// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// World-upright child preview
// Not compiled or tested in-world
// Setup: Put in nonphysical child; owner-touch previews/restores. Keep root still.
// Stop / restore: Owner-touch again to restore the startup snapshot before removal or reset, unless setup describes a different cycle. Do not relink during a preview.
// Notes: Use a spare modifiable build. Saved state lives only in script memory. Converts world orientation into root-local rotation.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Not compiled or tested in-world.
integer preview;
rotation home;
default
{
    state_entry()
    {
        home=llGetLocalRot();
    }
    touch_start(integer n)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        if(llGetLinkNumber()<2||llGetStatus(STATUS_PHYSICS))return;
        vector forward=llRot2Fwd(home*llGetRootRotation());
        forward.z=0.0;
        if(llVecMag(forward)<0.01)return;
        preview=!preview;
        if(preview)
        {
            rotation root=llGetRootRotation();
            vector f=llRot2Fwd(home*root);
            float yaw=llAtan2(f.y,f.x);
            llSetLinkPrimitiveParamsFast(LINK_THIS,[PRIM_ROT_LOCAL,llEuler2Rot(<0.0,0.0,yaw>)/root]);
        }
        else
        {
            llSetLinkPrimitiveParamsFast(LINK_THIS,[PRIM_ROT_LOCAL,home]);
        }
    }
}