функция main_canvas_click не возращает значение переменной

Добрый день.
Объявил глобальную переменную var select_variable = 0;
в теле функции main_canvas_click значение переменной select_variable меняется.
В еще одной функции стоит проверка переменной, но переменная все равно остается 0

"use strict"
var select_variable    = 0;
// register the application module
b4w.register("Computer_configurator_main", function(exports, require) {

// import modules used by the app
var m_app       = require("app");
var m_cfg       = require("config");
var m_data      = require("data");
var m_preloader = require("preloader");
var m_ver       = require("version");

var m_cont      = require("container");
var m_mouse     = require("mouse");
var m_scenes    = require("scenes");
var m_anim      = require("animation");
var m_geom      = require("geometry");
var m_obj       = require("objects");
var m_ln        = require("logic_nodes");

var _previous_selected_obj = null;
var comp_cpu                   = null;
	var comp_cooler            = null;
	var comp_matherboard       = null;
	var comp_grapcic_card      = null;
	var comp_ram      		   = null;
	var comp_ssd      		   = null;
	var comp_hhd      		   = null;
	var comp_power       	   = null;
	var comp_sd                = null;
	var comp_housing           = null;
    
   


// detect application mode
var DEBUG = (m_ver.type() == "DEBUG");

// automatically detect assets path
var APP_ASSETS_PATH = m_cfg.get_assets_path("Computer_configurator");

/**
 * export the method to initialize the app (called at the bottom of this file)
 */
exports.init = function() {
    m_app.init({
        canvas_container_id: "main_canvas_container",
        callback: init_cb,
        show_fps: DEBUG,
        console_verbose: DEBUG,
        autoresize: true
    });
}

/**
 * callback executed when the app is initialized 
 */
function init_cb(canvas_elem, success) {

    if (!success) {
        console.log("b4w init failure");
        return;
    }

    m_preloader.create_preloader();

    // ignore right-click on the canvas element
    canvas_elem.oncontextmenu = function(e) {
        e.preventDefault();
        e.stopPropagation();
        return false;

    };

    load();
}

/**
 * load the scene data
 */
function load() {
    m_data.load(APP_ASSETS_PATH + "Computer_configurator.json", load_cb, preloader_cb);
}

/**
 * update the app's preloader
 */
function preloader_cb(percentage) {
    m_preloader.update_preloader(percentage);
}

/**
 * callback executed when the scene data is loaded
 */

function load_cb(data_id, success) {
   
    if (!success) {
        console.log("b4w load failure");
        return;
    }
	
m_app.enable_camera_controls();
    // place your code here
	var canvas_elem = m_cont.get_canvas();
    canvas_elem.addEventListener("mousedown", main_canvas_click, false);
	document.getElementById("btn_one").onclick = select_details_one;	
	document.getElementById("btn_two").onclick = select_details_two;
	document.getElementById("btn_three").onclick = select_details_three;

}

function main_canvas_click(e)
{   
    if (e.preventDefault)
    e.preventDefault();
    var x = m_mouse.get_coords_x(e);
    var y = m_mouse.get_coords_y(e);
	var obj = m_scenes.pick_object(x, y);
	var comp_cpu                     = m_scenes.get_object_by_name("Cicle_cpu");
	var comp_cooler                  = m_scenes.get_object_by_name("Cicle_cooler");
	var comp_matherboard             = m_scenes.get_object_by_name("Circle_matherboard");
	var comp_grapcic_card            = m_scenes.get_object_by_name("circle_grapcic_card");
	var comp_ram      		         = m_scenes.get_object_by_name("Circle_ram");
	var comp_ssd      		         = m_scenes.get_object_by_name("Circle_ssd");
	var comp_hhd      		         = m_scenes.get_object_by_name("Circle_hhd");
	var comp_power       	         = m_scenes.get_object_by_name("Circle_power");
	var comp_sd                      = m_scenes.get_object_by_name("Circle_sd");
	var comp_housing                 = m_scenes.get_object_by_name("Computer");
	switch (obj)
	{
		case comp_cpu:
		case comp_cooler:
		case comp_matherboard:
		case comp_grapcic_card:
		case comp_ram:
		case comp_ssd:
		case comp_hhd:
		case comp_power:
		case comp_sd:
		case comp_housing:   
		document.getElementById("details").style.display = "block";	
		document.getElementById("clarification").style.display = "block";
		break;
		default:
		document.getElementById("details").style.display = "none";	
		document.getElementById("clarification").style.display = "none";
	}
	switch (obj)
	{
		case comp_cpu:
		document.getElementById("text_accessories").innerHTML =  "CPU";
		document.getElementById("text_clarification").innerHTML =  "CPU";
		document.getElementById("btn_one").innerHTML = "<img src='image/intel.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/radeon.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		select_variable = 1;
		break;
		case comp_cooler:
		document.getElementById("text_accessories").innerHTML = "Cooler";
		document.getElementById("text_clarification").innerHTML =  "Cooler";
		document.getElementById("btn_one").innerHTML = "<img src='image/thermaltake.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/cooler_asterair.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		break;
		case comp_matherboard:
		document.getElementById("text_accessories").innerHTML = "Matherboard";
		document.getElementById("text_clarification").innerHTML =  "Matherboard";
		document.getElementById("btn_one").innerHTML = "<img src='image/matherboard_one.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/matherboard_two.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='image/matherboard_three.png' style='margin-left: -3px;'>";
		break;
		case comp_grapcic_card:
		document.getElementById("text_accessories").innerHTML = "Graphics card";
		document.getElementById("text_clarification").innerHTML =  "Graphics card";
        document.getElementById("btn_one").innerHTML = "<img src='image/nvidia_logo.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/asus_logo.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='image/amd-logo.png' style='margin-left: -3px;'>";
		break;
		case comp_ram:
		document.getElementById("text_accessories").innerHTML = "RAM";
		document.getElementById("text_clarification").innerHTML =  "RAM";
		document.getElementById("btn_one").innerHTML = "<img src='image/ram_one.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/ram_two.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='image/ram_three.png' style='margin-left: -3px;'>";
		break;
		case comp_ssd:
		document.getElementById("text_accessories").innerHTML = "SSD";
		document.getElementById("text_clarification").innerHTML =  "SSD";
		document.getElementById("btn_one").innerHTML = "<img src='' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		break;
		case comp_hhd:
		document.getElementById("text_accessories").innerHTML = "HHD";
		document.getElementById("text_clarification").innerHTML =  "HHD";
		document.getElementById("btn_one").innerHTML = "<img src='' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		break;
		case comp_power:
		document.getElementById("text_accessories").innerHTML = "Power suppy";
		document.getElementById("text_clarification").innerHTML =  "Power";
		document.getElementById("btn_one").innerHTML = "<img src='image/power_draft.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='image/power_draft_two.png' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		break;
		case comp_sd:
		document.getElementById("text_accessories").innerHTML = "CD";
		document.getElementById("text_clarification").innerHTML =  "CD";
		document.getElementById("btn_one").innerHTML = "<img src='image/dvd_rom.png' style='margin-left: -3px;'>";
		document.getElementById("btn_two").innerHTML = "<img src='' style='margin-left: -3px;'>";
		document.getElementById("btn_three").innerHTML = "<img src='' style='margin-left: -3px;'>";
		break;
		default:
	}

}

function select_details_one()
{   
	if ( select_variable == 1)
		{
			document.getElementById("text_clarification").innerHTML =  "1";	
		}
	else ( select_variable != 1)
		{
			document.getElementById("text_clarification").innerHTML =  "0";	
		}
}

function select_details_two()
{
	document.getElementById("text_clarification").innerHTML =  "2";	
}
function select_details_three()
{
	document.getElementById("text_clarification").innerHTML =  "3";	
}

});



// import the app module and start the app by calling the init method
b4w.require("Computer_configurator_main").init();
	

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