Re: Programming a natural looking swing (was Repulsion between physical and other objects)

> I think the issue of timered setRot leads to jerkiness-- there's a 0.2
> second builtin script delay after you call that function, according to
> http://lslwiki.net/lslwiki/wakka.php?wakka=llSetRot
>
> So at very best you'd get five updates per second.  Not sure how good
> that would look with any degree of damping clientside.
> K
>
> On Thu, Sep 4, 2008 at 1:12 PM, G <gcanaday@...
> <mailto:gcanaday@...>> wrote:
>
>
>     Ouch, that's a lot of work. It might be easier to simply use two
>     llSetRots on a timer that's a little too short to actually
>     complete the rotation, thus relying on the built-in smoothing for
>     the direction change rather than having the abrupt stop when
>     rotation completes, since it never completes... haven't tried it
>     that way though, and there's no way to change the rotation speed
>     since the llSetRot() calls are pretty static in how long they take
>     to complete.
>
>     omg that was a long sentence.
>
>     G
>
>
>     AnnMarie@... wrote:
>
>         It is a long time since I did one and mine was a vertical
>         motion but from memory, here is an outline on how to go about it.
>
>         The program has two segments.  The first to generate a list of
>         numbers that runs only if you change swing parameters.
>         This list of numbers is used by the second program segment
>         that moves the swing.
>         For the first part that generates the data list:-
>         You decide how many steps you want to do from peak to peak on
>         the swing.
>         This can be user-setable if you want to adjust smoothness.
>         Divide 180 degrees by this number to get the step angle for
>         looking up.
>         Start at 90 degrees and step to -90 degrees (converted to
>         radians) and look up the llSin() of these angles and put them
>         in a list.
>         This will give you a list of numbers starting at +1 and ending
>         at -1.
>         You now step through this list to create a second list.
>         You need to scale and convert the numbers from +1 through -1
>         to an angle for llSetRot().
>         So +1 will correspond to the highest point on the swing, say
>         35 degrees (which can be user adjustable too).
>         zero will correspond to swing vertical
>         -1 corresponds to swing back 35 degrees, all converted to radians.
>
>         You run this segment as needed to create the working list that
>         contains the angles that are plugged into llSetRot() only on
>         rez, or when user wants to change one of the parameters.
>
>         To run the swing have it sit at half way through the list
>         (vertical) if you want it to be able to stop.
>         When it starts, step through the list using a timer set to
>         total swing time divided by the number of steps (can be user
>         adjustable).
>         You will be stepping from mid point on the list to the bottom,
>         then reverse and step through to the top, then reverse again.
>         On each step put the list angle value into llSetRot().
>
>         Although it is not physical, there is some smoothing built
>         into llSetRot() changes, they don't move instantaneoulsy so
>         experiment to find the minimum number of steps that looks
>         smooth and reduces computing overhead.
>
>         If you want to get REALLY fancy, you can let the swing
>         accelerate/decelerate on start/stop by changing the 35 degree
>         angle in increasing/decreasing steps from/to zero,
>         recalculating the angle list each time.
>
>         I'm sure the above could be written to calculate the angles on
>         the fly instead of using the list look-up but I did it this
>         way.  It is easier to understand and is probably less
>         processing load on the sim computer.
>
>         AnnMarie Otoole.
>
>
>         ----- Original Message ----- From: "G" <gcanaday@...
>         <mailto:gcanaday@...>>
>         To: <secondlifescripters@...
>         <mailto:secondlifescripters@...>>
>         Sent: Thursday, September 04, 2008 11:22 AM
>         Subject: Re: Repulsion between physical and other objects
>
>
>
>             Ann,
>
>             oo? How does that work? /me looks for example...
>
>             G
>
>
>
>
>     _______________________________________________
>     Click here to unsubscribe or manage your list subscription:
>     https://lists.secondlife.com/cgi-bin/mailman/listinfo/secondlifescripters
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> Click here to unsubscribe or manage your list subscription:
> https://lists.secondlife.com/cgi-bin/mailman/listinfo/secondlifescripters
>