// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Sort a ring of points by bearing
// Not compiled or tested in-world
// Setup: Use a spare owned prim. Set POINTS around CENTER. Owner touch prints sample coordinates.
// Stop / restore: Remove/disable. Nothing is rezzed or moved.
// Notes: Angle sorting does not produce a valid polygon for every arbitrary point cloud; duplicate bearings and interior points need additional handling.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Planning only.
list POINTS=[<0.0,3.0,0.0>,<-3.0,0.0,0.0>,<3.0,0.0,0.0>,<0.0,-3.0,0.0>];
vector CENTER=ZERO_VECTOR;
default
{
    touch_start(integer detectedCount)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        list ordered;
        integer i;
        for(i=0;i<llGetListLength(POINTS);++i)
        {
            vector p=llList2Vector(POINTS,i)-CENTER;
            if(p.x*p.x+p.y*p.y<0.000001)
            {
                llOwnerSay("Point at center has no bearing.");
                return;
            }
            ordered+=[llAtan2(p.y,p.x),i];
        }
        ordered=llListSort(ordered,2,TRUE);
        for(i=0;i<llGetListLength(ordered);i+=2)llOwnerSay("Index="+(string)llList2Integer(ordered,i+1)+" angle="+(string)(llList2Float(ordered,i)*RAD_TO_DEG));
    }
}