Post B0PyvisSOL8fIILsJM by flaki@flaki.social
(DIR) More posts by flaki@flaki.social
(DIR) Post #B0DtLa0P4IotgaUo1g by ancientjames@mastodon.social
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Latest voxels!Flickery when filmed ✓Distracting reflections ✓You kind of have to be there ✓
(DIR) Post #B0E0GJCsnVldohlbLU by aeva@mastodon.gamedev.place
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@ancientjames amazing! how does it work?
(DIR) Post #B0E0rsOQwFrFey5DCC by ancientjames@mastodon.social
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@aeva It’s projection mapping - the block has ~38000 points laser etched in it, arranged so they’re uniformly separated in 3D space, but all neatly laid out in a 2D grid when viewed from the projection point. You can see some stray points where I haven’t got the calibration nailed.
(DIR) Post #B0E1wR14FiMI9btKFM by aeva@mastodon.gamedev.place
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@ancientjames oh wow that's brilliant :O!
(DIR) Post #B0E4zpuMSfTm5O4HdA by yngmar@social.tchncs.de
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@ancientjames @aeva How is that block even made. Laminated sheets of glass?
(DIR) Post #B0E6QDWlMqisp7AofA by h5e@tech.lgbt
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@aeva @ancientjames yes very clever 😄 how are you projecting onto them?
(DIR) Post #B0E6QEIyTbHtEdjJoG by ancientjames@mastodon.social
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@h5e @aeva using a mems laser projector
(DIR) Post #B0E9Johl2ojvxixKE4 by ancientjames@mastodon.social
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@yngmar @aeva No, it's a single block of glass. The laser is focused inside the block - like this https://www.youtube.com/watch?v=sOrby692Uag
(DIR) Post #B0EAPmXW6iQuwGZeJU by h5e@tech.lgbt
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@ancientjames @aeva are you using only part of the projection? Or is it very far away with a very narrow beam?
(DIR) Post #B0EAPnElVv1n6OoBiy by ancientjames@mastodon.social
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@h5e @aeva The projector is only about 140 mm away from the block. The addressable volume is a truncated pyramid, but I've arranged the point cloud in a cuboid within that. Each ray from the projector can only address one point, and by ensuring that the more diverging rays tend to address closer points, and the more parallel rays tend to address distant points, it's possible to massage the whole thing to create a uniform distribution within the block.
(DIR) Post #B0EAa07CUM5twF8aJc by ancientjames@mastodon.social
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@h5e @aeva There are some triangular slivers on each side that didn't fit, and the little hexagons you see at the bottom right and left are there to catch those rays. I think they'll be good for 2D status stuff - minimap, score, that sort of thing.
(DIR) Post #B0EBjlHIbigqlv4yES by ancientjames@mastodon.social
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I learned my lesson from the previous displays, and this time wrote the simulator before writing the actual driver code.It allowed me to quickly catch a flipped axis which I can believe would have otherwise taken me days to figure out.
(DIR) Post #B0EBmHl8oVFm5eF0PA by gsuberland@chaos.social
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@ancientjames feesh
(DIR) Post #B0EC3HnNvrJh7pOgEa by yngmar@social.tchncs.de
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@ancientjames @aeva Ohh, I see. Thanks!
(DIR) Post #B0EGb01otcr3gSTpce by secretbatcave@don.secretbatcave.co.uk
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@ancientjames ooo are you using super fast optics to adjust depth?
(DIR) Post #B0ENUnEIGhKpvlInse by PatHightree@mastodon.gamedev.place
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@ancientjames @aeva So, kind of like a pointilist Lumarca. How the heck do you calibrate 38000 points ?!?!?
(DIR) Post #B0FRbt8xGyyxH3P6ae by ancientjames@mastodon.social
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@secretbatcave I'm using a mems scanning laser projector which doesn't need focusing, and it's lighting up a point cloud where each possible ray from the projector can only hit a single point on the way through.
(DIR) Post #B0FmcKjWnC4HscZ292 by ancientjames@mastodon.social
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I rendered off an animation showing how the points are aligned when seen from exactly the right spot.
(DIR) Post #B0Fnayh3LoDNBmK9J2 by ancientjames@mastodon.social
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Incidentally, the viewport version of that animation doesn't work - the points only line up when refraction is taken into account.I've used the equation for refraction countless times in shaders, but somehow it kind of blows my mind that it actually works IRL.
(DIR) Post #B0GWOdYkb1iG6bvjIe by jon_valdes@mastodon.gamedev.place
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@ancientjames @aeva wow, that's an awesome idea. I'm wondering about the 38K point count. I'd have expected a 720p projector to give you 1280x720/4=230400 usable pixels (leaving a ring of dark pixels around each lit one). Is the 38K number because of some limitation on the etching side of things?
(DIR) Post #B0GlVm6MjXnFwEVzH6 by The4thCircle@mastodon.gamedev.place
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@ancientjames That is genius.
(DIR) Post #B0HeQvLcQOD4e4LiDI by ancientjames@mastodon.social
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@jon_valdes The projector does some image space geometry correction to deal with nonlinearity in the scanning, so it's not 1280x720 actual pixels that come out of it. I think I could get down to 4x3 decimation if I got perfect calibration, but it's at 5x4 that you get clearly separated dots, and 6x4 gave me a regular spacing and a bit of room for my own image space correction.
(DIR) Post #B0IeTLvOmEHioHCe1o by jon_valdes@mastodon.gamedev.place
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@ancientjames makes sense! Thanks for the explanation 🙂Wondering... does each dot block most of the light for its pixel? If so, I wonder if you could put another layer of dots in the shadows of the first ones, and then add another projector at a different angle targeting those shadowed dots, to increase resolution Anyway, super cool project!
(DIR) Post #B0JV4U4YdrN4PWVvJQ by secretbatcave@don.secretbatcave.co.uk
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@ancientjames ooooo sweet, even more fancy! Excellent work
(DIR) Post #B0JZj3spJj6IsMdC3k by ancientjames@mastodon.social
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@jon_valdes It just blasts through the dots like they're not there. To make denser targets you'd need more etched points per dot, and this is already down near the resolution limit of the engraver.
(DIR) Post #B0KMMKkvJaPmIZj6zQ by jon_valdes@mastodon.gamedev.place
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@ancientjames damned physics with all its "limitations"!
(DIR) Post #B0Pp4lQ3JMNYF4jpc8 by ancientjames@mastodon.social
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It's fun discovering what sort of content works best on these displays. With the spinning LEDs it was wireframe spaceships. This thing is all about museum quality loot.
(DIR) Post #B0Prgsu28TUOMf4CH2 by ancientjames@mastodon.social
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@twilliability The glass block has thousands of points laser etched inside it. They're small enough that you can't really see them unless there's a light shining on them. There's a projector aimed at the block (through the black panel), and it's carefully aligned so that each pixel in the projected image lights up just one of the points in the block. This means that it's possible to light up any point within the block by just setting the colour of the associated image pixel.
(DIR) Post #B0PtQS2oQW7AL7SsLY by upmultimedia@mastodon.gamedev.place
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@ancientjames amazing
(DIR) Post #B0PvGtwS39LTsH3zbU by ancientjames@mastodon.social
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@twilliability Definitely more like blue noise. There was a lot of processing to get a nice uniform distribution. There's a render here showing the arrangement https://mastodon.social/@ancientjames/115550998233041107
(DIR) Post #B0Pw911PwTnfTEBpdQ by ancientjames@mastodon.social
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@twilliability Don't be sorry for asking! I'm struggling with how to explain it succinctly.
(DIR) Post #B0PyvisSOL8fIILsJM by flaki@flaki.social
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@ancientjames do you have a good article/explainer/link handy for "laser-etching transparent glass cubes at very specific depth for dummies"? Just curious of the physics/technology involved.(but also, cool stuff!!)
(DIR) Post #B0Q1wtBTr9FXPcUv0C by ancientjames@mastodon.social
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@flaki Maker’s Muse did a video about it: https://youtu.be/sOrby692Uag
(DIR) Post #B0QxgoTDPSDFV4pdDs by jon_valdes@mastodon.gamedev.place
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@ancientjames ok, that is 100% in Stargate hologram territory
(DIR) Post #B0SIcpx2FnPz89gXQm by ancientjames@mastodon.social
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The resolution isn't great, but you can still play games on it.
(DIR) Post #B0SQNfN06yMXbS6iCu by fredds@mamot.fr
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@ancientjames if a single guy can create this kind of display as a hobby, how comes we still don't have real (by real I mean "movie theatre") sized display? Is it a physics problem? an economic one? Or, are you a genius, being the first person to create this kind of display using this technics? ;)
(DIR) Post #B0STGPFNxP09Qzm6u8 by ancientjames@mastodon.social
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@fredds I'm not the first person to come up with this approach.3D displays of any sort seem to be a novelty that most people aren't really interested in.Volumetric displays like this have a serious drawback in that they can't simulate occlusion, and the scene has to lie entirely within the device. There might be a future in integral imaging displays (and I'll probably build one at some point), but I have no illusions that there's an industry waiting to be created. I just think they're neat.
(DIR) Post #B0SZudQ3HheMhFKVs0 by aeva@mastodon.gamedev.place
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@ancientjames i want one
(DIR) Post #B0SlR1QAgFHDtq21KK by jarkman@chaos.social
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@ancientjames @h5e @aeva That is a very lovely thing.
(DIR) Post #B0SonfovSPQHQf6RsW by WiteWulf@cyberplace.social
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@ancientjames that looks amazing, and reminds me of the images from the past they create in the TV show DEVS 😍
(DIR) Post #B0T2fGDQAdNZ3gRX7Y by yves@luther.social
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@ancientjames I never would have thought that I could ever see one of my all-time favorite video games with that fidelity. Thanks for sharing and for bringing so much joy to my birthday!
(DIR) Post #B0T48FdhUXBRcj7fkW by jtruk@mastodon.social
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@ancientjames Zarch! (or Virus as we had it on the Atari ST). Lovely aesthetic, and great choice to showcase 😄My memories of that game are mostly trying to wrestle mouse controls and flipping the ship into the ground
(DIR) Post #B0TlWc4K2zJAAMRDAO by ancientjames@mastodon.social
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@jtruk @yves it works really well with just a slightly bigger volume https://youtu.be/ILNbnWneTIg
(DIR) Post #B0UFY0yHwUIkJaCSlk by yves@luther.social
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@ancientjames @jtruk Holy Moly! I really need to dig deeper into this technology. BIG THX!
(DIR) Post #B0UZm1EpkG2MHPtUga by ancientjames@mastodon.social
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This probably won't go in the build video because it gets a bit confusing, but I thought it was a nice way to verify the setup. It's a camera arranged so it can be mounted in place of the projector, with the same form factor and attachment point. If everything is lined up properly, it sees the point cloud as a nice regular grid.
(DIR) Post #B0VGXQeZGZV6mxDivw by PatHightree@mastodon.gamedev.place
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@ancientjames That's ingeneous, I was wondering how you're tackling the calibration
(DIR) Post #B0VeNY1bOzapefodZg by fredds@mamot.fr
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@ancientjames oh, I see. Nonetheless, your work is amazing.
(DIR) Post #B0WYldR4X0BOorn8Bk by ancientjames@mastodon.social
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You're just going to have to trust me that this is really 3D.
(DIR) Post #B0paJhAMxVzGC21SEK by ancientjames@mastodon.social
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Here's the build video for the new volumetric display! Lots of swivelcam footage of it doing its thing.https://youtu.be/wrfBjRp61iY
(DIR) Post #B0qew3NTQ5ud3jeqkS by jon_valdes@mastodon.gamedev.place
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@ancientjamesGorgeous. Absolutely love it
(DIR) Post #B0qnQILp73z7oqojRI by didier@malenfant.net
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@ancientjames bad apple on this or it doesn't count 😜
(DIR) Post #B0qp8wLlrGg4ZPe3Ki by subROV@mstdn.social
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@ancientjames thank you for your general awesomeness. You are truly an inspiration 😀
(DIR) Post #B0t67axVzYFZTRADWC by mathias_becker@mastodon.social
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@ancientjames what are The Limits? Is it imaginable that the pixel count will be increased so that it looks like 4k UHD?
(DIR) Post #B0t67baVeZRTQNPMIa by ancientjames@mastodon.social
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@mathias_becker There's plenty of room to increase the point density without going to crazy extremes - there are higher resolution laser engravers than the one I had access to, and there are higher resolution projectors than this. Aligning it soon becomes the entire challenge, and I'm not sure I'd want to tackle one much finer than this (at least not if I'm doing it just for fun).
(DIR) Post #B0t6KVmuWqhxCVMYhE by ancientjames@mastodon.social
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However if you want something that 'looks like' 4K, volumetric displays really aren't the way to go. Either you're talking about 4000x2000 pixels in a plane, so you need > 1000 planes to keep things isotropic (1000 4K outputs simultaneously); looked at the other way, driving this display with a 4K projector gives you 8 million points to play with, which comes out to an underwhelming 200x200x200 voxel volume.
(DIR) Post #B0t6MwXu0xQMlgVClc by ancientjames@mastodon.social
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It also doesn't handle view dependent effects - you can't render a realistic scene with purely additive points.I think the only type of glasses free 3D display that's likely to get any traction is using integral imaging - basically a lenticular display (like Looking Glass), but extended in both axes.
(DIR) Post #B0wD3r9z63cNiR2ZAe by johninparis@zx81.social
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@ancientjames This is really cool. I've enjoyed following along as you tried these two different types of volumetric displays. (Especially since I hadn't known about those types before you shared your projects!)
(DIR) Post #B0x0yhbmB5aSLrm96u by johninparis@zx81.social
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@ancientjames Back in the early days of the plasma displays in laptops, I often wondered if it'd be possible to make a volumetric display with plasma.The idea being that you could have lasers on two axes, so that the energy level where they crossed would be enough to excite the plasma. (Later I learned that plasma doesn't emit in the visible spectrum. Plus, I'd guess that a container of gas might not allow a stable image anyway.)
(DIR) Post #B0x0yj4AkztasE4L0i by johninparis@zx81.social
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@ancientjames But I remembered the idea of dual-axis lasers when you started sharing this project.Would something like that allow a higher resolution with using this project's engraved glass? And could it work with another sort of medium that wouldn't require to you pre-engrave it?
(DIR) Post #B0x0yjegZF6QhT9UvI by ancientjames@mastodon.social
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@johninparis There are displays (or at least papers about them) using two two lasers to excite a doped glass block - search for 'upconversion volumetric display'. That's a bit out of my league though.
(DIR) Post #B0xPrevyDi1MstxYRM by ancientjames@mastodon.social
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A group at Columbia University built a display using this principle in 2006. The game they ran on it was Pac Man, which was a 25 year old game at the time. GTA 3 is now a 25 year old game, so I thought it would be neat to run that on mine. https://www.youtube.com/watch?v=wrfBjRp61iY&t=461s (asterisk)
(DIR) Post #B0yCswMvmLMn08oKIa by jtruk@mastodon.social
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@ancientjames beautiful (and that makes me feel old 😄).I'm thinking about what might play to the display.How about Jet Set Radio; similar release date. Cel-shading might look crisp?
(DIR) Post #B1SBhzVw1d6Sh7YE3E by johninparis@zx81.social
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@ancientjames Oh, neat! Thanks very much for that info and for providing a search query. My apologies for such a late reply, but I do appreciate your taking the time to point me in that direction.