// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Ellipse border length estimate
// Not compiled or tested in-world
// Setup: Place in a spare prim. Set positive semi-axes A and B. Owner touch prints results without altering the scene.
// Stop / restore: Disable or remove. No prim properties are changed.
// Notes: The result is approximate, especially for extremely flat ellipses. Semi-axes are half the overall width and height.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Owner-only calculation.
float A=5.0;
float B=3.0;
default
{
    touch_start(integer detectedCount)
    {
        if (llDetectedKey(0)!=llGetOwner()) return;
        if(A<=0.0||B<=0.0)
        {
            llOwnerSay("Positive semi-axes required.");
            return;
        }
        float h=((A-B)*(A-B))/((A+B)*(A+B));
        float perimeter=PI*(A+B)*(1.0+3.0*h/(10.0+llSqrt(4.0-3.0*h)));
        llOwnerSay("Approximate ellipse perimeter="+(string)perimeter);
    }
}