OsSlerp

//
// osSlerp Script Exemple
// Author: Kayaker Mangic Sept 2019
//
 
// This isn't the right way to wiggle a stick (llSetKeyframedMotion is better) but it does demostrate osSlerp working!
// Put this script in a prim that is long in the X direction, it will wave it's tip around in a figure 8 (infinity) pattern.
 
rotation lastrot;   // slerp between these two rotations
rotation nextrot;   // slerp between these two rotations
float t = 0.0;      // parameter for calculating angles to slerp between
float ratio = 1.0;  // does 10 slerp steps of 0.1 between last and next
integer switch;
 
default
{
    state_entry()
    {
        llSay(PUBLIC_CHANNEL, "Touch to see osSlerp usage.");
    }
 
    touch_start(integer number)
    {
        if (switch = !switch)
        {
            llSetTimerEvent(1.0);
        }
 
        else
        {
            llSetTimerEvent(0.0);
        }
    }
 
    timer()
    {
        integer counter = 10;
 
        while(--counter)
        {
            ratio += 0.1;
 
            if (ratio > 1.0)
            {
                ratio = 0.1;                                    // start over
                lastrot = nextrot;                              // save the last rotation
                t += PI / 10.0;                                 // bump t to generate points on a Lissajous curve
                float y = llSin(t);                             // this will generate points around an
                float z = llSin(2.0 * t);                       // infinity sympol
                vector fwd = llVecNorm(<2.0, y, z>);            // tip of this vector carves out the shape
                vector lft = llVecNorm(<0.0, 0.0, 1.0> % fwd);  // convert that into a rotation
                nextrot = llAxes2Rot(fwd, lft, fwd % lft);      // this will be the next rotation to slerp to
            }
 
            rotation rot = osSlerp(lastrot, nextrot, ratio);    // slerp generates rotations between these
            llSetLinkPrimitiveParamsFast(LINK_THIS, [PRIM_ROTATION, rot]);                         
            llSleep(0.09);
        }
    }
}