i nerd sniped myself tonight and i imagine the NSA operative who is assigned to me is very confused by the increasingly erratic and frustrated google searches for HOW DO I CALCULATE THE MOON WHERE IS THE MOON
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@aeva @jon_valdes generally cpu trig is not so bad, but does vary between platforms if you're just calling the c stdlib functions (but we're talking differences of 1 ulp or so). so yes, absolutely you can get a warmer fuller soundstage by switching to a different sin.
@dotstdy @jon_valdes maybe I'll call the expensive exact soft sin oscillator "gold plated sin" 🤔
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@dotstdy @jon_valdes maybe I'll call the expensive exact soft sin oscillator "gold plated sin" 🤔
@aeva @dotstdy @jon_valdes start a new genre "deca-dance"
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@aeva @dotstdy @jon_valdes start a new genre "deca-dance"
@demofox @dotstdy @jon_valdes well so far I can't tell the difference by ear between the soft sin and the double precision sin that clang gives me
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@demofox @dotstdy @jon_valdes well so far I can't tell the difference by ear between the soft sin and the double precision sin that clang gives me
@demofox @dotstdy @jon_valdes assuming I didn't screw anything up adapting Jon's shader toy, the 30 iteration soft sin also has the surprising property of being able to clip out of the expected -1.0 to 1.0 output range https://github.com/Aeva/mollytime/blob/af58e9237903856b6193a116ae6408038dc47d4a/src/patch.cpp#L319
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@demofox @dotstdy @jon_valdes assuming I didn't screw anything up adapting Jon's shader toy, the 30 iteration soft sin also has the surprising property of being able to clip out of the expected -1.0 to 1.0 output range https://github.com/Aeva/mollytime/blob/af58e9237903856b6193a116ae6408038dc47d4a/src/patch.cpp#L319
@aeva @demofox @dotstdy @jon_valdes There's lots of versions of CPU sin/cos as well. The fastest is basically identical to the GPU one - about 12 bits of precision, IIRC. Then they do iteration internally if you want higher precision. There's no magic - everything costs!
As you noticed, sometimes it's better not to call sin-vs-cos, because you're not guaranteed to get magnitude 1.0. In those cases it's better to get sin and derive the other by doing sqrt(1-sin^2).
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@aeva @demofox @dotstdy @jon_valdes There's lots of versions of CPU sin/cos as well. The fastest is basically identical to the GPU one - about 12 bits of precision, IIRC. Then they do iteration internally if you want higher precision. There's no magic - everything costs!
As you noticed, sometimes it's better not to call sin-vs-cos, because you're not guaranteed to get magnitude 1.0. In those cases it's better to get sin and derive the other by doing sqrt(1-sin^2).
@aeva @demofox @dotstdy @jon_valdes Also, if you care about precision at all, do range reduction yourself beforehand. Otherwise you have no idea how it's being done internally.
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@aeva @demofox @dotstdy @jon_valdes Also, if you care about precision at all, do range reduction yourself beforehand. Otherwise you have no idea how it's being done internally.
@TomF @demofox @dotstdy @jon_valdes I already do the range reduction. I learned that the hard way once upon a time XD
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wikipedia: even the ancient babylonians knew how to use math to figure out what the moon is up to
me: great how do i do that
wikipedia: 😏
today's extremely basic astronomy question that i'm finding surprisingly difficult to find an answer to: are geographic coordinates and equatorial coordinates the same coordinate system except one is for looking up and the other is for looking down, or is there some essential conversion step needed to correlate them?
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today's extremely basic astronomy question that i'm finding surprisingly difficult to find an answer to: are geographic coordinates and equatorial coordinates the same coordinate system except one is for looking up and the other is for looking down, or is there some essential conversion step needed to correlate them?
i feel like i'm so close to getting this working. i found a simple implementation of ELP2000-85 that gives the approximate ecliptic coordinates and distance of the moon for a given julian century, i found math for translating between ecliptic and equatorial coordinates, and the math for working with the julian calendar looks easy enough, so i just need to figure out the missing conversions and decide on an internal time keeping standard
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i feel like i'm so close to getting this working. i found a simple implementation of ELP2000-85 that gives the approximate ecliptic coordinates and distance of the moon for a given julian century, i found math for translating between ecliptic and equatorial coordinates, and the math for working with the julian calendar looks easy enough, so i just need to figure out the missing conversions and decide on an internal time keeping standard
i think astronomy would be a lot simpler if ancient peoples didn't get so hung up on conceptualizing celestial bodies as spheres and simply invented linear algebra first
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i think astronomy would be a lot simpler if ancient peoples didn't get so hung up on conceptualizing celestial bodies as spheres and simply invented linear algebra first
@aeva On cosmology sequence breaks: Terence Tao noted that an ancient Greek heliocentrist got his arguments shot down because others said, hey, if the earth moves so much yet the stars seem to stay still, the universe would have to be *thousands* of times bigger than anyone figures it is. And how would you know, back then, it was way *more* than thousands of times bigger?
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i think astronomy would be a lot simpler if ancient peoples didn't get so hung up on conceptualizing celestial bodies as spheres and simply invented linear algebra first
@aeva a lot of things would be simpler if cults based on "perfect" shapes hadn't done all the [gestures] that they did
divine geometry is a helluva drug
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@aeva On cosmology sequence breaks: Terence Tao noted that an ancient Greek heliocentrist got his arguments shot down because others said, hey, if the earth moves so much yet the stars seem to stay still, the universe would have to be *thousands* of times bigger than anyone figures it is. And how would you know, back then, it was way *more* than thousands of times bigger?
@rf they were so close lol
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@aeva a lot of things would be simpler if cults based on "perfect" shapes hadn't done all the [gestures] that they did
divine geometry is a helluva drug
@aeva on the other hand getting extremely horny for triangles is both funny and kinda relatable, so
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@aeva a lot of things would be simpler if cults based on "perfect" shapes hadn't done all the [gestures] that they did
divine geometry is a helluva drug
@SnoopJ we're still using spherical trig in astronomy today despite earth being an ellipsoid
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@aeva on the other hand getting extremely horny for triangles is both funny and kinda relatable, so
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@SnoopJ we're still using spherical trig in astronomy today despite earth being an ellipsoid
@aeva well, yea, because astronomy doesn't really give a shit what shape the earth is anyway
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@aeva well, yea, because astronomy doesn't really give a shit what shape the earth is anyway
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Gli ultimi otto messaggi ricevuti dalla Federazione
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@dan that's smart, because you'll 100% sleep after a long flight.
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@Gina For me it's either at least a two night layover somewhere or ensure I land at destination in the evening to deal with jetlag, even if it's more expensive and with a worse airline.
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Also, choosing Bangkok for a 3 day layover from Sydney to Amsterdam may have been the best idea I've had in my life.
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@aeva @SnoopJ the use of "Current*", which I always have a quick "ugh" about, really sealed it for me.
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I need you all to pray for me. 🙏
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@SnoopJ :D ty
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@aeva I read too quickly and didn't realize you'd painted this. Nice job!!
