update

2022-12-30 18:39:58 +08:00 · 2022-12-30 18:39:58 +08:00 · 666a097850
commit 666a097850
parent 348c4fa06a
2 changed files with 68 additions and 0 deletions
--- a/13.画圆.html
+++ b/13.画圆.html
@ -0,0 +1,50 @@
+<!DOCTYPE html>
+<html lang="zh">
+    <head>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+        <link rel="stylesheet" href="/css/style.css" />
+        <title>画圆</title>
+        <script src="/p5/p5.min.js"></script>
+        <script src="/p5/addons/p5.sound.min.js"></script>
+        <script src="/lib/utils.js"></script>
+        <script>
+            let o, d;
+            let circles = [];
+
+            function setup() {
+                createCanvas(600, 600);
+                background("#33DDFF");
+                drawGrid(0);
+                noFill();
+                noLoop();
+            }
+
+            function mousePressed() {
+                o = createVector(mouseX, mouseY);
+            }
+
+            function mouseDragged() {
+                let p = createVector(mouseX, mouseY);
+                d = p.sub(o).mag() * 2;
+
+                background("#33DDFF");
+                drawGrid(0);
+                circles.forEach((c) => {
+                    circle(c.x, c.y, c.d);
+                });
+                circle(o.x, o.y, d);
+            }
+
+            function mouseReleased() {
+                let c = { x: o.x, y: o.y, d };
+                circles.push(c);
+            }
+        </script>
+    </head>
+
+    <body>
+        <main></main>
+    </body>
+</html>
--- a/lib/utils.js
+++ b/lib/utils.js
@ -101,3 +101,21 @@ function drawRect(x, y, w, h, c = "bottom") {
    }
    pop();
 }
+
+function luoxuanxian(x, y) {
+    push();
+    noFill();
+    stroke("#FFDD33");
+    strokeWeight(4);
+    translate(x, y);
+    beginShape();
+    for (let θ = 0; θ < PI * 6; θ += 0.1) {
+        let a = 0;
+        let b = 2;
+        let r = a + b * θ;
+        let v = polarToCartesian(r, θ);
+        vertex(v.x, v.y);
+    }
+    endShape();
+    pop();
+}