From fa55ed8d956077ad17681091a7fe44236728d0f7 Mon Sep 17 00:00:00 2001
From: wonsunil <seonil6352@gmail.com>
Date: Fri, 14 May 2021 17:34:20 +0900
Subject: [PATCH] Feat: ball bouncing

---
 js/index.js | 126 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 126 insertions(+)
 create mode 100644 js/index.js

diff --git a/js/index.js b/js/index.js
new file mode 100644
index 0000000..3bb4b07
--- /dev/null
+++ b/js/index.js
@@ -0,0 +1,126 @@
+class Ball {
+    constructor(x = 50, y = 50, radius = 15, speed = 5, directX = "right", directY = "down", color = "#333") {
+        this._x = x;
+        this._y = y;
+        this.range = 10;
+        this.radius = radius;
+        this.speed = speed;
+        this._color = color;
+        this._directX = directX;
+        this._directY = directY;
+    };
+
+    get x() { return this._x; };
+    set x(position) { this._x = position; };
+
+    get y() { return this._y; };
+    set y(position) { this._y = position; };
+
+    get color() { return this._color; };
+    set color(hex) { this._color = hex; };
+
+    get directX() { return this._directX; };
+    set directX(direct) { this._directX = direct; };
+
+    get directY() { return this._directY; };
+    set directY(direct) { this._directY = direct; };
+}
+
+const $canvas = document.querySelector("canvas");
+const ctx = $canvas.getContext("2d");
+
+$canvas.width = window.innerWidth - 20;
+$canvas.height = window.innerHeight - 30;
+
+const randomRL = num => num === 1 ? "right" : "left";
+const randomUD = num => num === 1 ? "down" : "up";
+
+const balls = [
+    new Ball(
+        Math.random() * $canvas.width,
+        Math.random() * $canvas.height,
+        50,
+        5,
+        randomRL(Math.floor(Math.random() * 2) + 1),
+        randomUD(Math.floor(Math.random() * 2) + 1),
+        "#427bf5"
+    ),
+    new Ball(
+        Math.random() * $canvas.width,
+        Math.random() * $canvas.height,
+        50,
+        5,
+        randomRL(Math.floor(Math.random() * 2) + 1),
+        randomUD(Math.floor(Math.random() * 2) + 1),
+        "#42f545"
+    ),
+    new Ball(
+        Math.random() * $canvas.width,
+        Math.random() * $canvas.height,
+        50,
+        5,
+        randomRL(Math.floor(Math.random() * 2) + 1),
+        randomUD(Math.floor(Math.random() * 2) + 1),
+        "#dc7223"
+    ),
+    new Ball(
+        Math.random() * $canvas.width,
+        Math.random() * $canvas.height,
+        50,
+        5,
+        randomRL(Math.floor(Math.random() * 2) + 1),
+        randomUD(Math.floor(Math.random() * 2) + 1),
+        "#e5eb34"
+    ),
+    new Ball(
+        Math.random() * $canvas.width,
+        Math.random() * $canvas.height,
+        50,
+        5,
+        randomRL(Math.floor(Math.random() * 2) + 1),
+        randomUD(Math.floor(Math.random() * 2) + 1),
+        "#e042f5"
+    ),
+];
+
+const drawBall = () => {
+    ctx.clearRect(0, 0, $canvas.width, $canvas.height);
+
+    for (let i = 0, limit = balls.length; i < limit; i++) {
+        const ball = balls[i];
+        const { x, y, radius, directX, directY, speed, color } = ball;
+
+        for (let j = 0; j < limit; j++) {
+            if (j !== i) {
+                const ball2 = balls[j];
+                const xRange = x > ball2.x ? x - ball2.x : ball2.x - x;
+                const yRange = y > ball2.y ? y - ball2.y : ball2.y - y;
+                const range = radius + ball2.radius;
+
+                if(Math.sqrt(Math.pow(xRange, 2) + Math.pow(yRange, 2)) < range) {
+                    
+                };
+            };
+        }
+
+        if (directX === "right" && x >= $canvas.width - radius) ball.directX = "left";
+        if (directX === "left" && x <= radius) ball.directX = "right";
+
+        if (directY === "down" && y >= $canvas.height - radius) ball.directY = "up";
+        if (directY === "up" && y <= radius) ball.directY = "down";
+
+        if (directX === "right") ball.x += speed;
+        else if (directX === "left") ball.x -= speed;
+
+        if (directY === "down") ball.y += speed;
+        else if (directY === "up") ball.y -= speed;
+
+        ctx.fillStyle = color;
+        ctx.beginPath();
+        ctx.arc(x, y, radius, 0, 2 * Math.PI);
+        ctx.fill();
+    }
+
+    requestAnimationFrame(drawBall);
+};
+requestAnimationFrame(drawBall);
\ No newline at end of file