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@deck.gl/experimental-layers

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Experimental layers for deck.gl

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.getTileIndices = getTileIndices; var _viewportMercatorProject = require("viewport-mercator-project"); function _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _nonIterableRest(); } function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance"); } function _iterableToArrayLimit(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; } function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; } function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; var ownKeys = Object.keys(source); if (typeof Object.getOwnPropertySymbols === 'function') { ownKeys = ownKeys.concat(Object.getOwnPropertySymbols(source).filter(function (sym) { return Object.getOwnPropertyDescriptor(source, sym).enumerable; })); } ownKeys.forEach(function (key) { _defineProperty(target, key, source[key]); }); } return target; } function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; } var TILE_SIZE = 512; function getBoundingBox(viewport) { var corners = [viewport.unproject([0, 0]), viewport.unproject([viewport.width, 0]), viewport.unproject([0, viewport.height]), viewport.unproject([viewport.width, viewport.height])]; return [corners.reduce(function (minLng, p) { return minLng < p[0] ? minLng : p[0]; }, 180), corners.reduce(function (minLat, p) { return minLat < p[1] ? minLat : p[1]; }, 90), corners.reduce(function (maxLng, p) { return maxLng > p[0] ? maxLng : p[0]; }, -180), corners.reduce(function (maxLat, p) { return maxLat > p[1] ? maxLat : p[1]; }, -90)]; } function pixelsToTileIndex(a) { return Math.floor(a / TILE_SIZE); } /** * Returns all tile indices in the current viewport. If the current zoom level is smaller * than minZoom, return an empty array. If the current zoom level is greater than maxZoom, * return tiles that are on maxZoom. */ function getTileIndices(viewport, maxZoom, minZoom) { var z = Math.floor(viewport.zoom); if (minZoom && z < minZoom) { return []; } viewport = new viewport.constructor(_objectSpread({}, viewport, { zoom: z })); var bbox = getBoundingBox(viewport); var _lngLatToWorld$map = (0, _viewportMercatorProject.lngLatToWorld)([bbox[0], bbox[3]], viewport.scale).map(pixelsToTileIndex), _lngLatToWorld$map2 = _slicedToArray(_lngLatToWorld$map, 2), minX = _lngLatToWorld$map2[0], minY = _lngLatToWorld$map2[1]; var _lngLatToWorld$map3 = (0, _viewportMercatorProject.lngLatToWorld)([bbox[2], bbox[1]], viewport.scale).map(pixelsToTileIndex), _lngLatToWorld$map4 = _slicedToArray(_lngLatToWorld$map3, 2), maxX = _lngLatToWorld$map4[0], maxY = _lngLatToWorld$map4[1]; var indices = []; for (var x = minX; x <= maxX; x++) { for (var y = minY; y <= maxY; y++) { if (maxZoom && z > maxZoom) { indices.push(getAdjustedTileIndex({ x: x, y: y, z: z }, maxZoom)); } else { indices.push({ x: x, y: y, z: z }); } } } return indices; } /** * Calculates and returns a new tile index {x, y, z}, with z being the given adjustedZ. */ function getAdjustedTileIndex(_ref, adjustedZ) { var x = _ref.x, y = _ref.y, z = _ref.z; var m = Math.pow(2, z - adjustedZ); return { x: Math.floor(x / m), y: Math.floor(y / m), z: adjustedZ }; } //# sourceMappingURL=viewport-util.js.map