// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Find the active keyframe interval
// Not compiled or tested in-world
// Setup: Put in a spare owned prim. Set increasing TIMES and QUERY. Owner touch prints calculations only.
// Stop / restore: Disable/remove. No prim motion or appearance is changed.
// Notes: Clamps before the first and after the last frame. Real keyframed motion has additional object and parcel constraints.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Motion planning only.
list TIMES=[0.0,1.0,3.5,5.0];
float QUERY=2.0;
default
{
    touch_start(integer detectedCount)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        integer n=llGetListLength(TIMES);
        if(n<2)
        {
            llOwnerSay("Need two timestamps.");
            return;
        }
        integer i;
        for(i=1;i<n;++i)if(llList2Float(TIMES,i)<=llList2Float(TIMES,i-1))
        {
            llOwnerSay("Times must increase.");
            return;
        }
        if(QUERY<=llList2Float(TIMES,0))
        {
            llOwnerSay("At first frame.");
            return;
        }
        for(i=1;i<n;++i)
        {
            float end=llList2Float(TIMES,i);
            if(QUERY<=end)
            {
                float start=llList2Float(TIMES,i-1);
                llOwnerSay("Frames "+(string)(i-1)+" -> "+(string)i+" local t="+(string)((QUERY-start)/(end-start)));
                return;
            }
        }
        llOwnerSay("At last frame.");
    }
}