initial commit, worm thingy

sketch.js

@@ -0,0 +1,80 @@
+var vec = p5.Vector;
+
+class Segment {
+  constructor(x, y, size) {
+    this.size = size;
+    this.pos = new vec(x, y);
+    this.forward = new vec(0, 0);
+  }
+
+  get_rel(angle, d) {
+    let dir = vec.rotate(this.forward, angle);
+    dir.setMag(d);
+    return vec.add(this.pos, dir)
+  }
+  
+  follow(x, y) {
+    let target = new vec(x, y);
+    let dir = vec.sub(this.pos, target);
+    this.forward = vec.sub(target, this.pos);
+    dir.setMag(this.size);
+    this.pos = vec.add(target, dir);
+  }
+}
+
+var n = 0;
+var sizes = [10, 15, 20, 25, 30, 24, 27, 21, 15, 17, ]
+var segments = [];
+function setup() {
+  createCanvas(800, 800);
+  n = sizes.length;
+  for (let i = 0; i < n; i++) {
+    let seg = new Segment(400, 400, sizes[i]);
+    segments.push(seg);
+  }
+  
+}
+
+function draw() {
+background(150);
+  
+  // fisica
+  segments[0].follow(mouseX, mouseY);
+  for (let i = 1; i < n; i++) {
+    let prev_seg = segments[i - 1];
+    segments[i].follow(prev_seg.pos.x, prev_seg.pos.y);
+  }
+
+  // dibujar
+  fill(100, 200, 150);
+  stroke(0);
+  strokeWeight(2);
+  
+  beginShape();
+
+  let head = segments[0];
+  let tail = segments[n - 1];
+
+  for (let a = -HALF_PI; a <= HALF_PI; a += PI / 10) {
+    let p = head.get_rel(a, head.size);
+    vertex(p.x, p.y);
+  }
+
+  for (let i = 1; i < n - 1; i++) {
+    let p = segments[i].get_rel(HALF_PI, segments[i].size);
+    vertex(p.x, p.y);
+  }
+
+  for (let a = HALF_PI; a <= HALF_PI + PI; a += PI / 10) {
+    let p = tail.get_rel(a, tail.size);
+    vertex(p.x, p.y);
+  }
+
+  for (let i = n - 2; i >= 1; i--) {
+    let p = segments[i].get_rel(-HALF_PI, segments[i].size);
+    vertex(p.x, p.y);
+  }
+
+
+  endShape(CLOSE);
+}