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  4. 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

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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  • aevaundefined aeva

    @jon_valdes @dotstdy it's bizarre seeing my 10 year old telephone's mali do better at... anything at all

    aevaundefined Questo utente è esterno a questo forum
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    aeva
    scritto su ultima modifica di
    #19

    @jon_valdes @dotstdy though I guess the corner the intel case is cutting is where the slope starts to level out so I guess that makes sense. are CPU trig functions just as bad?

    aevaundefined 1 Risposta Ultima Risposta
    • aevaundefined aeva

      @jon_valdes @dotstdy though I guess the corner the intel case is cutting is where the slope starts to level out so I guess that makes sense. are CPU trig functions just as bad?

      aevaundefined Questo utente è esterno a questo forum
      aevaundefined Questo utente è esterno a questo forum
      aeva
      scritto su ultima modifica di
      #20

      @jon_valdes @dotstdy would mollytime get a warmer, fuller sound if i switched to expensive software sine waves :3

      Josh Simmonsundefined 1 Risposta Ultima Risposta
      • aevaundefined aeva

        @jon_valdes @dotstdy would mollytime get a warmer, fuller sound if i switched to expensive software sine waves :3

        Josh Simmonsundefined Questo utente è esterno a questo forum
        Josh Simmonsundefined Questo utente è esterno a questo forum
        Josh Simmons
        scritto su ultima modifica di
        #21

        @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.

        aevaundefined 1 Risposta Ultima Risposta
        • aevaundefined aeva

          @jon_valdes @dotstdy my laptop has a recent-ish Xe gpu

          Jon Valdésundefined Questo utente è esterno a questo forum
          Jon Valdésundefined Questo utente è esterno a questo forum
          Jon Valdés
          scritto su ultima modifica di
          #22

          @aeva @dotstdy Yup! I was using trig to calculate screen positions for the stars. And as the skydome rotates, when the sin/cos of some stars happened to cross those bright lines you're seeing, they'd first slow down, and then jump over a very specific line in the sky. Was great 🙄

          aevaundefined 1 Risposta Ultima Risposta
          • Jon Valdésundefined Jon Valdés

            @aeva @dotstdy Yup! I was using trig to calculate screen positions for the stars. And as the skydome rotates, when the sin/cos of some stars happened to cross those bright lines you're seeing, they'd first slow down, and then jump over a very specific line in the sky. Was great 🙄

            aevaundefined Questo utente è esterno a questo forum
            aevaundefined Questo utente è esterno a questo forum
            aeva
            scritto su ultima modifica di
            #23

            @jon_valdes @dotstdy 😧

            1 Risposta Ultima Risposta
            • Josh Simmonsundefined Josh Simmons

              @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.

              aevaundefined Questo utente è esterno a questo forum
              aevaundefined Questo utente è esterno a questo forum
              aeva
              scritto su ultima modifica di
              #24

              @dotstdy @jon_valdes maybe I'll call the expensive exact soft sin oscillator "gold plated sin" 🤔

              demofoxundefined 1 Risposta Ultima Risposta
              • aevaundefined aeva

                @dotstdy @jon_valdes maybe I'll call the expensive exact soft sin oscillator "gold plated sin" 🤔

                demofoxundefined Questo utente è esterno a questo forum
                demofoxundefined Questo utente è esterno a questo forum
                demofox
                scritto su ultima modifica di
                #25

                @aeva @dotstdy @jon_valdes start a new genre "deca-dance"

                aevaundefined 1 Risposta Ultima Risposta
                • demofoxundefined demofox

                  @aeva @dotstdy @jon_valdes start a new genre "deca-dance"

                  aevaundefined Questo utente è esterno a questo forum
                  aevaundefined Questo utente è esterno a questo forum
                  aeva
                  scritto su ultima modifica di
                  #26

                  @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

                  aevaundefined 1 Risposta Ultima Risposta
                  • aevaundefined aeva

                    @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

                    aevaundefined Questo utente è esterno a questo forum
                    aevaundefined Questo utente è esterno a questo forum
                    aeva
                    scritto su ultima modifica di
                    #27

                    @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

                    Tom Forsythundefined 1 Risposta Ultima Risposta
                    • aevaundefined aeva

                      @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

                      Tom Forsythundefined Questo utente è esterno a questo forum
                      Tom Forsythundefined Questo utente è esterno a questo forum
                      Tom Forsyth
                      scritto su ultima modifica di
                      #28

                      @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).

                      Tom Forsythundefined 1 Risposta Ultima Risposta
                      • Tom Forsythundefined Tom Forsyth

                        @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).

                        Tom Forsythundefined Questo utente è esterno a questo forum
                        Tom Forsythundefined Questo utente è esterno a questo forum
                        Tom Forsyth
                        scritto su ultima modifica di
                        #29

                        @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.

                        aevaundefined 1 Risposta Ultima Risposta
                        • Tom Forsythundefined Tom Forsyth

                          @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.

                          aevaundefined Questo utente è esterno a questo forum
                          aevaundefined Questo utente è esterno a questo forum
                          aeva
                          scritto su ultima modifica di
                          #30

                          @TomF @demofox @dotstdy @jon_valdes I already do the range reduction. I learned that the hard way once upon a time XD

                          1 Risposta Ultima Risposta
                          • aevaundefined aeva

                            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: 😏

                            aevaundefined Questo utente è esterno a questo forum
                            aevaundefined Questo utente è esterno a questo forum
                            aeva
                            scritto su ultima modifica di
                            #31

                            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?

                            https://en.wikipedia.org/wiki/Geographic_coordinate_system

                            https://en.wikipedia.org/wiki/Equatorial_coordinate_system

                            aevaundefined 1 Risposta Ultima Risposta
                            • aevaundefined aeva

                              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?

                              https://en.wikipedia.org/wiki/Geographic_coordinate_system

                              https://en.wikipedia.org/wiki/Equatorial_coordinate_system

                              aevaundefined Questo utente è esterno a questo forum
                              aevaundefined Questo utente è esterno a questo forum
                              aeva
                              scritto su ultima modifica di
                              #32

                              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

                              aevaundefined 1 Risposta Ultima Risposta
                              • aevaundefined aeva

                                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

                                aevaundefined Questo utente è esterno a questo forum
                                aevaundefined Questo utente è esterno a questo forum
                                aeva
                                scritto su ultima modifica di
                                #33

                                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

                                rfundefined SnoopJundefined aevaundefined 3 Risposte Ultima Risposta
                                • aevaundefined aeva

                                  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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                                  rfundefined Questo utente è esterno a questo forum
                                  rf
                                  scritto su ultima modifica di
                                  #34

                                  @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?

                                  https://www.youtube.com/watch?v=YdOXS_9_P4U

                                  aevaundefined 1 Risposta Ultima Risposta
                                  • aevaundefined aeva

                                    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

                                    SnoopJundefined Questo utente è esterno a questo forum
                                    SnoopJundefined Questo utente è esterno a questo forum
                                    SnoopJ
                                    scritto su ultima modifica di
                                    #35

                                    @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

                                    SnoopJundefined aevaundefined 2 Risposte Ultima Risposta
                                    • rfundefined rf

                                      @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?

                                      https://www.youtube.com/watch?v=YdOXS_9_P4U

                                      aevaundefined Questo utente è esterno a questo forum
                                      aevaundefined Questo utente è esterno a questo forum
                                      aeva
                                      scritto su ultima modifica di
                                      #36

                                      @rf they were so close lol

                                      1 Risposta Ultima Risposta
                                      • SnoopJundefined SnoopJ

                                        @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

                                        SnoopJundefined Questo utente è esterno a questo forum
                                        SnoopJundefined Questo utente è esterno a questo forum
                                        SnoopJ
                                        scritto su ultima modifica di
                                        #37

                                        @aeva on the other hand getting extremely horny for triangles is both funny and kinda relatable, so

                                        aevaundefined 1 Risposta Ultima Risposta
                                        • SnoopJundefined SnoopJ

                                          @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

                                          aevaundefined Questo utente è esterno a questo forum
                                          aevaundefined Questo utente è esterno a questo forum
                                          aeva
                                          scritto su ultima modifica di
                                          #38

                                          @SnoopJ we're still using spherical trig in astronomy today despite earth being an ellipsoid

                                          SnoopJundefined 1 Risposta Ultima Risposta
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                                          Gli ultimi otto messaggi ricevuti dalla Federazione
                                          • aevaundefined
                                            aeva

                                            now that I'm a bit further down this rabbit hole I'm realizing this isn't much different from the terrestrial cartography I did one summer in college about 16 years ago, except that your benchmarks are all moving a lot faster

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                                          • Evan Prodromouundefined
                                            Evan Prodromou

                                            @ok That's what I thought.

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                                          • Evan Prodromouundefined
                                            Evan Prodromou

                                            Bot server is here: https://github.com/evanp/activitypub-bot and you can ask @ok if they are OK

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                                          • Evan Prodromouundefined
                                            Evan Prodromou

                                            The update was hard; the jsonld.js library was choking on the FEP's context document because Codeberg Pages, where FEP context documents are hosted, is unreliable.

                                            I ended up adding a feature to the `activitystrea.ms` NodeJS library to let you pre-cache a context document, so it didn't have to go fetch it at run time. While I was under the hood, I also fixed a couple of bugs that made it hard to work with extra context documents.

                                            The bot server is now working; I'm going to add more contexts.

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                                          • Evan Prodromouundefined
                                            Evan Prodromou

                                            I updated the #ActivityPubBot server software to use FEP-5711, the inverse properties FEP. It is a way to declare two-way relations; if X has an `inbox` property with value Y, then Y has an `inboxOf` property with value X. It helps with navigation when you're using the ActivityPub API, and it also helps with spoofing (since both objects agree on the relationship).

                                            https://w3id.org/fep/5711

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                                          • Evan Prodromouundefined
                                            Evan Prodromou

                                            @lkngrrr are you on the plane right now?

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                                          • lkngrrr 🏳️‍🌈🏳️‍⚧️🏴‍☠️undefined
                                            lkngrrr 🏳️‍🌈🏳️‍⚧️🏴‍☠️

                                            I know I am flying Air France to Paris in an Airbus 350 but WOW I was not prepared for how French this was gonna be

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                                          • L'Anarchiversitarioundefined
                                            L'Anarchiversitario

                                            Contro il ponte, contro la repressione! Solidarietà agli arrestati No Ponte (con gli indirizzi per scrivere ai compagni e indicazioni per il sostegno economico)
                                            @anarchia
                                            Riceviamo e diffondiamo: CONTRO IL PONTE, CONTRO LA REPRESSIONE SOLIDARIETÀ AD ANDRE, BAK E GUI Negli scorsi giorni trehttps://www.rivoluzioneanarchica.it/contro-il-ponte-contro-la-repressione-solidarieta-agli-arrestati-no-ponte-con-gli-indirizzi-per-scrivere-ai-compagni-e-indicazioni-per-il-sostegno-economico/

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