今天翻译了一段经典的贪吃蛇代码，译后感觉还有很多地方不太妥当，很多不妥的地方希望大家多指教...
原文：
//--- Flash MX Snake Game 1Kb by Strille. Version 2.2, 746 bytes
//--- Paste this code on frame 1 and set scene size to 512x280 and Frame Rate to 16
//--- The code is not written with speed in mind, only small file size. Not that it is slow :-)
createTextField("t", 1, 1, 255, 511, 32); // create a text field to write score and instructions
t.text = "Snake Game/t-/tPress SPACE"; // show start text
beginFill(0xeeeeee); lineStyle(1); lineTo(511, 0); lineTo(511, 256); lineTo(0, 256); endFill(); // draw background with border
Key.addListener(t); // use an existing object as key listener (we don’t waste bytes by creating a new object)
t.onKeyDown = function() { // define an anonymous method to execute when a key is pressed
c = Key.getCode()-37; // get key code (c is a variable used "locally" several times)
if (!(c>>2)) { // arrow keys pressed (c = 0, 1, 2 or 3)
if (c != q[0]) // only add to the queue if it is a new direction
q.unshift(c);
return; // save the turn in the queue and exit method
}
// SPACE or another key other than an arrow key has been pressed
x = 32*8 + 32*520; // snake start pos (left and right side of + can be viewed as x and y coord
q = []; // a queue to store key presses (so that x number of key presses during one frame are spread over x number of frames)
m = []; // create an array to store food pos and snake
createEmptyMovieClip("s", w=0); // create MC to store the snake and the food MC and reset snake counter(w)
e = 2*(m[x-520] = 2*(r=1)); // set erase counter (e) to 4, set current direction (r) to up (1) and set food on the position the snake will be over the first time to place food
onEnterFrame = function () { // MAIN function
c = q.pop(); // pick the next turn in the queue (may be undefined if queue is empty)
if (c%2 != r%2) // and check that it is not undefined and not a 180 degree turn (annoying to be able to turn into the snake with one key press)
if (c != undefined)
r = c; // change current direction to the new value
x += [-1, -65, 1, 65][r]*8; // move the snake to a new x position (-1 = left, -65 = up, 1 = right, 65 = down)
if (m[x] == 1 or !(x%520) or !(int(x/520) % 33)) { // GAME OVER if it is a snake block or outside the map on the next position
delete onEnterFrame; // quit looping main function
t.text += "/tGAME OVER!"; return; // type game over text and exit main
}
with(s.createEmptyMovieClip(w, w)) { // place a snake block (or food block the first loop)
beginFill(255<<16); // red food color first time
if (w++) // blue snake color the other times
beginFill(0x555588);
_x = x%520; _y = int(x/520)*8; // set snake block position
lineTo(-7, 0); lineTo(-7, -7); lineTo(0, -7); endFill(); // draw a square
}
m[x] += 1; // set current pos as "occupied" by a snake block
if (m[x] == 3) { // check if there is a food block on the new pos
t.text = "Score: " +(w-(e-=5)-2)*2; // delay erase counter with 5 (the snake will grow 5 blocks each time), calculate and type score (+10p for a food block)
do {} while (m[c = (s[0]._x = 8+random(64)*8)+(s[0]._y = 8+random(32)*8)*65]); // pick a free spot to place the food, save that number, place the food MC
m[c] = 2; // set the position picked on the line above to 2
}
if (e) { // if not food MC (s[0]) then erase last snake MC and entry in array m
c = s[e]; // get last MC
delete m[c._x+65*c._y]; removeMovieClip(c); // delete the value in the array m and delete the MC
}
e++; // increase erase snake counter
}
}
翻译：
//--- Flash MX 贪吃蛇游戏(1Kb) 制作Strille. 版本 2.2, 共计 746 字节
//--- 复制以下代码在主场景的第一帧场景大小为 512x280 , FPS 16
createTextField("t", 1, 1, 255, 511, 32);
// create a text field to write score and instructions
// 创建一个文本框用于输出成绩和指示
t.text = "Snake Game/t-/tPress SPACE";
// 显示开始信息
beginFill(0xeeeeee); lineStyle(1); lineTo(511, 0); lineTo(511, 256); lineTo(0, 256); endFill();
// 沿边框绘制背景
Key.addListener(t);
// 使用一个已存在的Object 作键盘帧听 (就样就不用再创建新Obejct，从而节约了空间)
t.onKeyDown = function() {
// 当键盘按下后，去执行自定义的这个方法
c = Key.getCode()-37;
// 获得按键的ASCII码 (变量 c 每次获取相对的ASCII码)
if (!(c>>2)) {
// 方向键的表示 (c = 0, 1, 2 or 3)
if (c != q[0])
// 只将新的方向键存入队列 q
q.unshift(c);
return;
// 在队列中保存，并结束该方法(函数)
}
// 空格或其它键不同于按下的方向键
x = 32*8 + 32*520;
// 蛇的起点坐标( 左边 + 右边：可被视为 x、y 坐标)
q = [];
// 用于存储按键的队列(因此改变在一帧中的X坐标对于所有帧中的X坐标都起作用)
m = [];
// 创建一个数组用于存储食物的坐标和蛇
createEmptyMovieClip("s", w=0);
// 创建一个空影片用于存储蛇和食物的影片剪辑，并重置蛇的计数器(w)
e = 2*(m[x-520] = 2*(r=1));
// 设置擦除计数器(e) to 4, 设置当前方向(r)为向上(1)，当蛇经过食物后立即设置食物位置为当前设置的位置
onEnterFrame = function () {
// 主函数
c = q.pop();
// 在队列中提取出下一轮变换(当队列为空时，提取数是undefined的)
if (c%2 != r%2)
// 检查其不属于undefined和180度旋转(避免任意按下一个键后就改变蛇的方向)
if (c != undefined)
r = c;
// 改变当前方向为新的方向
x += [-1, -65, 1, 65][r]*8;
// 移动蛇到一个新的X位置 (-1 = left, -65 = up, 1 = right, 65 = down)
if (m[x] == 1 or !(x%520) or !(int(x/520) % 33)) {
// 如果新的位置在蛇身上或出了边界则 GAME OVER
delete onEnterFrame;
// 退出主循环函数
t.text += "/tGAME OVER!"; return;
// 输出 GAME OVER! 并退出主程序
}
with(s.createEmptyMovieClip(w, w)) {
// 放置蛇身 (第一次循环时用于放置食物)
beginFill(255<<16);
// 首先将食物设为红色
if (w++) // blue snake color the other times
beginFill(0x555588);
_x = x%520; _y = int(x/520)*8;
// 设置蛇身的位置
lineTo(-7, 0); lineTo(-7, -7); lineTo(0, -7); endFill();
// 绘制一个方形
}
m[x] += 1;
// 设置当前位置为"已占用"区作为蛇身
if (m[x] == 3) {
// 检查是否有食物在新的位置上
t.text = "Score: " +(w-(e-=5)-2)*2;
// 延迟擦除计数器5(蛇身每次增长5), 计算并输出分数 (一个食物加10分)
do {} while (m[c = (s[0]._x = 8+random(64)*8)+(s[0]._y = 8+random(32)*8)*65]);
// 寻找一个空位置放置点, 并存储该数值, 并设置食物的影片剪辑
m[c] = 2;
//设置选出的位置为为大于2的线路上
}
if (e) {
// if not food MC (s[0]) then erase last snake MC and entry in array m
c = s[e];
// 获得最后一个影片剪辑
delete m[c._x+65*c._y]; removeMovieClip(c);
// 删除数组 m 中该元素的值并删除影片剪辑
}
e++;
// 将蛇的擦除计数器加一
}
}
