I'm not super familiar with this area so I don't follow... Why is animation any more difficult? I would think you could attach the basic 3D shapes to a skeleton the same way you would with polygons.
There are lots of reasons you don’t see a lot of SDF skeletal rigging & animation in games. It’s harder because the distance evaluations get much more expensive when you attach a hierarchy of warps and transforms, and there are typically a lot of distance evaluations when doing ray-marching. This project reduces the cost by using a voxel cache, but animated stuff thwarts the caching, so you have to limit the amount of animation. Another reason it’s more difficult to rig & animate SDFs is because you only get a limited set of shapes that have analytic distance functions, or you have primitives and blending and warping that break Lipschitz conditions in your distance field, which is a fancy way of saying it’s easy to break the SDF and there are only limited and expensive ways to fix it. SDFs are much better at representing procedural content than the kind of mesh modeling involved in character animation and rendering.
One possibility, a little backwards maybe, is to produce a discrete SDF from e.g. a mesh, by inserting it in an octree. The caching becomes the SDF itself, basically. This would let rendering be done via the SDF, but other logic could use the mesh (or other spatial data structure).
Or could the engine treat animated objects as traditional meshed objects (both rendering and interactions)? The author says all physics is done with meshes, so such objects could still interact with the game world seemingly easily. I imagine this would be limited to characters and such. I think they would look terrible using interpolation on a fixed grid anyways as a rotation would move the geometry around slightly, making these objects appear "blurry" in motion.
Sampling an implicit function on a grid shifts you to the world of voxel processing, which has its own strengths and weaknesses. Further processing is lossy (like with raster image processing), storage requirements go up, recovering sharp edges is harder...
But isn't this what the author is doing already? That's what I got from the video. SDF is sampled on a sparse grid (only cells that cross the level set 0) and then values are sampled by interpolating on the grid rather than full reevaluation.
I get it. But what I'm saying is that the impact of a single misguided administration, while can be very devastating, is not enough to write off american super power status in research.
With appropriate planning and funding, the next administration can definitely reverse the trend.
> The information to properly land the plane is in the manual. The required air speed and altitude have never been a secret, if you read the manual (which I guess most kids didn't).
It's also on-screen. What's missing is the acceptable ranges -- +/- 100 for altitude, +/- 50 for speed, per the post. Knowing that the slop for altitude is much higher is definitely helpful information.
> The trick is just to know the numbers to aim for and ignore the instructions.
Interestingly, the instructions are actually all correct. If it says, "Left! Left!" for instance you will crash if you don't fix it.
I think the disconnect might be that altitude and speed somewhat feedback on each other and it takes time for your inputs to settle, so it always feels like you're chasing the instructions.
I think people focused too much on the speed too early on, which put them in a stall condition without any feedback they were stalling. For most of the run, you want to be losing altitude so you don't notice, but near the end you're probably too low with not enough speed to climb, so even though you're pulling up, you're still losing altitude, and that's where people got the idea that their inputs didn't "matter."
Speaking of the soundtrack, before Virt (Jake Kaufman) made it big (composer behind Shantae, Shovel Knight, Ducktales Remastered, a few others), he made this: https://www.youtube.com/watch?v=5uEUImofSms
"Bogey at your 6", the combat theme from the game, but remixed as if Konami had made it for the VRC6, the NES mapper chip that added 3 additional oscillators that made the Japanese release of Castlevania III what it was; he made this using Scream Tracker (or possibly a newer tracker, but its saved in S3M format), because tracker-like chip emulators didn't exist yet (Furnace, et al).
The Japanese release of the game flips around the "soundless" sections with the music section, suggesting that listening to that rocking track for most of your flight is the intended experience.
I knew there was a version out there that flipped the music around... but I don't remember the "painted line" aircraft carrier... I wonder if someone made a rom hack like 20 years ago that kept the graphics but flipped the music...
I never got that far in the game... but that song gave me a visceral body memory of "difficult things in games that trigger intense 8 bit music" memories.
I wonder how this went down. "Hey LG, this is the Microsofts. Just had an idea how we could give your entire customer base the middle finger, wanna hear it?"
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