我是一個總體初學者,編碼一般。這也是我第一次嘗試用js做些事情;我想動畫一堆正方形移動到頁面上的某個點。我搜索了一堆東西,我寫了這個,但它不起作用。有人可以告訴我爲什麼這不起作用嗎?Javascript基本動畫
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var enemies =[];
for (var i = 0; i < 10; i++){
var randomX = Math.abs(Math.random());
var randomY = Math.abs(Math.random());
if (randomX > 100 && randomX < 1200){
if (randomX%2 == 0){
randomX = 140;
} else {
randomX = 1281;
}
}
if (randomY > 100 && randomY < 75){
if (randomY%2 == 0){
randomY = 15;
} else{
randomY = 560;
}
}
var enemy = new Enemy(randomX,randomY,0,0);
enemies.push(enemy);
}
var Enemy = function(x,y,velx,vely){
this.x = x;
this.y = y;
this.velx = 0;
this.vely = 0;
}
Enemy.prototype.update = function(){
var tx = 650 - this.x;
var ty = 250 - this.y;
var dist = Math.sqrt(tx*tx + ty*ty);
this.velx = (tx/dist);
this.vely = (ty/dist);
if (dist > 0){
this.x += this.velx;
this.y += this.vely;
}
};
Enemy.prototype.render = function(){
context.fillStyle = #000000;
context.rect(this.x,this.y,25,25);
context.fill();
};
function render(){
context.clearRect(0,0,canvas.width,canvas.height);
for (var i = 0; i < enemies.length; i++){
var one = enemies[i];
context.clearRect(one.x,one.y,25,25);
one.update();
one.render();
}
requestAnimationFrame(render);
}
render();
context.fillStyle ='#000000'; - 在這裏添加引號,並重新嘗試.... – sinisake
謝謝,我完全錯過了!但它仍然不起作用:( – imhappi
你實際看到了什麼樣的結果?你能更具體地瞭解什麼是或不在工作嗎 –