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Show HN: Boing

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Re: Show HN: Boing

#131

Post by [deleted] »

InsomniacL wrote: post #78
junon wrote: post #6

Love this. Had to cheat, naturally. setInterval(()=>{const canvas=document.getElementById('canvas');const startX=266;const startY=198;const rect=canvas.getBoundingClientRect();const startClientX=rect.left+startX;const startClientY=rect.top+startY;let endClientX,endClientY,distance;do{endClientX=Math.random()*window.innerWidth;endClientY=Math.random()*window.innerHeight;const dx=endClientX-startClientX;const dy=endCli…

Waiting for somebody to write the code to recreate the Star Wars Imperial March: https://www.youtube.com/watch?v=-NDLlWtudpE

[deleted]

Re: Show HN: Boing

#132

Post by gregsadetsky »

HelloUsername wrote: post #129
gregsadetsky wrote: post #102

Earlier quoted context omitted.

Just downloaded Firefox on iOS and tested it and sound works here - can you check this other site please: https://learningsynths.ableton.com/ ? There will also be no sound there if your phone is in Silence mode. However if Learning Synths works but not mine, then something else is happening. Thanks!

"Your browser does not support this site. Please try using a recent version of Chrome, Firefox, Safari, Edge, or Opera." Probably because I have Lockdown mode enabled, and/or NextDNS

I'm not showing that message (ie those words are not from me) so yeah sorry - I'm not sure what's going on

Re: Show HN: Boing

#133

Post by SAI_Peregrinus »

coffeecoders wrote: post #38

Funny thing: this feels "realistic" because it’s not perfect physics. A perfectly simulated Hooke's law spring actually looks fake and too stiff. But if you let the animation wobble a bit more and slow down the damping, our brain reads it as weight and squishiness. It’s basically controlled sloppiness.

Hooke's law only accounts for the force the spring applies, not the mass of the spring itself. Once you have to account for the mass of the spring, how that mass distribution changes as the string stretches & compresses, and how that alters the momentum it quickly loses its simplicity. That's far too difficult to do by hand, but it's what the real world does so I'd rather say that Hooke's law is a first-order approximation of spring force, not a perfect law for describing linear spring behavior.

Re: Show HN: Boing

#135

Post by Bewelge »

InsomniacL wrote: post #78
junon wrote: post #6

Love this. Had to cheat, naturally. setInterval(()=>{const canvas=document.getElementById('canvas');const startX=266;const startY=198;const rect=canvas.getBoundingClientRect();const startClientX=rect.left+startX;const startClientY=rect.top+startY;let endClientX,endClientY,distance;do{endClientX=Math.random()*window.innerWidth;endClientY=Math.random()*window.innerHeight;const dx=endClientX-startClientX;const dy=endCli…

Waiting for somebody to write the code to recreate the Star Wars Imperial March: https://www.youtube.com/watch?v=-NDLlWtudpE

Only the first few notes

(function () { function rateToDistance(rate) { const minR = 0.09; const maxR = 4.65; if (rate maxR) rate = maxR; const t = (rate - minR) / (maxR - minR); return 400 * t; } function dispatchMouseEvent(type, target, clientX, clientY) { const event = new MouseEvent(type, { view: window, bubbles: true, cancelable: true, clientX, clientY, screenX: clientX + window.screenX, screenY: clientY + window.screenY, buttons: type === "mouseup" ? 0 : 1, button: 0, }); target.dispatchEvent(event); } const canvas = document.getElementById("canvas"); function triggerPull(distance) { const rect = canvas.getBoundingClientRect(); const startX = 266; const startY = 198; const startClientX = rect.left + startX; const startClientY = rect.top + startY; const endClientX = startClientX + distance; const endClientY = startClientY; return new Promise(resolve => { dispatchMouseEvent("mousedown", canvas, startClientX, startClientY); setTimeout(() => { dispatchMouseEvent("mousemove", canvas, endClientX, endClientY); setTimeout(() => { dispatchMouseEvent("mouseup", canvas, endClientX, endClientY); resolve(); }, 50); }, 50); }); } const semitones = 12; const notes = { G: Math.pow(4, -9 / semitones), A: Math.pow(4, -7 / semitones), B: Math.pow(4, -5 / semitones), C2: Math.pow(4, -4 / semitones), D2: Math.pow(4, -2 / semitones), E2: Math.pow(4, -0 / semitones), F2: Math.pow(4, 2 / semitones), G2: Math.pow(4, 4 / semitones), }; async function playWithPitch(rate) { const r = rateToDistance(rate); await triggerPull(r); } async function playScale() { const qrt = 200; const hlf = 400; const fll = 800; const pause = 15; const playNote = async (note, dur) => { await playWithPitch(note); await new Promise(res => setTimeout(res, dur)); }; const loop = async () => { await playNote(notes.E2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.E2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.E2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.C2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.G2, qrt); await playNote(notes.E2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.C2, fll); await new Promise(res => setTimeout(res, pause)); await playNote(notes.G2, qrt); await playNote(notes.E2, fll); await new Promise(res => setTimeout(res, pause)); await new Promise(res => setTimeout(res, pause)); await new Promise(res => setTimeout(res, pause)); }; await loop(); await loop(); await loop(); } playScale(); })();

Re: Show HN: Boing

#136

Post by pierrec »

gregsadetsky wrote: post #49
aetherspawn wrote: post #32

The sound is not physics based, the boing sound keeps going if you grab the head, likewise sometimes the sound ends before the vibration finishes.

Well spotted! I'd love a synthesized version - if anyone has pointers.

Having done a fair amount of audio physical modeling, I'll just say a synthesized version that's both fast and realistic would be possible but difficult. The difficulty is at least "it would make an impressive presentation at DAFx [1]", though I might be underestimating it, and it's more "you could make it your master's thesis at CCRMA [2]"

Ideal springs are a common, simple element in this field, but this kind of spring is very much not that.

You're probably better off improving the sample-based version by fading out the audio when necessary and using different samples based on the way it's triggered. If you have "ultra-dry" samples (maybe taken with a contact mic), you can add a convolution effect with a well-chosen impulse response, this will allow you to sharply cut off or adjust the audio and still have a natural-sounding tail.

[1] https://www.dafx.de/

[2] https://ccrma.stanford.edu/

Re: Show HN: Boing

#137

Post by ianberdin »

junon wrote: post #6

Love this. Had to cheat, naturally. setInterval(()=>{const canvas=document.getElementById('canvas');const startX=266;const startY=198;const rect=canvas.getBoundingClientRect();const startClientX=rect.left+startX;const startClientY=rect.top+startY;let endClientX,endClientY,distance;do{endClientX=Math.random()*window.innerWidth;endClientY=Math.random()*window.innerHeight;const dx=endClientX-startClientX;const dy=endCli…

https://boing.playcode.io

Re: Show HN: Boing

#138

Post by gregsadetsky »

pierrec wrote: post #136
gregsadetsky wrote: post #49

Earlier quoted context omitted.

Well spotted! I'd love a synthesized version - if anyone has pointers.

Having done a fair amount of audio physical modeling, I'll just say a synthesized version that's both fast and realistic would be possible but difficult. The difficulty is at least "it would make an impressive presentation at DAFx [1]", though I might be underestimating it, and it's more "you could make it your master's thesis at CCRMA [2]" Ideal springs are a common, simple element in this field, but this kind of sp…

I'm extremely grateful for this. My most deeply held secret is that I wish I could do this for a living - digitally modeling weird/beautiful objects/instruments and work on that forever haha. (And maybe make pedals out of them, I don't know)

If you don't mind humoring me (I'm quite the novice in this field), if I automated the recording of "all" possible positions for a spring (say I had a motor positioned in a way that would let me pull the spring in any polar direction), would that make modeling potentially easier?

There might be a "train an AI, here's 1000 recordings" angle, but I'm not necessarily interested in/asking about that.

Just strictly for modeling, would it help the R&D phase to have a lot of high sample rate recordings? Thanks a lot!

P.S. Also, if you have a good intro to DSP class/book, I'd love to hear it. I know about a few, but a recc is always appreciated

Re: Show HN: Boing

#139

Post by junon »

ivanjermakov wrote: post #93
junon wrote: post #6

Love this. Had to cheat, naturally. setInterval(()=>{const canvas=document.getElementById('canvas');const startX=266;const startY=198;const rect=canvas.getBoundingClientRect();const startClientX=rect.left+startX;const startClientY=rect.top+startY;let endClientX,endClientY,distance;do{endClientX=Math.random()*window.innerWidth;endClientY=Math.random()*window.innerHeight;const dx=endClientX-startClientX;const dy=endCli…

while true; do curl -X POST -Ss https://respected-accordion-31461.ondis.co/boing &; sleep 0.1; done

When I wrote this there wasn't a leaderboard, and that wasn't the point of the cheat anyway. Was only later I noticed the network requests starting to hit after boinging.

Re: Show HN: Boing

#140

Post by pierrec »

gregsadetsky wrote: post #138
pierrec wrote: post #136

Earlier quoted context omitted.

Having done a fair amount of audio physical modeling, I'll just say a synthesized version that's both fast and realistic would be possible but difficult. The difficulty is at least "it would make an impressive presentation at DAFx [1]", though I might be underestimating it, and it's more "you could make it your master's thesis at CCRMA [2]" Ideal springs are a common, simple element in this field, but this kind of sp…

I'm extremely grateful for this. My most deeply held secret is that I wish I could do this for a living - digitally modeling weird/beautiful objects/instruments and work on that forever haha. (And maybe make pedals out of them, I don't know) If you don't mind humoring me (I'm quite the novice in this field), if I automated the recording of "all" possible positions for a spring (say I had a motor positioned in a way t…

That's funny, I was trying to do other stuff after posting my comment, but my brain kept working in the background, against my will, looking for the best approach to actually model this. Honestly, I was probably being pessimistic about the difficulty of a synthesized version, but I still think your current approach (don't synthesize, use samples) is more reasonable and can be made more responsive.

I don't think that recording a large number of starting positions would help that much with creating a (non-ML) model, and I doubt a high sample rate would provide much useful information either. A more common approach would be to try getting separate sounds for the impulse and the resonant body, though they may be impossible to really separate, and the actual model may end up more complex than that.

You probably have a good starting point already with your code for the animated model. I think the sound mostly comes from the collision between coils (collisions not visible in your animated model), and almost entirely from the lowest couple of windings that are against the wall. This is your impulse. The resonant body might be in 2 parts: the wall and the long end of the spring. Your existing model can tell you when to trigger the impulses, and how much force to put into them.

For resources, one of my favorite intros to DSP is the one by Sean Luke: https://cs.gmu.edu/~sean/book/synthesis/

I wrote my own intro to physical modeling, though it focuses on different instruments: https://www.osar.fr/notes/waveguides/

Julius O. Smith has an encyclopedic amount of content on the topic, though it's often condensed into math that can be hard to apply: https://ccrma.stanford.edu/~jos/

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