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HTML

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <p>
  <a href="#" class="link-download">Download displayed SVG</a>
</p>

<svg id="svgField" width="1600" height="3500" viewBox="0 0 1600 3500" xmlns="http://www.w3.org/2000/svg">
</svg>
!

CSS 

              
                svg {
  border: solid thin gray;
}
!

JS 

              
                const SVG = document.getElementById("svgField");
const L = 100;

const R = 0.6; // 0.7; // 1;
const M = 100;

const N = 8; //6; // 8
const θ = (Math.PI * 2) / N;

const CURVE_MARGINE = 0.1;
const WING_MARGINE = 0.1 * 1 / 2;

class Vector2D {
  constructor(x, y) {
    this.x = x;
    this.y = y;
  }

  lift(surface) {
    return new Vector(this.x, this.y, surface(this.x, this.y));
  }

  toArray() {
    return [this.x, this.y];
  }

  m(t) {
    return new Vector2D(this.x * t, this.y * t);
  }

  plus(a) {
    return new Vector2D(this.x + a.x, this.y + a.y);
  }

  minus(a) {
    return this.plus(a.m(-1));
  }

  orthogonal() {
    return new Vector2D(this.y, -this.x); // turn right 90 degree
  }

  ratio(p, a) {
    return this.plus(a.minus(this).m(p));
  }

  innerProduct(v) {
    return this.x * v.x + this.y * v.y;
  }

  norm() {
    return Math.sqrt(this.innerProduct(this));
  }

  normalize() {
    return this.m(1 / this.norm());
  }

  center(v) {
    return this.ratio(1 / 2, v);
  }

  rotate(theta) {
    return new Vector2D(
      this.x * Math.cos(theta) - this.y * Math.sin(theta),
      this.x * Math.sin(theta) + this.y * Math.cos(theta)
    );
  }
}

class Vector3D {
  constructor(x, y, z) {
    this.x = x;
    this.y = y;
    this.z = z;
  }

  toArray() {
    return [this.x, this.y, this.z];
  }

  m(t) {
    return new Vector3D(this.x * t, this.y * t, this.z * t);
  }

  plus(a) {
    return new Vector3D(this.x + a.x, this.y + a.y, this.z + a.z);
  }

  minus(a) {
    return this.plus(a.m(-1));
  }

  ratio(p, a) {
    return this.plus(a.minus(this).m(p));
  }

  innerProduct(v) {
    return this.x * v.x + this.y * v.y + this.z * v.z;
  }

  norm() {
    return Math.sqrt(this.innerProduct(this));
  }

  normalize() {
    return this.m(1 / this.norm());
  }

  center(v) {
    return this.ratio(1 / 2, v);
  }
}

function drawSVGPath(lines, offset, color) {
  let path = document.createElementNS("http://www.w3.org/2000/svg", "path");
  let d = "";
  lines.forEach((line) => {
    let p0 = line[0];
    d += "M " + p0.plus(offset).x * L + " " + p0.plus(offset).y * L;
    line.slice(1).forEach((p) => {
      d += "L " + p.plus(offset).x * L + " " + p.plus(offset).y * L;
    });
  });
  path.setAttribute("d", d);
  path.setAttribute("stroke", color);
  path.setAttribute("fill", "none");
  SVG.appendChild(path);
}

function drawSVGPathEach(lines, offset, color) {
  lines.forEach((line) => {
    let path = document.createElementNS("http://www.w3.org/2000/svg", "path");
    let d = "";
    let p0 = line[0];
    d += "M " + p0.plus(offset).x * L + " " + p0.plus(offset).y * L;
    line.slice(1).forEach((p) => {
      d += "L " + p.plus(offset).x * L + " " + p.plus(offset).y * L;
    });
    path.setAttribute("d", d);
    path.setAttribute("stroke", color);
    path.setAttribute("fill", "none");
    SVG.appendChild(path);
  });
}

// function calcPoint1(z) {
//   let x = Math.sqrt(1 - (z / R) ** 2) / ((Math.sqrt(2) - 1) ** 2 + 1);
//   let y = (Math.sqrt(2) - 1) * x;
//   return new Vector3D(x, y, z);
// }

function calcPoint1(z) {
  // x^2 + y^2 + (z/R)^2 = 1
  // y = 0
  let x = Math.sqrt(1 - (z / R) ** 2);
  let y = 0;
  return new Vector3D(x, y, z);
}

function calcPoint2(z) {
  // x^2 + y^2 + (z/R)^2 = 1
  // y = tan(θ) * x
  let x = Math.sqrt(1 - (z / R) ** 2) / (Math.tan(θ) ** 2 + 1);
  let y = Math.tan(θ) * x;
  return new Vector3D(x, y, z);
}

function createCurveBase() {
  let path = [];
  let pm_last;
  let t = 0;
  for (var i = 0; i <= M; i++) {
    let j = i / M;
    let z = j * R;
    let p1 = calcPoint1(z);
    let p2 = calcPoint2(z);
    let pm = p1.ratio(1 / 2, p2);
    let l = p1.minus(p2).norm() / 2;
    if (pm_last) {
      t += pm.minus(pm_last).norm();
    }
    path.push(new Vector2D(l, t));
    pm_last = pm;
  }

  return path;
}

function createCurve() {
  let path = createCurveBase();

  let w = Math.max(...path.map((p) => p.x));
  let h = Math.max(...path.map((p) => p.y));

  let l = path.length;
  let p_1 = path[l - 1];
  let p_2 = path[l - 2];
  let p_margine = p_1.plus(p_1.minus(p_2).normalize().m(CURVE_MARGINE));
  path.push(p_margine);

  let reversed = path.toReversed().map((p) => new Vector2D(p.x, -p.y));
  reversed.pop();
  path = reversed.concat(path);

  let w2 =
    Math.max(...path.map((p) => p.x)) - Math.min(...path.map((p) => p.x));
  let h2 = Math.max(...path.map((p) => p.y));

  return [path, w, h, w2, h2];
}

function movePath(path, a) {
  return path.map((p) => p.plus(a));
}

function drawFace(lines, w, h, w2, h2) {}

function drawJoints(lines, w, h, w2, h2) {
  //       p0       s0
  //       |        |
  //       p1       s1
  //      /|        |\
  // p3 /  |      s2|__\ s3
  //   |  _|m       |   |
  //   |   |        |___|
  // q3 \  |      t2|  / t3
  //      \|        |/
  //       q1       t1
  //       |        |
  //       q0       t0

  let a = new Vector2D(w, 0);
  let d = w * 2 + WING_MARGINE;

  // 左側
  let p0 = new Vector2D(0, -h2);
  let q0 = new Vector2D(0, h2);
  let m0 = p0.ratio(1 / 2, q0);
  let m1 = m0.minus(a.m(1 / 2));

  let p1 = p0.ratio(1 / 8, q0);
  let p2 = p0.ratio(1 / 4, q0);
  let p3 = p2.minus(a);

  let q1 = q0.ratio(1 / 8, p0);
  let q2 = q0.ratio(1 / 4, p0);
  let q3 = q2.minus(a);

  lines.cut.push([p0, p1, p3], [q3, q1, q0], [p2, q2], [m0, m1]);
  lines.dot.push([p1, p2], [q1, q2]);
  lines.dotcut.push([p3, q3]);

  // 右側
  let dn = new Vector2D(d * N, 0);
  let s0 = p0.plus(dn);
  let t0 = q0.plus(dn);

  let s1 = s0.ratio(1 / 8, t0);
  let s2 = s0.ratio(1 / 4, t0);
  let s3 = s2.plus(a);

  let t1 = t0.ratio(1 / 8, s0);
  let t2 = t0.ratio(1 / 4, s0);
  let t3 = t2.plus(a);

  lines.cut.push([s0, s2], [t0, t2], [s1, s3], [t3, t1]);
  lines.dot.push([s3, s2, t2, t3]);
  lines.dotcut.push([s3, t3]);
}

function drawJoints2(lines, w, h, w2, h2) {
  /*
     p0           s00 s1
     |            :   |
     |            :   |s1
     |            :   |\
     |   p1       : s2|..\ s3
     |   |        :       |
    m| m0|_m1     :       |
     |   |        :       |
     |   |        :    ...|
     |   q1       : t2|  / t3
     |            :   |/
     |            :   |t1
     |            :   |
     q0           t00 t1
  */

  let a = new Vector2D(w / 3, 0);
  let d = w * 2 + WING_MARGINE;

  // 左側
  let p0 = new Vector2D(0, -h2);
  let q0 = new Vector2D(0, h2);
  let m0 = p0.ratio(1 / 2, q0).plus(a.m(2));
  let m1 = m0.plus(a);

  let p1 = p0.ratio(1 / 4, q0).plus(a.m(2));
  let q1 = q0.ratio(1 / 4, p0).plus(a.m(2));

  lines.cut.push([p1, q1], [m0, m1]);
  lines.dotcut.push([p0, q0]);

  // 右側
  let dn = new Vector2D(d * N, 0);
  let s00 = p0.plus(dn);
  let t00 = q0.plus(dn);

  let s0 = s00.plus(a.m(2));
  let t0 = t00.plus(a.m(2));

  let s1 = s0.ratio(1 / 8, t0);
  let s2 = s0.ratio(1 / 4, t0);
  let s3 = s2.plus(a.m(2));

  let t1 = t0.ratio(1 / 8, s0);
  let t2 = t0.ratio(1 / 4, s0);
  let t3 = t2.plus(a.m(2));

  lines.cut.push([s00, s0], [t00, t0], [s0, s2], [t0, t2], [s1, s3], [t3, t1]);
  lines.dot.push([s00, t00], [s3, s2], [t2, t3]);
  lines.dotcut.push([s3, t3]);
}

function drawNWings(lines) {
  let [path, w, h, w2, h2] = createCurve();

  let d = w * 2 + WING_MARGINE;

  for (let i = 0; i < N; i++) {
    let vPath = [new Vector2D(i * d, -h2), new Vector2D(i * d, h2)];
    if (i == 0) {
      //lines.dotcut.push(vPath);
    } else {
      lines.dot.push(vPath);
    }

    let path2 = movePath(path, new Vector2D(w + i * d, 0));
    lines.dot.push(path2);
  }

  let vPath = [new Vector2D(N * d, -h2), new Vector2D(N * d, h2)];
  //lines.cut.push(vPath);

  let hPath0 = [new Vector2D(0, -h2), new Vector2D(N * d, -h2)];
  lines.cut.push(hPath0);

  let hPath1 = [
    new Vector2D(0, h2),
    new Vector2D(N * d, h2)
    //new Vector2D(N * d + (w * 2 - w2), h2)
  ];
  lines.cut.push(hPath1);

  drawFace(lines, w, h, w2, h2);
  //drawJoints(lines, w, h, w2, h2);
  drawJoints2(lines, w, h, w2, h2);
}

function draw(offset) {
  const lines = {
    dot: [],
    cut: [],
    dotcut: []
  };

  drawNWings(lines);

  drawSVGPath(lines.dot, offset, "red");
  drawSVGPath(lines.cut, offset, "blue");
  drawSVGPath(lines.dotcut, offset, "green");
}

draw(new Vector2D(1, 2));

document.querySelector(".link-download").addEventListener("click", (evt) => {
  const svgContent = document.getElementById("svgField").outerHTML,
    blob = new Blob([svgContent], {
      type: "image/svg+xml"
    }),
    url = window.URL.createObjectURL(blob),
    link = evt.target;

  link.target = "_blank";
  link.download = "n_wings.svg";
  link.href = url;
});
!
999px

Console