// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Inspect a bounded PID control step
// Not compiled or tested in-world
// Setup: Place in a spare owned prim. Touch repeatedly to feed the next predefined measurement. Touch for owner-only output.
// Stop / restore: Remove/disable. The script calculates only; no scene properties change.
// Notes: A teaching controller with fixed sample time, not a ready physics controller. Real control needs measured dt, reset handling and tuning.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT. Planning only.
list MEASUREMENTS=[0.0,0.4,0.7,0.9,1.1,1.0];
integer cursor;
float integral;
float previousError;
integer initialized;
default
{
    touch_start(integer detectedCount)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        float measured=llList2Float(MEASUREMENTS,cursor);
        cursor=(cursor+1)%llGetListLength(MEASUREMENTS);
        float dt=0.1;
        float error=1.0-measured;
        integral+=error*dt;
        if(integral>0.5)integral=0.5;
        if(integral< -0.5)integral=-0.5;
        float derivative=0.0;
        if(initialized)derivative=(error-previousError)/dt;
        previousError=error;
        initialized=TRUE;
        float output=2.0*error+0.8*integral+0.1*derivative;
        if(output>1.0)output=1.0;
        if(output< -1.0)output=-1.0;
        llOwnerSay("Measurement="+(string)measured+" error="+(string)error+" output="+(string)output);
    }
}