update

11.风扇.html

@@ -126,18 +126,6 @@
                 line(200, 50, 280, 50);
                 line(200, 50, 190, 60);
                 textInfo(`风扇`, "2022-12-17", "赵海洋爸爸", 0);
-
-                // let o = createVector(0, 0);
-                // let v = createVector(100, -100);
-                // let θ = createVector(1, 0).angleBetween(v);
-                // let r = v.mag();
-                // let x = cos(θ) * r;
-                // let y = sin(θ) * r;
-                // translate(width / 2, height / 2);
-                // stroke(255);
-                // strokeWeight(4);
-                // point(0, 0);
-                // point(x, y);
             }
 
             function keyPressed() {

lib/utils.js

@@ -65,3 +65,14 @@ function star(x, y, radius1, radius2, npoints) {
     }
     endShape(CLOSE);
 }
+
+// cartesian to polar
+function cartesianToPolara(x, y) {
+    let v = createVector(x, y);
+    return { r: v.mag(), θ: createVector(1, 0).angleBetween(v) };
+}
+
+// polar to cartesian
+function polarToCartesian(r, θ) {
+    return { x: r * cos(θ), y: r * sin(θ) };
+}