function obj_calc() {
	var inp_width;
	var inp_height;
	var inp_length;
	var out_area_walls;
	var out_area_windows;
	var out_area_walls_clear;
	var inp_acq_blocks;
	var inp_man_blocks;
	var out_cost_blocks;
	var out_cost_glue;
	var out_cost_mount;
	var out_cost_out_walls;
	var btn;
	var fractionDigits=2;
	var fractionDigitsCost=0;
	this.setFractionDigits = function(num){fractionDigits=num}
	this.setFractionDigitsCost = function(num){fractionDigitsCost=num}
	this.calc = function() {_calc()}
	function _calc() {
		var width=parseFloat(inp_width.value.replace(/,/g, "."));
		var height=parseFloat(inp_height.value.replace(/,/g, "."));
		var length=parseFloat(inp_length.value.replace(/,/g, "."));
		if (!isNaN(width) && !isNaN(height) && !isNaN(length)) {
			var area_walls = (width+length)*height*2;
			var area_windows = area_walls*10/100;
			var area_walls_clear = area_walls - area_windows;
			var cost_blocks = (inp_acq_blocks.checked)? 2615 : 1125;
			var cost_glue = area_walls_clear*200;
			var cost_mount = area_walls_clear*1000;
			var cost_out_walls = area_walls_clear*cost_blocks+cost_glue+cost_mount;
			
			out_area_walls.innerHTML=area_walls.toFixed(fractionDigits);
			out_area_windows.innerHTML=area_windows.toFixed(fractionDigits);
			out_area_walls_clear.innerHTML=area_walls_clear.toFixed(fractionDigits);
			out_cost_blocks.innerHTML=cost_blocks.toFixed(fractionDigitsCost);
			out_cost_glue.innerHTML=cost_glue.toFixed(fractionDigitsCost);
			out_cost_mount.innerHTML=cost_mount.toFixed(fractionDigitsCost);
			out_cost_out_walls.innerHTML=cost_out_walls.toFixed(fractionDigitsCost);
		}
		else {
			out_area_walls.innerHTML="000";
			out_area_windows.innerHTML="000";
			out_area_walls_clear.innerHTML="000";
			out_cost_blocks.innerHTML="000";
			out_cost_glue.innerHTML="000";
			out_cost_mount.innerHTML="000";
			out_cost_out_walls.innerHTML="000";	
		}
	}
	this.setWidthInput = function(id) {inp_width=document.getElementById(id)}
	this.setHeightInput = function(id) {inp_height=document.getElementById(id)}
	this.setLengthInput = function(id) {inp_length=document.getElementById(id)}
	this.setAcqBlocksInput = function(id) {inp_acq_blocks=document.getElementById(id);inp_acq_blocks.checked=true;}
	this.setManBlocksInput = function(id) {inp_man_blocks=document.getElementById(id)}
	
	this.setAreaWallsOutput = function(id) {out_area_walls=document.getElementById(id)}
	this.setAreaWindowsOutput = function(id) {out_area_windows=document.getElementById(id)}
	this.setAreaWallsClearOutput = function(id) {out_area_walls_clear=document.getElementById(id)}
	
	this.setCostBlocksOutput = function(id) {out_cost_blocks=document.getElementById(id)}
	this.setCostGlueOutput = function(id) {out_cost_glue=document.getElementById(id)}
	this.setCostMountOutput = function(id) {out_cost_mount=document.getElementById(id)}
	this.setCostOutWallsOutput = function(id) {out_cost_out_walls=document.getElementById(id)}
	
	this.setBtn = function(id) {
		btn=document.getElementById(id)
		btn.onclick=function() {_calc();}
	}
}