovorax posted:What kind of unit were you using for velocity that the physics simulation could hit the maximum value for a signed 64-bit integer without already having reached the speed of light and refusing to accelerate any further anyway? The issue isn't hitting the maximum value for a float64, it's that floats don't provide continuous coverage of the number line, and that coverage gets spottier and spottier the further you get from 0. So if you have a large value X that can be represented with float64s, and you add a small acceleration Y to it, you get a speed of X back, because (X+Y) is closer to X than it is to the next representable float64 value. For reference, (c in meters per second) / (maximum value represented by a float64) is about 1e-300, so I recommend using units of "planck units per lifetimes of the universe".
|
|
#
?
Aug 28, 2020 23:14
|
|
|
TooMuchAbstraction posted:The issue isn't hitting the maximum value for a float64, it's that floats don't provide continuous coverage of the number line, and that coverage gets spottier and spottier the further you get from 0. So if you have a large value X that can be represented with float64s, and you add a small acceleration Y to it, you get a speed of X back, because (X+Y) is closer to X than it is to the next representable float64 value. And for a visual representation of this, here's a clip of Mario falling for so long that all the Y-axis values relating to the camera's movement, Mario's movement, and basically all the 3D graphics get way hosed up. He becomes blocky in a vertical way specifically because his vertices are "snapping" to those little skips between values. As stated, closer to the zero point of a float there's a lot more actual possible values between, say, 1.0 and 2.0, but out at like 100000.0 where Mario is, most of the precision is lost. Because of this, the Y position of his vertices also lose massive amounts of precision. The same thing would happen in a slightly different, more horizontally glitchy way if this dude were to use hacks to fly Mario in a straight line for a very long time. https://www.youtube.com/watch?v=2s6_pAXK7hE computers are neat
|
|
#
?
Aug 29, 2020 00:24
|
|
|
Shai-Hulud posted:Please elaborate light goes through the gap between the garage door and the garage roof, hits the super position of the car which is both in the driveway and not in it. depending how tight the garage door is, its gonna open or close
|
|
#
?
Aug 29, 2020 00:39
|
|
|
dreamin of semen posted:And for a visual representation of this, here's a clip of Mario falling for so long that all the Y-axis values relating to the camera's movement, Mario's movement, and basically all the 3D graphics get way hosed up. He becomes blocky in a vertical way specifically because his vertices are "snapping" to those little skips between values. As stated, closer to the zero point of a float there's a lot more actual possible values between, say, 1.0 and 2.0, but out at like 100000.0 where Mario is, most of the precision is lost. Because of this, the Y position of his vertices also lose massive amounts of precision. The same thing would happen in a slightly different, more horizontally glitchy way if this dude were to use hacks to fly Mario in a straight line for a very long time.  God I love glitches like this, I always forget why they happen. Some of the later environmental stuff in this one is legitimately unsettling, as is Mario devolving into a small pile of anguished pixels.
|
|
#
?
Aug 29, 2020 00:43
|
|
|
I think an extremely simplified version of it would be that you had to save coordinates, but can use only three significant digits. So near the origin you can be really precise with x = 0.0341 and y = 1.48 But if you travel far away, you can't have numbers like x = 54329.43 and have to use x = 54300 instead. And if you have lots of points that are close to each other, they'll get the same coordinates.
|
|
#
?
Aug 29, 2020 01:24
|
|
|
^^ yep, pretty much, if you want to kinda play around with how floats actually work in memory, have a go at float toyCaptain Hygiene posted:
Aesthetically it's definitely one of my faves I just spent a little bit messing around with forcing this to happen in my own engine and man, if it wasn't effectively a seizure waiting to be caused, I'd love to implement this as some sort of graphical effect. Just force everything in the world to render at +1.11726E+07 on every axis and let the hellscape begin type stuff dreamin of semen has a new favorite as of 01:38 on Aug 29, 2020 |
|
#
?
Aug 29, 2020 01:33
|
|
|
The thing that really annoys me is that the actually noteworthy thing is the real time path tracing, which is the part where they simulate the trajectories of the photons themselves. Ray tracing is just the comparatively ancient technology of shooting rays out of the camera to find what objects are visible (and you can use simpler methods than path tracing to work out the lighting), and that's been something that can be done in real time for ages.
|
|
#
?
Aug 29, 2020 02:07
|
|
|
Not to be a pedant but what you just described as raytracing is raycasting, and what you described as path tracing is raytracing. Raytracing is simulating photons firing out of lights and bouncing around, illuminating where they hit. It's slow and old and mostly for rendering that isn't realtime. Raycasting is the ancient stuff, Doom's graphics use raycasting, firing rays from the camera to find solids. Raymarching is VERY cool but only truly useful for graphics written using algorithms. Path tracing is a sort of combination of raycasting and raytracing, using rays fired from the camera to test where they hit and find lighting averages in a very neat way. It's pretty efficient, works great without much code, and it straight up naturally simulates a lot of effects that would normally take extremely complicated shaders, without any actual effort put into writing code to do so. Here's a video that I love a lot https://www.youtube.com/watch?v=frLwRLS_ZR0 A lot of people do use raytracing as a blanket term though, and I can see why NVidia went with it, it's recognizable if you like computers enough to be buying a GPU over a grand
|
|
#
?
Aug 29, 2020 02:47
|
|
|
Shai-Hulud posted:Please elaborate Now I'm struggling to find a source that breaks down a fun fact I learned almost 20 years ago in a way I can still understand because it's been so long since I've needed to understand physics. Basically there's a polarized filter on the sensor so the light needs to be a wave to actually reach the sensor, but light needs to be a particle to carry the electrical charge that completes the circuit when it hits the sensor.
|
|
#
?
Aug 29, 2020 03:01
|
|
|
I fall back to my standard explanation that complex technology is actually powered by ghosts
|
|
#
?
Aug 29, 2020 03:02
|
|
|
I've always loved this https://www.youtube.com/watch?v=Y_Fz0C8nb70
|
|
#
?
Aug 29, 2020 03:19
|
|
|
OK I'm bad at stuff so this has taken a few rewrites. Oops!dreamin of semen posted:Not to be a pedant but what you just described as raytracing is raycasting, and what you described as path tracing is raytracing. As Wikipedia says, ray casting is "a non-recursive ray tracing rendering algorithm that only casts primary rays." The terminology of these things is a little bit wibbly, so even if you don't cast additional rays when you encounter a partially transparent object, it can still be called ray tracing. It stops being just ray casting at that point, however. So, yes, I described ray casting (because ray tracing always includes ray casting), but I also described ray tracing, especially since I included the possibility that you can use additional, more advanced techniques to calculate the lighting. Traditionally, with ray tracing, you do some numerical magic using a vector pointed directly to the light source from the spot you found. Path tracing comes in a few flavours, but they involve shooting rays from the light sources, casting rays from the simulated photodetector and only counting ones that would correspond to a photon, or a combination of the two. It would obviously not be very performant to do ONLY the "shooting rays" step and not combine it with either regular ray tracing or the modified ray tracing variation that wikipedia describes as "gathering rays," so nobody does that. So, yes, path tracing is generally implemented with some form of ray tracing in it. Either way, what sets it apart is the individually simulated photons aspect. To contribute, one thing I like is when you get to see things out of bounds, and occasionally in Burnout 3, you can end up slipping out of where you're supposed to be when you crash really hard, and see some actually impressive work, considering it's stuff you can barely see when you're zooming by on the intended track! I'm always kind of sad I can't stick around to explore it before I get shunted back onto the course. It would be cool if someone could hack a free camera for that game... Toastline has a new favorite as of 05:41 on Aug 29, 2020 |
|
#
?
Aug 29, 2020 04:48
|
|
|
rodbeard posted:Now I'm struggling to find a source that breaks down a fun fact I learned almost 20 years ago in a way I can still understand because it's been so long since I've needed to understand physics. Basically there's a polarized filter on the sensor so the light needs to be a wave to actually reach the sensor, but light needs to be a particle to carry the electrical charge that completes the circuit when it hits the sensor. The light is then absorbed by the sensor like a particle and excites its electrons into a higher state of energy, which means the material is now temporarily an electrical conductor until it re-emits the energy as a new photon.
|
|
#
?
Aug 29, 2020 05:25
|
|
|
Captain Hygiene posted:I fall back to my standard explanation that complex technology is actually powered by ghosts  Pretty much.
|
|
#
?
Aug 29, 2020 05:31
|
|
|
That's all fair enough. In hindsight that was very semantic of me and kinda general and weird, as well as being not my wheelhouse and mostly osmosed definitions from learning about regular realtime 3D. Probably should have just not, my apologies. Also, big agree. It's a drat shame that PCSX2 doesn't have a built-in camera unlock. I'm clearing out my Death Stranding recordings and found this, it's probably the weirdest unintended thing I've seen (apart from the trikes) in 70+ hours, which is a little bit impressive https://i.imgur.com/1TGxTMu.mp4
|
|
#
?
Aug 29, 2020 06:48
|
|
|
was reminded today about Fallout 4 any% speedruns, which are so glitch-heavy they almost take longer to explain than to do. and hey look, the best runner-explaoner of that category just released a brand new full-commentary video of it https://www.youtube.com/watch?v=-VFgizBWjFI
|
|
#
?
Aug 29, 2020 06:51
|
|
|
dreamin of semen posted:That's all fair enough. In hindsight that was very semantic of me and kinda general and weird, as well as being not my wheelhouse and mostly osmosed definitions from learning about regular realtime 3D. Probably should have just not, my apologies. I see you are also using the Correct Hood.
|
|
#
?
Aug 29, 2020 07:22
|
|
|
Cardiovorax posted:A polarized filter will only accept a specific range of angles that depends on the physical positioning of the filter - put two filters of the same type on top of each other at right angles and they will become completely opaque. and the part that REALLY bakes my noodle is that the directionality is probabilistic, which means that you can make it not opaque again by adding another filter in between those two https://www.youtube.com/watch?v=zcqZHYo7ONs
|
|
#
?
Aug 29, 2020 08:36
|
|
|
since y'all are explaining the technicalities of stuff like this, can someone break down why the Super Scope only works on CRTs? I heard a pretty nonspecific mumbling about refresh rates and color values or something but also I'm dumb as hell and could be absolutely misremembering
|
|
#
?
Aug 29, 2020 14:39
|
|
|
Korremar posted:since y'all are explaining the technicalities of stuff like this, can someone break down why the Super Scope only works on CRTs? I heard a pretty nonspecific mumbling about refresh rates and color values or something but also I'm dumb as hell and could be absolutely misremembering The Super Scope requires a display that uses a scanning electron gun, which is how CRTs work. The electron gun fires electrons at phosphors in the screen, causing them to emit light; they then continue to glow for a bit before decaying and going dark. It does this by scanning horizontally across the screen, one row at a time, very quickly. By continually refreshing the phosphors (pixels), you get a display that's stable to human eyes but kind of flickery if you have a decent sensor. The sensor on the scope is able to detect the momentary increase in brightness that represents the electron gun scanning across the part of the screen that the scope is pointed at. When the player pulls the trigger and the sensor sees the electron gun, the scope sends a signal to the game saying "I saw the electron gun", and the game is able to look at which row of pixels it was painting, and specifically where in that row it was painting, to figure out what the gun was pointing at. This is waaaay more pleasant to use than the NES lightgun, which required visibly flickering the screen so the gun could report what colors it sees. But it's also a bit fiddly and relies on fairly precise timing, so you generally need to calibrate it for it to work properly.
|
|
#
?
Aug 29, 2020 14:59
|
|
|
The really short version is that the timing of the display is different. CRTs have almost instantaneous input (press button and thing happens on screen) while newer TVs are sliiiiightly slower. Unless you're playing fighting games or music games the difference is usually imperceptible to your average person but an electronic device is going to be very particular.
|
|
#
?
Aug 29, 2020 16:02
|
|
|
Doc Hawkins posted:was reminded today about Fallout 4 any% speedruns, which are so glitch-heavy they almost take longer to explain than to do. This guys vids are great, also his name makes me laugh every time. He has to change it to "tomatoangus" during AGDQ because of course.
|
|
#
?
Aug 29, 2020 16:18
|
|
|
Korremar posted:since y'all are explaining the technicalities of stuff like this, can someone break down why the Super Scope only works on CRTs? I heard a pretty nonspecific mumbling about refresh rates and color values or something but also I'm dumb as hell and could be absolutely misremembering Retro Game Mechanics Explained has a very technical video on how all the SNES controllers worked, with a section dedicated to the Super Scope and exactly how it detects where it's pointed at the screen and why it only works on CRTs: https://www.youtube.com/watch?v=2Dw7NFm1ZfY&t=1086s.
|
|
#
?
Aug 30, 2020 04:53
|
|
|
I have no idea why this happens but it's great. https://twitter.com/SilverSoul164/status/1299877627960979459
|
|
#
?
Aug 30, 2020 04:57
|
|
|
Howling @ the Nanako one
|
|
#
?
Aug 31, 2020 06:05
|
|
|
That would be a great thread title
|
|
#
?
Aug 31, 2020 06:30
|
|
|
Pretty good posted:Howling @ the Nanako one Go home Nodoko you're drunk
|
|
#
?
Aug 31, 2020 09:48
|
|
|
TooMuchAbstraction posted:I have no idea why this happens but it's great. Looks like it's working ngrmadly to me.
|
|
#
?
Aug 31, 2020 10:29
|
|
|
Pretty good posted:Howling @ the Nodoko one ♫ ~ Every doy's greot ot your Judes! ~ ♫ Barry Bluejeans has a new favorite as of 14:11 on Aug 31, 2020 |
|
#
?
Aug 31, 2020 13:58
|
|
|
|
| # ? May 13, 2024 21:41 |
|
|
Pretty good posted:Howling @ the Nanako one
|
|
#
?
Aug 31, 2020 14:54
|
|