在这里,我试图在画布上绘制图像(图像是瓦片)。但是,我已经检查过,循环工作正常,代码正在执行,情况正确(我通过将日志文本记录到控制台进行测试),但是控制台上没有任何内容正在绘制。图像正在加载很好。Javascript不在画布上绘图
我真的不知道究竟是什么导致了这个问题,控制台上没有语法错误。以下是我的代码,任何人都可能需要一点时间来分析它,但非常感谢任何帮助。
这是在下面的脚本所定义的图像 “monsterTileSheet.png”:
var canvas = document.querySelector("canvas");
var drawingSurface = canvas.getContext("2d");
var image = new Image();
image.src = "monsterTileSheet.png";
image.addEventListener("load", loadHandler, false);
var spaceInc = 0; // increment counter
var inc = 5; // increment between the tiles
var imgSize = 80;
var map = [
[0, 0, 1, 0],
[0, 0, 0, 0],
[0, 0, 0, 0]
];
function adjustCanvas() {
canvas.height = (map.length * imgSize) + (map.length * inc);
canvas.width = (map[0].length * imgSize) + (map[0].length * inc);
}
var monster = {
SIZE: 80,
frames: 5,
hiding: 0,
jumping: 1,
state: this.hiding,
sourceX: 0,
sourceY: 0,
currentFrame: 0,
COLUMNS: 3,
start: function() {
if (this.currentFrame < this.frames) {
this.sourceX = Math.floor(this.currentFrame % this.COLUMNS) * this.SIZE;
this.sourceY = Math.floor(this.currentFrame/this.COLUMNS) * this.SIZE;
this.currentFrame++;
renderImage();
} else {
window.clearInterval(interval);
this.sourceX = 0;
this.sourceY = 0;
this.currentFrame = 0;
}
}
};
var x = 0;
var y = 0;
function renderMap() {
for (var i = 0; i < map.length; i++) {
for (var j = 0; j < map[0].length; j++) {
switch (map[i][j]) {
case 0:
drawingSurface.drawImage(image,
0, 0, monster.SIZE, monster.SIZE, (j * imgSize) + spaceInc, i * imgSize, imgSize, imgSize);
if (spaceInc >= (map[0].length - 1) * inc) {
// reset increment
spaceInc = 0;
} else {
spaceInc += inc;
}
console.log("Case 0");
break;
case 1:
x = map[i][j] * monster.SIZE
y = map[j] * monster.SIZE;
stGame();
console.log("Case 1");
break;
default:
console.log(j);
break;
}
}
}
}
function stGame() {
interval = window.setInterval(function() {
monster.start();
}, 300);
}
function loadHandler() {
adjustCanvas();
renderMap();
}
function renderImage() {
drawingSurface.drawImage(image,
monster.sourceX, monster.sourceY, monster.SIZE, monster.SIZE,
x, y, monster.SIZE, monster.SIZE);
}
非常感谢! :)真的很感激时间和精力。 – DaBaws