一个拖动拼图游戏的代码小问题想不通
html代码：
<!doctype html>
Sliding Puzzle
<br> .picture {<br> border: 1px solid black;<br> }<br>Sliding Puzzle
Easy Hard
js代码：var context = document.getElementById('puzzle').getContext('2d');var img = new Image();
img.src = './img/dimetrodon.jpg';
img.addEventListener('load', drawTiles, false);var boardSize = document.getElementById('puzzle').width;
var tileCount = document.getElementById('scale').value;var tileSize = boardSize / tileCount;
var clickLoc = new Object;
clickLoc.x = 0;
clickLoc.y = 0;var emptyLoc = new Object;
emptyLoc.x = 0;
emptyLoc.y = 0;var solved = false;
var boardParts = new Object;
setBoard();document.getElementById('scale').onchange = function() {
tileCount = this.value;
tileSize = boardSize / tileCount;
setBoard();
drawTiles();
};document.getElementById('puzzle').onmousemove = function(e) {
clickLoc.x = Math.floor((e.pageX - this.offsetLeft) / tileSize);
clickLoc.y = Math.floor((e.pageY - this.offsetTop) / tileSize);
};document.getElementById('puzzle').onclick = function() {
if (distance(clickLoc.x, clickLoc.y, emptyLoc.x, emptyLoc.y) == 1) {
slideTile(emptyLoc, clickLoc);
drawTiles();
}
if (solved) {
setTimeout(function() {alert("You solved it!");}, 500);
}
};function setBoard() {
boardParts = new Array(tileCount);
for (var i = 0; i < tileCount; ++i) {
boardParts[i] = new Array(tileCount);
for (var j = 0; j < tileCount; ++j) {
boardParts[i][j] = new Object;
boardParts[i][j].x = (tileCount - 1) - i;
boardParts[i][j].y = (tileCount - 1) - j;
}
}
emptyLoc.x = boardParts[tileCount - 1][tileCount - 1].x;
emptyLoc.y = boardParts[tileCount - 1][tileCount - 1].y;
solved = false;
}请问为什么js中的emptyLoc的x和y不需要更新，或者他的x和y是怎么更新的，他代码里面emptyLoc.x和emptyLoc.y的值貌似都是2，没有变化，不更新的话没办法继续判断距离distance==1啊，为什么它程序可以正确运行，还是我理解错了？
繁华开满天机2回答
-
蝴蝶刀刀
slideTile(emptyLoc, clickLoc);在这里传入的清空位置和点击位置而 clickLoc 在你鼠标移动到某个puzzle上面，就根据它的位置确定了。document.getElementById('puzzle').onmousemove = function(e) {clickLoc.x = Math.floor((e.pageX - this.offsetLeft) / tileSize);clickLoc.y = Math.floor((e.pageY - this.offsetTop) / tileSize);}; -
偶然的你
// var a = toLoc.x;// var b = toLoc.y;toLoc.x = fromLoc.x;toLoc.y = fromLoc.y;// fromLoc.x = a;// fromLoc.y = b;//这边为什么不用给emptyLoc改变坐标？他这边只是给toLoc.x = fromLoc.x;toLoc.y = fromLoc.y;，这样更新，而没有给fromLoc也就是emptyLoc的x,y更新位置信息，emptyLoc的位置信息好像一直都是emptyLoc.x=0，emptyLoc.y=0,请问您他的信息是在哪儿更新的？
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相关分类
JavaScript