Редактирование: Фрактал

{{#widget:Iframe |url = http://tm.spbstu.ru/htmlets/js2020/Borisenkov/1_zad.html | width =1300 | height = 800 | border = 0}}
==Код программы==
<div class="mw-collapsible mw-collapsed">
'''Код программы на языке JavaScript:''' <div class="mw-collapsible-content">
<syntaxhighlight lang="javascript" line start="1" enclose="div">
window.addEventListener('load',main,false);
function main () {
	var x; var y;
	var ctx = cnv.getContext('2d');
	var h = cnv.height;
	var w = cnv.width;
	var scale = 1/w;
	var a_11;var a_12;var a_21; var a_22;
	var numb1; var numb2; var decim;
	var on = false;
	var interv;
	a_11 = 1;
	a_12 = 1;
	a_21 = 1;
	a_22 = 1;
	var degrees = 0;
	var sposob;
	var clear;

	a11.onchange = function () {
		a_11 = parseFloat(document.getElementById('a11').value);
		clearInterval(interv);
		on = false;
	}
	a12.onchange = function() {
		a_12 = parseFloat(document.getElementById('a12').value);
		clearInterval(interv);
		on = false;
	}
	a21.onchange = function () {
		a_21 = parseFloat(document.getElementById('a21').value);
		clearInterval(interv);
		on = false;
	}
	a22.onchange = function () {
		a_22 = parseFloat(document.getElementById('a22').value);
		clearInterval(interv);
		on = false;
	}
	
	degree.onchange = function() {
		degrees = parseFloat(document.getElementById('degree').value);
		clearInterval(interv);
		on = false;
	}
		
	cnv.onmousedown = function () {
		var rect = cnv.getBoundingClientRect();
		x = (event.clientX - rect.left);
		y = (event.clientY - rect.top);
		clear = document.getElementsByName('clear');
		if (clear[0].checked == true) {
		ctx.clearRect(0,0,w,h);
		ctx.beginPath();
		ctx.arc(x,y,3,0,2*Math.PI);
		ctx.fillStyle = 'blue';
		ctx.fill();
		}
		if (on == false) {
			interv = setInterval(control,0.001);
			on = true;
		}
		sposob = document.getElementsByName('sposob');
		if (sposob[0].checked == true) {
			a_11 = Math.cos(degrees);
			a_22 = a_11;
			a_12 = Math.sin(degrees);
			a_21 = -a_12;
		}
		if (sposob[1].checked == true) {
			a_11 = Math.cos(degrees*2*Math.PI/360);
			a_12 = Math.sin(degrees*2*Math.PI/360);
			a_21 = -(a_12/a_11);
			a_22 = a_11 - a_21*a_12;
		}
	}
	
	function Func (numb) {
		if (numb>=0) { 
		decim = parseFloat(numb) - parseInt(numb);
	    return (decim);
		} else {
		decim = parseFloat(numb) - (parseInt(numb) - 1);
		return (decim);
		}
	}
	function coord() {
		x = (x)*scale;
		y = (y)*scale;
		sposob = document.getElementsByName('sposob');
		if (sposob[0].checked == true) { 
			numb1 = a_11*x+a_12*y;
			numb2 = a_21*x+a_22*y;
			x = Func(numb1);
			y = Func(numb2);
			console.log(1);
		}
		if (sposob[1].checked == true) {
			numb1 = a_11*x+a_12*y;
			x = Func(numb1);
			numb2 = a_21*x+a_22*y;
			y = Func(numb2);
			console.log(2);
		}
		y = y/scale;
		x = x/scale;
		console.log(x,y);
	}
	function draw() { 
		ctx.beginPath();
		ctx.rect(x,y,1,1);
		ctx.strokeStyle = 'red';
		ctx.stroke();
	}
	
	function control () {
		coord();
		draw();
	}
	
	
}
</syntaxhighlight>
</div>