Question

我现在在深水中。不确定我知道我在做什么！无论如何，我正在尝试为我的蛇游戏绘制地图。目前，我正在尝试添加墙，但无法正常工作！这是代码： https://editor.p5js.org/JensHaglof/sketches/YwtUO8992

或写出：

wallCount = 0
var walls = []
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
walls.push([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
function setup() {
  createCanvas(400, 400);

  for (let i = 0; i < 20; i++){
    for (let j = 0 ; j < 20 ; j++){
      if (walls[i][j] == 1){
        walls[i][j] = new Wall(walls[i]*20, walls[j]*20);
        wallCount = wallCount + 1
      }
      }
}
}

function Wall(x, y){
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);

  this.display = function(){
  fill(255, 255, 0);
  rect(this.x, this.y, 20, 20);
  }
}

function draw() {

  background(0);
  for (let i = 0 ; i < wallCount ; i++){
    for (let j = 0 ; j < wallCount ; j++){
    walls[i][j].display();
  }
  }

}

我收到错误消息“ TypeError：walls [i] [j]。显示不是函数（草图：第52行）”

我不知道从哪里开始。我正在尝试很多事情，但是就像我在黑暗中拍摄一样。有人知道怎么了吗？ /简

Answer 1

您仅初始化数组中1的位置，但是您的代码期望整个二维数组包含Wall的实例。

在不了解自己在做什么的情况下，您需要检查每个对象是否都是wall的实例

if (walls[i][j] instanceof Wall) {
  walls[i][j].display();
}

Answer 2

问题是您试图从walls数组中获取墙，该数组也包含零（命名错误）。根据您的设计，不能保证第一面墙位于[0][0]

您应该只为墙壁创建一个单独的数组：

var wallList = [];
var walls = [];

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

  for (let i = 0; i < walls.length; i++) {
    for (let j = 0; j < walls.length; j++) {
      if (walls[i][j] == 1) {
        walls[i][j] = new Wall(walls[i] * 20, walls[j] * 20);
        wallList.push(walls[i][j]);
      }
    }
  }
}

function Wall(x, y) {
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);

  this.display = function() {
    fill(255, 255, 0);
    rect(this.x, this.y, 20, 20);
  }
}

function draw() {
  background(0);
  for (let i = 0; i < wallList.length; i++) {
    wallList[i][j].display();
  }
}

或者，您应该先遍历所有项目，然后检查每个项目是否都是一堵墙，然后再继续：

var walls = [];

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

  for (let i = 0; i < walls.length; i++) {
    for (let j = 0; j < walls.length; j++) {
      if (walls[i][j] == 1) {
        walls[i][j] = new Wall(walls[i] * 20, walls[j] * 20);
      }
    }
  }
}

function Wall(x, y) {
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);

  this.display = function() {
    fill(255, 255, 0);
    rect(this.x, this.y, 20, 20);
  }
}

function draw() {
  background(0);
  for (let i = 0; i < walls.length; i++) {
    for (let j = 0; j < walls.length; j++) {
      if(walls[i][j] instanceof Wall) walls[i][j].display();
    }
  }
}

Answer 3

这不是解决问题的方法，但是您仍然应该做一些事情。重构此功能

function Wall(x, y){
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);

  this.display = function(){
  fill(255, 255, 0);
  rect(this.x, this.y, 20, 20);
  }
}

进入

function Wall(x, y){
  this.x = x;
  this.y = y;
  rect(this.x, this.y, 20, 20);
}

Wall.prototype.display = function() {
  fill(255, 255, 0);
  rect(this.x, this.y, 20, 20);
}

在您的原始代码中，对Wall构造函数的每次调用都会创建一个新的独立（尽管彼此相同）display函数，这在性能上是很糟糕的。请改用函数原型。

无法将功能识别为功能？

3 个答案: