入门使用：

添加依赖

npm i logic-canvas

在src/index.js下：绘制一个指定原点的坐标系

//引入依赖，注意相对路径
import MyCanvas from "../node_modules/logic-canvas/src/lib/MyCanvas";
let canvas = new MyCanvas(1200, 600, "canvas");//创建一个id为canvas，宽1200px,高600px的画布
canvas.clearWin();//清屏填充
var COO = {x: 360, y: 400};//坐标原点
canvas.drawCoord(COO);//绘制坐标系

绘制n角星

//绘制一个角个数为6，外接圆半径100，内接圆半径55，位置相对于左上角{x: 360, y: 400}处
//描边颜色"#D9ABF8",填充颜色"#F0F674"的多角形
canvas.drawNStar({
    num: 6, R: 100, r: 55, p: COO,
    ss: "#D9ABF8", fs: "#F0F674"
});

绘制长方形

//绘制一个宽100，高50，圆角半径10，位置相对于左上角（200,200）处
//描边颜色"#D9ABF8",不填充,线宽5px的长方形
canvas.drawRect({
    w: 100, h: 50, ra: 10, p: {x: 200, y: 200},
    ss: "#D9ABF8", fs: false, b: 5
});

绘制直线

//绘制给定起点,长度，角度的直线（长度和角度30ms加1）,起点为坐标原点
var count = 0;
canvas.runGo(function (timer) {
    canvas.drawLine({
        p0: {x: 0, y: 0},
        c: count,
        ang: count / 180 * Math.PI,
        ss: canvas.getRandomColor(),//获取随机色
        coo: COO,//设置坐标系
    });
    count++;
    if (count >= 360 + 90) {
        clearInterval(timer);
    }
}, 30);

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使用点集绘制曲线（例：极坐标下，绘制笛卡尔心形曲线）

for (let i = 0; i < 2000; i += 0.1) {
    canvas.drawPointPolar({
        R: 0.5,//点半径
        c: (1 - Math.sin(i / 180 * Math.PI)) * 100,//极坐标下长度
        ang: i / 180 * Math.PI,//极坐标下角度
        coo: COO,
        fs: "#f00"
    });
}

---

根据三点绘制三角形：canvas.drawTrg

var count = 0;
canvas.runGo(function (timer) {
    canvas.clearWin();
    canvas.drawCoord(COO);
    let drawTrg = canvas.drawTrg({
        p0: {x: 0, y: 0},
        p1: {x: count, y: 100},
        p2: {x: 200, y: count/2},
        ss:false,
        coo: COO
    });
    count++;
    if (count >= 360 + 90) {
        clearInterval(timer);
    }
}, 10);

n角星的角数不断增大时：

var count = 0;
canvas.runGo(function (timer) {
    canvas.clearWin();
    canvas.drawCoord(COO);
    canvas.drawNStar({
        num: count, R: 100, r: 55,p:{x:100,y:0},
        ss: false, fs: "#F0F674"
    });
    count++;
    if (count >= 200) {
        clearInterval(timer);
    }
}, 30);