期望有条件的使用，但看到了

Question

试图使圆圈停止并返回

如果还有其他循环

var elipseX = 0;

var elipseY = 0;

function setup() {
  createCanvas(400, 400);




}




function draw() {
  background(255)
  stroke(0)
  strokeWeight(6)

  fill(255,255,255,50)
  ellipse(elipseX, elipseX, 100, 100);

  elipseX = elipseX + 1
  elipseY = elipseY + 1

  if (elipseX = 399) 
  { (elipseX = elipseX -1)}



}

  if (elipseX = 399) 
  { (elipseX = elipseX -1)} this gives the error in the title

Answer 1

您缺少=状况中的一个

if (elipseX == 399) { (elipseX = elipseX -1)}

= 是一个赋值运算符

== 是比较运算符