javascript - 如何使用二维数组将形状绘制到画布上
问题描述
我正在制作一个游戏,我需要从二维数组渲染到画布上我有这个
var map = [
[1,0,1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0],
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0]
]
function drawmap(){
for(y = 0;y < map.length;y++){
for(x = 0;x < map[0].length;x++){
switch(map[y][x]){
case 0:
ctx.fillStyle = "black";
break;
case 1:
ctx.fillStyle = "white";
break;
}
ctx.fillRect(x,y,x + tilesize * 16,y + tilesize * 8)
}
}
}
但它出来的时候又小又扭曲,我认为他们的数学有问题,但我能弄明白。这是一张图片 运行时的 HTML 文件
解决方案
是的,你的数学不正确......
它应该是:
ctx.fillRect(x * tilesize, y * tilesize, tilesize, tilesize)
假设你有方形瓷砖
这是一个正在运行的示例
<canvas id="c" width=800 height=800></canvas>
<script>
const canvas = document.getElementById('c');
const ctx = canvas.getContext('2d');
var tilesize = 10
var map = [
[1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
[0, 0, 0, 2, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 3, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0]
]
function drawmap() {
for (y = 0; y < map.length; y++) {
for (x = 0; x < map[0].length; x++) {
ctx.fillStyle = ["red", "blue", "cyan", "yellow"][map[y][x]]
ctx.fillRect(x * tilesize, y * tilesize, tilesize, tilesize)
}
}
}
drawmap()
</script>
我还使用颜色数组来设置填充样式:
ctx.fillStyle = ["red", "blue", "cyan", "yellow"][map[y][x]]
推荐阅读
- python - Pandas:根据条件删除并计算连续重复项
- java - Android Gradle 项目对 AAR 库的依赖在 3.5.x 版本中失败
- python - 将邮递员片段转换为 python JSON
- kubernetes - “cpu”和“requests.cpu”之间的区别
- liquibase - 为什么 liquibase 试图重新创建表 DATABASECHANGELOG
- azure - Azure webapp:堆栈设置
- php - 在带有工作区的 Laradock 中的 Laravel 5.8 中每分钟运行计划任务时出错
- generic-collections - 如何在给出一个泛型参数时指定它应该实现一些特定的创建方法?
- android - 进度条或搜索栏,就像三星健康
- sql - sql server中的每月总和+ PIVOT