(function(global, factory) {
  typeof exports === "object" && typeof module !== "undefined" ? factory(exports) : typeof define === "function" && define.amd ? define(["exports"], factory) : (global = typeof globalThis !== "undefined" ? globalThis : global || self, factory(global.feng3d = {}));
})(this, function(exports2) {
  "use strict";
  function earcut$1(vertices, holes, dimensions) {
    dimensions = dimensions || 2;
    const hasHoles = holes && holes.length;
    const outerLen = hasHoles ? holes[0] * dimensions : vertices.length;
    let outerNode = linkedList(vertices, 0, outerLen, dimensions, true);
    const triangles = [];
    if (!outerNode || outerNode.next === outerNode.prev)
      return triangles;
    let minX;
    let minY;
    let maxX;
    let maxY;
    let x;
    let y;
    let invSize;
    if (hasHoles)
      outerNode = eliminateHoles(vertices, holes, outerNode, dimensions);
    if (vertices.length > 80 * dimensions) {
      minX = maxX = vertices[0];
      minY = maxY = vertices[1];
      for (let i = dimensions; i < outerLen; i += dimensions) {
        x = vertices[i];
        y = vertices[i + 1];
        if (x < minX)
          minX = x;
        if (y < minY)
          minY = y;
        if (x > maxX)
          maxX = x;
        if (y > maxY)
          maxY = y;
      }
      invSize = Math.max(maxX - minX, maxY - minY);
      invSize = invSize !== 0 ? 32767 / invSize : 0;
    }
    earcutLinked(outerNode, triangles, dimensions, minX, minY, invSize, 0);
    return triangles;
  }
  function linkedList(data, start, end, dim, clockwise) {
    let i;
    let last;
    if (clockwise === signedArea(data, start, end, dim) > 0) {
      for (i = start; i < end; i += dim)
        last = insertNode(i, data[i], data[i + 1], last);
    } else {
      for (i = end - dim; i >= start; i -= dim)
        last = insertNode(i, data[i], data[i + 1], last);
    }
    if (last && equals(last, last.next)) {
      removeNode(last);
      last = last.next;
    }
    return last;
  }
  function filterPoints(start, end) {
    if (!start)
      return start;
    if (!end)
      end = start;
    let p = start;
    let again;
    do {
      again = false;
      if (!p.steiner && (equals(p, p.next) || area(p.prev, p, p.next) === 0)) {
        removeNode(p);
        p = end = p.prev;
        if (p === p.next)
          break;
        again = true;
      } else {
        p = p.next;
      }
    } while (again || p !== end);
    return end;
  }
  function earcutLinked(ear, triangles, dim, minX, minY, invSize, pass) {
    if (!ear)
      return;
    if (!pass && invSize)
      indexCurve(ear, minX, minY, invSize);
    let stop = ear;
    let prev;
    let next;
    while (ear.prev !== ear.next) {
      prev = ear.prev;
      next = ear.next;
      if (invSize ? isEarHashed(ear, minX, minY, invSize) : isEar(ear)) {
        triangles.push(prev.i / dim | 0);
        triangles.push(ear.i / dim | 0);
        triangles.push(next.i / dim | 0);
        removeNode(ear);
        ear = next.next;
        stop = next.next;
        continue;
      }
      ear = next;
      if (ear === stop) {
        if (!pass) {
          earcutLinked(filterPoints(ear), triangles, dim, minX, minY, invSize, 1);
        } else if (pass === 1) {
          ear = cureLocalIntersections(filterPoints(ear), triangles, dim);
          earcutLinked(ear, triangles, dim, minX, minY, invSize, 2);
        } else if (pass === 2) {
          splitEarcut(ear, triangles, dim, minX, minY, invSize);
        }
        break;
      }
    }
  }
  function isEar(ear) {
    const a = ear.prev;
    const b = ear;
    const c = ear.next;
    if (area(a, b, c) >= 0)
      return false;
    const ax = a.x;
    const bx = b.x;
    const cx = c.x;
    const ay = a.y;
    const by = b.y;
    const cy = c.y;
    const x0 = ax < bx ? ax < cx ? ax : cx : bx < cx ? bx : cx;
    const y0 = ay < by ? ay < cy ? ay : cy : by < cy ? by : cy;
    const x1 = ax > bx ? ax > cx ? ax : cx : bx > cx ? bx : cx;
    const y1 = ay > by ? ay > cy ? ay : cy : by > cy ? by : cy;
    let p = c.next;
    while (p !== a) {
      if (p.x >= x0 && p.x <= x1 && p.y >= y0 && p.y <= y1 && pointInTriangle(ax, ay, bx, by, cx, cy, p.x, p.y) && area(p.prev, p, p.next) >= 0)
        return false;
      p = p.next;
    }
    return true;
  }
  function isEarHashed(ear, minX, minY, invSize) {
    const a = ear.prev;
    const b = ear;
    const c = ear.next;
    if (area(a, b, c) >= 0)
      return false;
    const ax = a.x;
    const bx = b.x;
    const cx = c.x;
    const ay = a.y;
    const by = b.y;
    const cy = c.y;
    const x0 = ax < bx ? ax < cx ? ax : cx : bx < cx ? bx : cx;
    const y0 = ay < by ? ay < cy ? ay : cy : by < cy ? by : cy;
    const x1 = ax > bx ? ax > cx ? ax : cx : bx > cx ? bx : cx;
    const y1 = ay > by ? ay > cy ? ay : cy : by > cy ? by : cy;
    const minZ = zOrder(x0, y0, minX, minY, invSize);
    const maxZ = zOrder(x1, y1, minX, minY, invSize);
    let p = ear.prevZ;
    let n = ear.nextZ;
    while (p && p.z >= minZ && n && n.z <= maxZ) {
      if (p.x >= x0 && p.x <= x1 && p.y >= y0 && p.y <= y1 && p !== a && p !== c && pointInTriangle(ax, ay, bx, by, cx, cy, p.x, p.y) && area(p.prev, p, p.next) >= 0)
        return false;
      p = p.prevZ;
      if (n.x >= x0 && n.x <= x1 && n.y >= y0 && n.y <= y1 && n !== a && n !== c && pointInTriangle(ax, ay, bx, by, cx, cy, n.x, n.y) && area(n.prev, n, n.next) >= 0)
        return false;
      n = n.nextZ;
    }
    while (p && p.z >= minZ) {
      if (p.x >= x0 && p.x <= x1 && p.y >= y0 && p.y <= y1 && p !== a && p !== c && pointInTriangle(ax, ay, bx, by, cx, cy, p.x, p.y) && area(p.prev, p, p.next) >= 0)
        return false;
      p = p.prevZ;
    }
    while (n && n.z <= maxZ) {
      if (n.x >= x0 && n.x <= x1 && n.y >= y0 && n.y <= y1 && n !== a && n !== c && pointInTriangle(ax, ay, bx, by, cx, cy, n.x, n.y) && area(n.prev, n, n.next) >= 0)
        return false;
      n = n.nextZ;
    }
    return true;
  }
  function cureLocalIntersections(start, triangles, dim) {
    let p = start;
    do {
      const a = p.prev;
      const b = p.next.next;
      if (!equals(a, b) && intersects(a, p, p.next, b) && locallyInside(a, b) && locallyInside(b, a)) {
        triangles.push(a.i / dim | 0);
        triangles.push(p.i / dim | 0);
        triangles.push(b.i / dim | 0);
        removeNode(p);
        removeNode(p.next);
        p = start = b;
      }
      p = p.next;
    } while (p !== start);
    return filterPoints(p);
  }
  function splitEarcut(start, triangles, dim, minX, minY, invSize) {
    let a = start;
    do {
      let b = a.next.next;
      while (b !== a.prev) {
        if (a.i !== b.i && isValidDiagonal(a, b)) {
          let c = splitPolygon(a, b);
          a = filterPoints(a, a.next);
          c = filterPoints(c, c.next);
          earcutLinked(a, triangles, dim, minX, minY, invSize, 0);
          earcutLinked(c, triangles, dim, minX, minY, invSize, 0);
          return;
        }
        b = b.next;
      }
      a = a.next;
    } while (a !== start);
  }
  function eliminateHoles(data, holeIndices, outerNode, dim) {
    const queue = [];
    let i;
    let len;
    let start;
    let end;
    let list;
    for (i = 0, len = holeIndices.length; i < len; i++) {
      start = holeIndices[i] * dim;
      end = i < len - 1 ? holeIndices[i + 1] * dim : data.length;
      list = linkedList(data, start, end, dim, false);
      if (list === list.next)
        list.steiner = true;
      queue.push(getLeftmost(list));
    }
    queue.sort(compareX);
    for (i = 0; i < queue.length; i++) {
      outerNode = eliminateHole(queue[i], outerNode);
    }
    return outerNode;
  }
  function compareX(a, b) {
    return a.x - b.x;
  }
  function eliminateHole(hole, outerNode) {
    const bridge = findHoleBridge(hole, outerNode);
    if (!bridge) {
      return outerNode;
    }
    const bridgeReverse = splitPolygon(bridge, hole);
    filterPoints(bridgeReverse, bridgeReverse.next);
    return filterPoints(bridge, bridge.next);
  }
  function findHoleBridge(hole, outerNode) {
    let p = outerNode;
    const hx = hole.x;
    const hy = hole.y;
    let qx = -Infinity;
    let m;
    do {
      if (hy <= p.y && hy >= p.next.y && p.next.y !== p.y) {
        const x = p.x + (hy - p.y) * (p.next.x - p.x) / (p.next.y - p.y);
        if (x <= hx && x > qx) {
          qx = x;
          m = p.x < p.next.x ? p : p.next;
          if (x === hx)
            return m;
        }
      }
      p = p.next;
    } while (p !== outerNode);
    if (!m)
      return null;
    const stop = m;
    const mx = m.x;
    const my = m.y;
    let tanMin = Infinity;
    let tan;
    p = m;
    do {
      if (hx >= p.x && p.x >= mx && hx !== p.x && pointInTriangle(hy < my ? hx : qx, hy, mx, my, hy < my ? qx : hx, hy, p.x, p.y)) {
        tan = Math.abs(hy - p.y) / (hx - p.x);
        if (locallyInside(p, hole) && (tan < tanMin || tan === tanMin && (p.x > m.x || p.x === m.x && sectorContainsSector(m, p)))) {
          m = p;
          tanMin = tan;
        }
      }
      p = p.next;
    } while (p !== stop);
    return m;
  }
  function sectorContainsSector(m, p) {
    return area(m.prev, m, p.prev) < 0 && area(p.next, m, m.next) < 0;
  }
  function indexCurve(start, minX, minY, invSize) {
    let p = start;
    do {
      if (p.z === 0)
        p.z = zOrder(p.x, p.y, minX, minY, invSize);
      p.prevZ = p.prev;
      p.nextZ = p.next;
      p = p.next;
    } while (p !== start);
    p.prevZ.nextZ = null;
    p.prevZ = null;
    sortLinked(p);
  }
  function sortLinked(list) {
    let i;
    let p;
    let q;
    let e;
    let tail;
    let numMerges;
    let pSize;
    let qSize;
    let inSize = 1;
    do {
      p = list;
      list = null;
      tail = null;
      numMerges = 0;
      while (p) {
        numMerges++;
        q = p;
        pSize = 0;
        for (i = 0; i < inSize; i++) {
          pSize++;
          q = q.nextZ;
          if (!q)
            break;
        }
        qSize = inSize;
        while (pSize > 0 || qSize > 0 && q) {
          if (pSize !== 0 && (qSize === 0 || !q || p.z <= q.z)) {
            e = p;
            p = p.nextZ;
            pSize--;
          } else {
            e = q;
            q = q.nextZ;
            qSize--;
          }
          if (tail)
            tail.nextZ = e;
          else
            list = e;
          e.prevZ = tail;
          tail = e;
        }
        p = q;
      }
      tail.nextZ = null;
      inSize *= 2;
    } while (numMerges > 1);
    return list;
  }
  function zOrder(x, y, minX, minY, invSize) {
    x = (x - minX) * invSize | 0;
    y = (y - minY) * invSize | 0;
    x = (x | x << 8) & 16711935;
    x = (x | x << 4) & 252645135;
    x = (x | x << 2) & 858993459;
    x = (x | x << 1) & 1431655765;
    y = (y | y << 8) & 16711935;
    y = (y | y << 4) & 252645135;
    y = (y | y << 2) & 858993459;
    y = (y | y << 1) & 1431655765;
    return x | y << 1;
  }
  function getLeftmost(start) {
    let p = start;
    let leftmost = start;
    do {
      if (p.x < leftmost.x || p.x === leftmost.x && p.y < leftmost.y)
        leftmost = p;
      p = p.next;
    } while (p !== start);
    return leftmost;
  }
  function pointInTriangle(ax, ay, bx, by, cx, cy, px, py) {
    return (cx - px) * (ay - py) >= (ax - px) * (cy - py) && (ax - px) * (by - py) >= (bx - px) * (ay - py) && (bx - px) * (cy - py) >= (cx - px) * (by - py);
  }
  function isValidDiagonal(a, b) {
    return a.next.i !== b.i && a.prev.i !== b.i && !intersectsPolygon(a, b) && (locallyInside(a, b) && locallyInside(b, a) && middleInside(a, b) && (area(a.prev, a, b.prev) || area(a, b.prev, b)) || equals(a, b) && area(a.prev, a, a.next) > 0 && area(b.prev, b, b.next) > 0);
  }
  function area(p, q, r) {
    return (q.y - p.y) * (r.x - q.x) - (q.x - p.x) * (r.y - q.y);
  }
  function equals(p1, p2) {
    return p1.x === p2.x && p1.y === p2.y;
  }
  function intersects(p1, q1, p2, q2) {
    const o1 = sign(area(p1, q1, p2));
    const o2 = sign(area(p1, q1, q2));
    const o3 = sign(area(p2, q2, p1));
    const o4 = sign(area(p2, q2, q1));
    if (o1 !== o2 && o3 !== o4)
      return true;
    if (o1 === 0 && onSegment(p1, p2, q1))
      return true;
    if (o2 === 0 && onSegment(p1, q2, q1))
      return true;
    if (o3 === 0 && onSegment(p2, p1, q2))
      return true;
    if (o4 === 0 && onSegment(p2, q1, q2))
      return true;
    return false;
  }
  function onSegment(p, q, r) {
    return q.x <= Math.max(p.x, r.x) && q.x >= Math.min(p.x, r.x) && q.y <= Math.max(p.y, r.y) && q.y >= Math.min(p.y, r.y);
  }
  function sign(num) {
    return num > 0 ? 1 : num < 0 ? -1 : 0;
  }
  function intersectsPolygon(a, b) {
    let p = a;
    do {
      if (p.i !== a.i && p.next.i !== a.i && p.i !== b.i && p.next.i !== b.i && intersects(p, p.next, a, b))
        return true;
      p = p.next;
    } while (p !== a);
    return false;
  }
  function locallyInside(a, b) {
    return area(a.prev, a, a.next) < 0 ? area(a, b, a.next) >= 0 && area(a, a.prev, b) >= 0 : area(a, b, a.prev) < 0 || area(a, a.next, b) < 0;
  }
  function middleInside(a, b) {
    let p = a;
    let inside = false;
    const px = (a.x + b.x) / 2;
    const py = (a.y + b.y) / 2;
    do {
      if (p.y > py !== p.next.y > py && p.next.y !== p.y && px < (p.next.x - p.x) * (py - p.y) / (p.next.y - p.y) + p.x) {
        inside = !inside;
      }
      p = p.next;
    } while (p !== a);
    return inside;
  }
  function splitPolygon(a, b) {
    const a2 = new Node(a.i, a.x, a.y);
    const b2 = new Node(b.i, b.x, b.y);
    const an = a.next;
    const bp = b.prev;
    a.next = b;
    b.prev = a;
    a2.next = an;
    an.prev = a2;
    b2.next = a2;
    a2.prev = b2;
    bp.next = b2;
    b2.prev = bp;
    return b2;
  }
  function insertNode(i, x, y, last) {
    const p = new Node(i, x, y);
    if (!last) {
      p.prev = p;
      p.next = p;
    } else {
      p.next = last.next;
      p.prev = last;
      last.next.prev = p;
      last.next = p;
    }
    return p;
  }
  function removeNode(p) {
    p.next.prev = p.prev;
    p.prev.next = p.next;
    if (p.prevZ)
      p.prevZ.nextZ = p.nextZ;
    if (p.nextZ)
      p.nextZ.prevZ = p.prevZ;
  }
  class Node {
    constructor(i, x, y) {
      this.i = i;
      this.x = x;
      this.y = y;
      this.prev = null;
      this.next = null;
      this.z = 0;
      this.prevZ = null;
      this.nextZ = null;
      this.steiner = false;
    }
  }
  function deviation(vertices, holes, dimensions, triangles) {
    const hasHoles = holes && holes.length;
    const outerLen = hasHoles ? holes[0] * dimensions : vertices.length;
    let polygonArea = Math.abs(signedArea(vertices, 0, outerLen, dimensions));
    if (hasHoles) {
      for (let i = 0, len = holes.length; i < len; i++) {
        const start = holes[i] * dimensions;
        const end = i < len - 1 ? holes[i + 1] * dimensions : vertices.length;
        polygonArea -= Math.abs(signedArea(vertices, start, end, dimensions));
      }
    }
    let trianglesArea = 0;
    for (let i = 0; i < triangles.length; i += 3) {
      const a = triangles[i] * dimensions;
      const b = triangles[i + 1] * dimensions;
      const c = triangles[i + 2] * dimensions;
      trianglesArea += Math.abs(
        (vertices[a] - vertices[c]) * (vertices[b + 1] - vertices[a + 1]) - (vertices[a] - vertices[b]) * (vertices[c + 1] - vertices[a + 1])
      );
    }
    return polygonArea === 0 && trianglesArea === 0 ? 0 : Math.abs((trianglesArea - polygonArea) / polygonArea);
  }
  function signedArea(data, start, end, dim) {
    let sum = 0;
    for (let i = start, j = end - dim; i < end; i += dim) {
      sum += (data[j] - data[i]) * (data[i + 1] + data[j + 1]);
      j = i;
    }
    return sum;
  }
  function flatten(data) {
    const dim = data[0][0].length;
    const result = { vertices: [], holes: [], dimensions: dim };
    let holeIndex = 0;
    for (let i = 0; i < data.length; i++) {
      for (let j = 0; j < data[i].length; j++) {
        for (let d = 0; d < dim; d++)
          result.vertices.push(data[i][j][d]);
      }
      if (i > 0) {
        holeIndex += data[i - 1].length;
        result.holes.push(holeIndex);
      }
    }
    return result;
  }
  const earcut = earcut$1;
  earcut.flatten = flatten;
  earcut.deviation = deviation;
  exports2.earcut = earcut;
  Object.defineProperty(exports2, Symbol.toStringTag, { value: "Module" });
});
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