[R]Select_L_Range_2.1.jsx

//
// Author: revnart@gmail.com
// 04/2019
// L RANGE SELECTOR
//

    /*
        <javascriptresource>
        <name>[R] Select L range 2.1</name>
        <enableinfo>true</enableinfo>
        <category>Revnart</category>
        </javascriptresource>
    */

#target photoshop
var doc = app.activeDocument;

//USER INTERFACE
var myWindow = new Window ("dialog", '"L" Range');
myWindow.orientation = "column";

var inputsMin = myWindow.add ("group");
inputsMin.orientation = "row";
inputsMin.add ("statictext", undefined, "Min. value:");
var minval = inputsMin.add ("edittext", undefined, 0);
minval.characters = 10;
minval.active = true;
 
var inputsMax = myWindow.add ("group");
inputsMax.orientation = "row";
inputsMax.add ("statictext", undefined, "Max. value:");
var maxval = inputsMax.add ("edittext", undefined, 100);
maxval.characters = 10;
 
var myButtonGroup = myWindow.add ("group");
myButtonGroup.orientation = "column";
myButtonGroup.add ("button", undefined, "OK");
myButtonGroup.add ("button", undefined, "Cancel");
myWindow.show ();

//ADDITIONAL TWEAK TO SELECT ALL PIXELS WITH DESIRED "L" VALUE
var minval = Number(minval.text) - 0.1;
var maxval = Number(maxval.text) + 0.1;

//COLOR RANGE SELECTION
var idClrR = charIDToTypeID( "ClrR" );
var desc4 = new ActionDescriptor();
var idFzns = charIDToTypeID( "Fzns" );

//FUZINESS AMOUNT
desc4.putInteger( idFzns, 0 );

var idMnm = charIDToTypeID( "Mnm " );
var desc5 = new ActionDescriptor();
var idLmnc = charIDToTypeID( "Lmnc" );
desc5.putDouble( idLmnc, minval );
var idA = charIDToTypeID( "A   " );

//MINIMUM "A" VALUE
desc5.putDouble( idA, -128 );
var idB = charIDToTypeID( "B   " );

//MINIMUM "B "VALUE
desc5.putDouble( idB, -128 );

var idLbCl = charIDToTypeID( "LbCl" );
desc4.putObject( idMnm, idLbCl, desc5 );
var idMxm = charIDToTypeID( "Mxm " );
var desc6 = new ActionDescriptor();
var idLmnc = charIDToTypeID( "Lmnc" );
desc6.putDouble( idLmnc, maxval );
var idA = charIDToTypeID( "A   " );

//MAXIMUM "A" VALUE
desc6.putDouble( idA, 127 );
var idB = charIDToTypeID( "B   " );

//MAXIMUM "B" VALUE
desc6.putDouble( idB, 127 );
var idLbCl = charIDToTypeID( "LbCl" );
desc4.putObject( idMxm, idLbCl, desc6 );
var idcolorModel = stringIDToTypeID( "colorModel" );
desc4.putInteger( idcolorModel, 0 );
executeAction( idClrR, desc4, DialogModes.NO );