// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Classify points around a plane
// Not compiled or tested in-world
// Setup: Use a spare owned prim. Set NORMAL, ON_PLANE, POINTS and TOLERANCE. Touch for owner-only results.
// Stop / restore: Disable/remove. No scene properties change.
// Notes: Normal direction determines positive side; the tolerance is measured in coordinate distance units.
// License: see LICENSE in this distribution.
// Original Incoprea. MIT.
vector NORMAL=<0.0,0.0,1.0>;
vector ON_PLANE=<0.0,0.0,2.0>;
float TOLERANCE=0.01;
list POINTS=[<1.0,2.0,3.0>,<1.0,1.0,2.005>,<0.0,0.0,0.0>];
default
{
    touch_start(integer detectedCount)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        if(llVecMag(NORMAL)<0.000001||TOLERANCE<0.0)
        {
            llOwnerSay("Invalid normal/tolerance.");
            return;
        }
        vector n=llVecNorm(NORMAL);
        integer i;
        for(i=0;i<llGetListLength(POINTS);++i)
        {
            float d=(llList2Vector(POINTS,i)-ON_PLANE)*n;
            string side="on plane";
            if(d>TOLERANCE)side="positive side";
            else if(d< -TOLERANCE)side="negative side";
            llOwnerSay((string)i+": "+side+" distance="+(string)d);
        }
    }
}