Rigid body sim on mobile with Box3D

[u/nathan82]

CPU only, 900 objects.

[u/risbia]

How does it decide which way the light is coming from? Great fidget toy

[u/nathan82 → u/risbia]

Just based on rotation sensor data.It picks a starting point above and to the right when you launch, and then moves it relative to device motion.

[u/Srirachachacha → u/nathan82]

Wonder if actual lighting data could be captured from the camera so it perfectly matches the user's surroundings.

This is so cool OP

[u/nathan82 → u/Srirachachacha]

Thanks! ❤️ Yeah I considered that actually, you could even use the camera data to build a cubemap for realtime "accurate" reflections. But ultimately nobody wants their wallpaper app using the camera. What I do have instead is the light sensor reading, so you can brighten/dim the "external" light in the scene depending on if lights are on in the room. That works pretty well.

[u/Srirachachacha → u/nathan82]

>nobody wants their wallpaper app using the camera

So true lol, good point.

[u/Had78 → u/Srirachachacha]

Maybe geodata + time to determine the sun position on the sky, the same for the moon but with a blue tint

[u/nathan82 → u/Had78]

Yes you could use lat+lon data to get "true" sun position data and feed that in. Cool idea actually! I've avoided any kind of identifying information in the app, skipped making it weather reactive too because it's supposed to work fully offline. Wonder if this is worth making an exception for though.

[u/Jwn5k]

I really really like this but holy battery drain hahaha

[u/nathan82 → u/Jwn5k]

Yep that's a concern for sure! Any scene without simulation absolutely sips battery though and you're never on your homescreen for long, so it's viable in general. Just not this particular design.

[u/lumpyferret → u/nathan82]

you could probably customize it and just have a few things floating around.

Maby sell "packs" of various things if you wanted to run a paid app.

Ie sports team logo you could mock up a 3d logo of a sports team and just have one of them rolling around as someones homescreen.

Could make a killing $$$

[u/nathan82 → u/lumpyferret]

Maby sell "packs" of various things if you wanted to run a paid app.

Yep thats the idea, three or four free designs then the rest in content packs for $3 each. Something like that.

Could make a killing $$$

Hopefully, I've been working on this stupid thing for 5 years now! We need a live wallpaper engine that doesn't suck.

[u/BlackSeep1010]

Do you have an apk for this?

[u/nathan82 → u/BlackSeep1010]

This is part of my wallpaper app but the simulation stuff isn't done yet. DM me if you want the app link but it'll be a few weeks at least until I can get this design into the open beta version.

[u/Batteredburrito → u/nathan82]

hows battery drain on this mf

[u/nathan82 → u/Batteredburrito]

Scenes without simulation use less than 1% of total usage in a typical day. Not tested with sim scenes yet, just got it working yesterday. But I don't expect it would be too bad - you're only on the homepage a few minutes total in a day and everything is aggressively stopped when your wallpaper isn't visible.

[u/Firefly360r → u/nathan82]

!remindme 5 weeks

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[u/GreatRedditorThracc → u/Firefly360r]

Remindme! 5 weeks

[u/P13666]

This is really cool! There's also a small part of me that wishes the app icons moved around as well lol

[u/risbia → u/P13666]

Have a threshold if you shake it hard enough, they come loose and roll around

[u/nathan82 → u/risbia]

That's not a bad solution actually! I didn't want to have them move because you need them for, like, launching your apps. 😂

[u/SpicyRice99 → u/nathan82]

Nahnah then you gotta dig through the pile to find your app 😂

[u/risbia → u/nathan82]

Double tap the side of the phone and they snap back into place 

[u/nathan82 → u/risbia]

I mean, the bigger issue is it's compatible with third party launchers and I have no control over the tap zones of the icons. I'll try and get them jiggling though at the very least. 😄

[u/risbia → u/nathan82]

I mean tap the side of the phone itself so the gyro detects the "hits". Since you're using gyro anyway for angles, set a threshold of the gyro receiving a rapid short change in position twice in succession 

[u/Free-Heals-Here]

Man back in the earlier 2000s I jailbroke my iPod touch and there was a tweak someone made that let you do this with your app icons, that was so cool back then.

[u/TheRealVulle → u/Free-Heals-Here]

Yeah, I too had a physics app like this on my iPod Touch in 2007. Fun way to play with the accelerometer 

[u/NickNightrader]

So so cool

[u/Extension_Swordfish1]

Cool as fuck!

[u/FoxlyKei]

I need an APK 😭

[u/ScubaFred]

That's awesome.

[u/AverageOverthinker42]

I love this!!

It would be so cool if you could also make the icons physical objects, while still allowing you to interact with them.

:)