slides/webgl/asset/common/shapefile.js

// https://github.com/mbostock/shapefile Version 0.6.2. Copyright 2017 Mike Bostock.
(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
    typeof define === 'function' && define.amd ? define(['exports'], factory) :
    (factory((global.shapefile = global.shapefile || {})));
}(this, (function (exports) { 'use strict';

var array_cancel = function() {
  this._array = null;
  return Promise.resolve();
};

var array_read = function() {
  var array = this._array;
  this._array = null;
  return Promise.resolve(array ? {done: false, value: array} : {done: true, value: undefined});
};

function array(array) {
  return new ArraySource(array instanceof Uint8Array ? array : new Uint8Array(array));
}

function ArraySource(array) {
  this._array = array;
}

ArraySource.prototype.read = array_read;
ArraySource.prototype.cancel = array_cancel;

var fetchPath = function(url) {
  return fetch(url).then(function(response) {
    return response.body && response.body.getReader
        ? response.body.getReader()
        : response.arrayBuffer().then(array);
  });
};

var requestPath = function(url) {
  return new Promise(function(resolve, reject) {
    var request = new XMLHttpRequest;
    request.responseType = "arraybuffer";
    request.onload = function() { resolve(array(request.response)); };
    request.onerror = reject;
    request.ontimeout = reject;
    request.open("GET", url, true);
    request.send();
  });
};

function path(path) {
  return (typeof fetch === "function" ? fetchPath : requestPath)(path);
}

function stream(source) {
  return typeof source.read === "function" ? source : source.getReader();
}

var empty = new Uint8Array(0);

var slice_cancel = function() {
  return this._source.cancel();
};

function concat(a, b) {
  if (!a.length) return b;
  if (!b.length) return a;
  var c = new Uint8Array(a.length + b.length);
  c.set(a);
  c.set(b, a.length);
  return c;
}

var slice_read = function() {
  var that = this, array = that._array.subarray(that._index);
  return that._source.read().then(function(result) {
    that._array = empty;
    that._index = 0;
    return result.done ? (array.length > 0
        ? {done: false, value: array}
        : {done: true, value: undefined})
        : {done: false, value: concat(array, result.value)};
  });
};

var slice_slice = function(length) {
  if ((length |= 0) < 0) throw new Error("invalid length");
  var that = this, index = this._array.length - this._index;

  // If the request fits within the remaining buffer, resolve it immediately.
  if (this._index + length <= this._array.length) {
    return Promise.resolve(this._array.subarray(this._index, this._index += length));
  }

  // Otherwise, read chunks repeatedly until the request is fulfilled.
  var array = new Uint8Array(length);
  array.set(this._array.subarray(this._index));
  return (function read() {
    return that._source.read().then(function(result) {

      // When done, it鈥檚 possible the request wasn鈥檛 fully fullfilled!
      // If so, the pre-allocated array is too big and needs slicing.
      if (result.done) {
        that._array = empty;
        that._index = 0;
        return index > 0 ? array.subarray(0, index) : null;
      }

      // If this chunk fulfills the request, return the resulting array.
      if (index + result.value.length >= length) {
        that._array = result.value;
        that._index = length - index;
        array.set(result.value.subarray(0, length - index), index);
        return array;
      }

      // Otherwise copy this chunk into the array, then read the next chunk.
      array.set(result.value, index);
      index += result.value.length;
      return read();
    });
  })();
};

function slice(source) {
  return typeof source.slice === "function" ? source :
      new SliceSource(typeof source.read === "function" ? source
          : source.getReader());
}

function SliceSource(source) {
  this._source = source;
  this._array = empty;
  this._index = 0;
}

SliceSource.prototype.read = slice_read;
SliceSource.prototype.slice = slice_slice;
SliceSource.prototype.cancel = slice_cancel;

var dbf_cancel = function() {
  return this._source.cancel();
};

var readBoolean = function(value) {
  return /^[nf]$/i.test(value) ? false
      : /^[yt]$/i.test(value) ? true
      : null;
};

var readDate = function(value) {
  return new Date(+value.substring(0, 4), value.substring(4, 6) - 1, +value.substring(6, 8));
};

var readNumber = function(value) {
  return !(value = value.trim()) || isNaN(value = +value) ? null : value;
};

var readString = function(value) {
  return value.trim() || null;
};

var types = {
  B: readNumber,
  C: readString,
  D: readDate,
  F: readNumber,
  L: readBoolean,
  M: readNumber,
  N: readNumber
};

var dbf_read = function() {
  var that = this, i = 1;
  return that._source.slice(that._recordLength).then(function(value) {
    return value && (value[0] !== 0x1a) ? {done: false, value: that._fields.reduce(function(p, f) {
      p[f.name] = types[f.type](that._decode(value.subarray(i, i += f.length)));
      return p;
    }, {})} : {done: true, value: undefined};
  });
};

var view = function(array) {
  return new DataView(array.buffer, array.byteOffset, array.byteLength);
};

var dbf = function(source, decoder) {
  source = slice(source);
  return source.slice(32).then(function(array) {
    var head = view(array);
    return source.slice(head.getUint16(8, true) - 32).then(function(array) {
      return new Dbf(source, decoder, head, view(array));
    });
  });
};

function Dbf(source, decoder, head, body) {
  this._source = source;
  this._decode = decoder.decode.bind(decoder);
  this._recordLength = head.getUint16(10, true);
  this._fields = [];
  for (var n = 0; body.getUint8(n) !== 0x0d; n += 32) {
    for (var j = 0; j < 11; ++j) if (body.getUint8(n + j) === 0) break;
    this._fields.push({
      name: this._decode(new Uint8Array(body.buffer, body.byteOffset + n, j)),
      type: String.fromCharCode(body.getUint8(n + 11)),
      length: body.getUint8(n + 16)
    });
  }
}

var prototype = Dbf.prototype;
prototype.read = dbf_read;
prototype.cancel = dbf_cancel;

function cancel() {
  return this._source.cancel();
}

var readMultiPoint = function(record) {
  var i = 40, j, n = record.getInt32(36, true), coordinates = new Array(n);
  for (j = 0; j < n; ++j, i += 16) coordinates[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];
  return {type: "MultiPoint", coordinates: coordinates};
};

var readNull = function() {
  return null;
};

var readPoint = function(record) {
  return {type: "Point", coordinates: [record.getFloat64(4, true), record.getFloat64(12, true)]};
};

var readPolygon = function(record) {
  var i = 44, j, n = record.getInt32(36, true), m = record.getInt32(40, true), parts = new Array(n), points = new Array(m), polygons = [], holes = [];
  for (j = 0; j < n; ++j, i += 4) parts[j] = record.getInt32(i, true);
  for (j = 0; j < m; ++j, i += 16) points[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];

  parts.forEach(function(i, j) {
    var ring = points.slice(i, parts[j + 1]);
    if (ringClockwise(ring)) polygons.push([ring]);
    else holes.push(ring);
  });

  holes.forEach(function(hole) {
    polygons.some(function(polygon) {
      if (ringContainsSome(polygon[0], hole)) {
        polygon.push(hole);
        return true;
      }
    }) || polygons.push([hole]);
  });

  return polygons.length === 1
      ? {type: "Polygon", coordinates: polygons[0]}
      : {type: "MultiPolygon", coordinates: polygons};
};

function ringClockwise(ring) {
  if ((n = ring.length) < 4) return false;
  var i = 0, n, area = ring[n - 1][1] * ring[0][0] - ring[n - 1][0] * ring[0][1];
  while (++i < n) area += ring[i - 1][1] * ring[i][0] - ring[i - 1][0] * ring[i][1];
  return area >= 0;
}

function ringContainsSome(ring, hole) {
  var i = -1, n = hole.length, c;
  while (++i < n) {
    if (c = ringContains(ring, hole[i])) {
      return c > 0;
    }
  }
  return false;
}

function ringContains(ring, point) {
  var x = point[0], y = point[1], contains = -1;
  for (var i = 0, n = ring.length, j = n - 1; i < n; j = i++) {
    var pi = ring[i], xi = pi[0], yi = pi[1],
        pj = ring[j], xj = pj[0], yj = pj[1];
    if (segmentContains(pi, pj, point)) {
      return 0;
    }
    if (((yi > y) !== (yj > y)) && ((x < (xj - xi) * (y - yi) / (yj - yi) + xi))) {
      contains = -contains;
    }
  }
  return contains;
}

function segmentContains(p0, p1, p2) {
  var x20 = p2[0] - p0[0], y20 = p2[1] - p0[1];
  if (x20 === 0 && y20 === 0) return true;
  var x10 = p1[0] - p0[0], y10 = p1[1] - p0[1];
  if (x10 === 0 && y10 === 0) return false;
  var t = (x20 * x10 + y20 * y10) / (x10 * x10 + y10 * y10);
  return t < 0 || t > 1 ? false : t === 0 || t === 1 ? true : t * x10 === x20 && t * y10 === y20;
}

var readPolyLine = function(record) {
  var i = 44, j, n = record.getInt32(36, true), m = record.getInt32(40, true), parts = new Array(n), points = new Array(m);
  for (j = 0; j < n; ++j, i += 4) parts[j] = record.getInt32(i, true);
  for (j = 0; j < m; ++j, i += 16) points[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];
  return n === 1
      ? {type: "LineString", coordinates: points}
      : {type: "MultiLineString", coordinates: parts.map(function(i, j) { return points.slice(i, parts[j + 1]); })};
};

var shp_read = function() {
  var that = this;
  return that._source.slice(8).then(function(array) {
    if (array == null) return {done: true, value: undefined};
    var header = view(array);
    return that._source.slice(header.getInt32(4, false) * 2).then(function(array) {
      var record = view(array);
      return {done: false, value: record.getInt32(0, true) ? that._type(record) : readNull()};
    });
  });
};

var types$1 = {
  0: readNull,
  1: readPoint,
  3: readPolyLine,
  5: readPolygon,
  8: readMultiPoint,
  11: readPoint,
  13: readPolyLine,
  15: readPolygon,
  18: readMultiPoint
};

var shp = function(source) {
  source = slice(source);
  return source.slice(100).then(function(array) {
    return new Shp(source, view(array));
  });
};

function Shp(source, header) {
  var type = header.getInt32(32, true);
  if (!(type in types$1)) throw new Error("unsupported shape type: " + type);
  this._source = source;
  this._type = types$1[type];
  this.bbox = [header.getFloat64(36, true), header.getFloat64(44, true), header.getFloat64(52, true), header.getFloat64(60, true)];
}

var prototype$2 = Shp.prototype;
prototype$2.read = shp_read;
prototype$2.cancel = cancel;

function noop() {}

var shapefile_cancel = function() {
  return Promise.all([
    this._dbf && this._dbf.cancel(),
    this._shp.cancel()
  ]).then(noop);
};

var shapefile_read = function() {
  var that = this;
  return Promise.all([
    that._dbf ? that._dbf.read() : {value: {}},
    that._shp.read()
  ]).then(function(results) {
    var dbf = results[0], shp = results[1];
    return shp.done ? shp : {
      done: false,
      value: {
        type: "Feature",
        properties: dbf.value,
        geometry: shp.value
      }
    };
  });
};

var shapefile = function(shpSource, dbfSource, decoder) {
  return Promise.all([
    shp(shpSource),
    dbfSource && dbf(dbfSource, decoder)
  ]).then(function(sources) {
    return new Shapefile(sources[0], sources[1]);
  });
};

function Shapefile(shp$$1, dbf$$1) {
  this._shp = shp$$1;
  this._dbf = dbf$$1;
  this.bbox = shp$$1.bbox;
}

var prototype$1 = Shapefile.prototype;
prototype$1.read = shapefile_read;
prototype$1.cancel = shapefile_cancel;

function open(shp$$1, dbf$$1, options) {
  if (typeof dbf$$1 === "string") {
    if (!/\.dbf$/.test(dbf$$1)) dbf$$1 += ".dbf";
    dbf$$1 = path(dbf$$1, options);
  } else if (dbf$$1 instanceof ArrayBuffer || dbf$$1 instanceof Uint8Array) {
    dbf$$1 = array(dbf$$1);
  } else if (dbf$$1 != null) {
    dbf$$1 = stream(dbf$$1);
  }
  if (typeof shp$$1 === "string") {
    if (!/\.shp$/.test(shp$$1)) shp$$1 += ".shp";
    if (dbf$$1 === undefined) dbf$$1 = path(shp$$1.substring(0, shp$$1.length - 4) + ".dbf", options).catch(function() {});
    shp$$1 = path(shp$$1, options);
  } else if (shp$$1 instanceof ArrayBuffer || shp$$1 instanceof Uint8Array) {
    shp$$1 = array(shp$$1);
  } else {
    shp$$1 = stream(shp$$1);
  }
  return Promise.all([shp$$1, dbf$$1]).then(function(sources) {
    var shp$$1 = sources[0], dbf$$1 = sources[1], encoding = "windows-1252";
    if (options && options.encoding != null) encoding = options.encoding;
    return shapefile(shp$$1, dbf$$1, dbf$$1 && new TextDecoder(encoding));
  });
}

function openShp(source, options) {
  if (typeof source === "string") {
    if (!/\.shp$/.test(source)) source += ".shp";
    source = path(source, options);
  } else if (source instanceof ArrayBuffer || source instanceof Uint8Array) {
    source = array(source);
  } else {
    source = stream(source);
  }
  return Promise.resolve(source).then(shp);
}

function openDbf(source, options) {
  var encoding = "windows-1252";
  if (options && options.encoding != null) encoding = options.encoding;
  encoding = new TextDecoder(encoding);
  if (typeof source === "string") {
    if (!/\.dbf$/.test(source)) source += ".dbf";
    source = path(source, options);
  } else if (source instanceof ArrayBuffer || source instanceof Uint8Array) {
    source = array(source);
  } else {
    source = stream(source);
  }
  return Promise.resolve(source).then(function(source) {
    return dbf(source, encoding);
  });
}

function read(shp$$1, dbf$$1, options) {
  return open(shp$$1, dbf$$1, options).then(function(source) {
    var features = [], collection = {type: "FeatureCollection", features: features, bbox: source.bbox};
    return source.read().then(function read(result) {
      if (result.done) return collection;
      features.push(result.value);
      return source.read().then(read);
    });
  });
}

exports.open = open;
exports.openShp = openShp;
exports.openDbf = openDbf;
exports.read = read;

Object.defineProperty(exports, '__esModule', { value: true });

})));