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    Centripetal Force

    Scheduled Pinned Locked Moved SketchyPhysics
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    • G Offline
      GoldenFrog
      last edited by

      Well, Inches per frame is a start. Perhaps you can specify how long each frame is? Because there is an option under Plugins>SketchyPhysics>Physics Settings that allows you to change the framerate. The default framerate is 3. 3 whats? Perhaps it is a real life unit?

      Thanks,

      --PinkSkink

      Remember, great minds think alike, and fools never differ.

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      • M Offline
        Mr.K.1
        last edited by

        Actually to correct myself, that code will put out whatever units you have set in your model(meters, inches, centimeters,...), this being due to SU converting units with their built in classes (points, vectors,...)

        Now the frame length depends entirely on your models framerate, best way to look that up is opening the Ruby console then running SP for about 500 frames and resetting, the readout should get you a fairly accurate FPS average.
        Then just multiply the average fps with speed and you got a unit per second value.

        The framerate setting in Physics Settings is a bit misleading because it has no direct connection to frames per second, what it defines is how many physics calculation cycles will be made before the model refreshes.
        So the default 3 means all the collisions, velocities, torques, positions,... will be calculated 3x and then the models will move.
        Setting it higher can serve as a fast forward feature, because all the objects will move by more iterations between frames.

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        • G Offline
          GoldenFrog
          last edited by

          @unknownuser said:

          Well you can display the velocity of an object by putting this code into it's Script field:
          ontick{
          vector = Geom::Vector3d.new( getVelocity )
          logLine(vector.length.to_s)
          }

          I tried selecting "OnTick" for my cone, and putting the script you wrote into the blue box that appeared below it. But it keeps saying the formula does not compile. am I doing something wrong?

          Thanks,

          --PinkSkink

          Remember, great minds think alike, and fools never differ.

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          • C Offline
            CPhillips
            last edited by

            Put the code in the Scripted field. Not the ontick field.

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            • G Offline
              GoldenFrog
              last edited by

              I hate to be so bothersome, but I can't seem to find this scripted field anywhere. 😕 Is it in the UI for the cone? Perhaps you could give me a screenshot?

              Sorry about being so annoying!

              --PinkSkink

              Remember, great minds think alike, and fools never differ.

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              • G Offline
                GoldenFrog
                last edited by

                Oh! Thanks, Jay, I need to update my Sketchyphysics, then.

                --PinkSkink

                Remember, great minds think alike, and fools never differ.

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                • G Offline
                  GoldenFrog
                  last edited by

                  Hi everyone!

                  I downloaded the latest version of SketchyPhysics, and everything works great now. I have only one problem. For things to work, my cone must be about a yard in diameter. I actually need it to be more like a few inches. But when I make it that small, the joints and things don't seem to work. It seems like SketchyPhysics is unable to sense certain objects when they are below a certain size. Is there a setting I can change to fix this?

                  Thank you,

                  PinkSkink

                  Remember, great minds think alike, and fools never differ.

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                  • C Offline
                    CPhillips
                    last edited by

                    It is a limitation of the physics engine.

                    There is a setting in the plugins->Sketchy Physics settings dialog that will allow you to adjust world scale. It is still tricky tho. Best to make models big enough so that they work with the default settings.

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                    • G Offline
                      GoldenFrog
                      last edited by

                      I see. Ok, thanks.

                      --PinkSkink

                      Remember, great minds think alike, and fools never differ.

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                      • G Offline
                        GoldenFrog
                        last edited by

                        Just a little update.

                        Everything is working great, including the worldscale, which i did get to work without glitching. However, the velocities needed to expel the ball seem about 10x too big. I'm wondering, in SketchyPhysics is the default acceleration due to gravity 9.8 m/sec^2(32 ft/sec^2), or is it something else?

                        --PinkSkink

                        Remember, great minds think alike, and fools never differ.

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                        • C Offline
                          CPhillips
                          last edited by

                          That is more or less what gravity is. All other units are not in any sort of real world scale. If 10x works then its "right".

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                          • G Offline
                            GoldenFrog
                            last edited by

                            Interesting. Thanks very much!

                            --PinkSkink

                            Remember, great minds think alike, and fools never differ.

                            1 Reply Last reply Reply Quote 0
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