// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Plan an on/off cycle with soft edges
// Not compiled or tested in-world
// Setup: Put in a spare owned prim. Set positive PERIOD, ON_TIME within the period, and FADE no greater than half ON_TIME. Owner touch prints calculations only.
// Stop / restore: Disable/remove. No prim motion or appearance is changed.
// Notes: The pulse has linear fade edges. It reports intensity only and does not flicker a light.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Motion planning only.
float PERIOD=5.0;
float ON_TIME=2.0;
float FADE=0.4;
float ELAPSED=1.8;
default
{
    touch_start(integer detectedCount)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        if(PERIOD<=0.0||ON_TIME<=0.0||ON_TIME>PERIOD||FADE<=0.0||2.0*FADE>ON_TIME)
        {
            llOwnerSay("Invalid envelope timing.");
            return;
        }
        float t=ELAPSED-PERIOD*llFloor(ELAPSED/PERIOD);
        float value=0.0;
        if(t<ON_TIME)
        {
            value=1.0;
            if(t<FADE)value=t/FADE;
            else if(t>ON_TIME-FADE)value=(ON_TIME-t)/FADE;
        }
        llOwnerSay("Pulse intensity="+(string)value);
    }
}