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node-red-contrib-tak-registration

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A Node-RED node to register to TAK and to help wrap files as datapackages to send to TAK

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/*! * MarchingSquaresJS * version 1.3.3 * https://github.com/RaumZeit/MarchingSquares.js * * @license GNU Affero General Public License. * Copyright (c) 2015-2019 Ronny Lorenz <ronny@tbi.univie.ac.at> */ (function (global, factory) { typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) : typeof define === 'function' && define.amd ? define(['exports'], factory) : (factory((global.MarchingSquaresJS = global.MarchingSquaresJS || {}))); }(this, (function (exports) { 'use strict'; /* * Compute the distance of a value 'v' from 'a' through linear interpolation * between the values of 'a' and 'b' * * Note, that we assume that 'a' and 'b' have unit distance (i.e. 1) */ function linear(a, b, v) { if (a < b) return (v - a) / (b - a); return (a - v) / (a - b); } function Options() { /* Settings common to all implemented algorithms */ this.successCallback = null; this.verbose = false; this.polygons = false; this.polygons_full = false; this.linearRing = true; this.noQuadTree = false; this.noFrame = false; } /* Compose settings specific to IsoLines algorithm */ function isoLineOptions(userSettings) { var i, key, val, lineOptions, optionKeys; lineOptions = new Options(); userSettings = userSettings ? userSettings : {}; optionKeys = Object.keys(lineOptions); for(i = 0; i < optionKeys.length; i++) { key = optionKeys[i]; val = userSettings[key]; if ((typeof val !== 'undefined') && (val !== null)) lineOptions[key] = val; } /* restore compatibility */ lineOptions.polygons_full = !lineOptions.polygons; /* add interpolation functions (not yet user customizable) */ lineOptions.interpolate = linear; return lineOptions; } function cell2Polygons(cell, x, y, settings) { var polygons = []; cell.polygons.forEach(function(p) { p.forEach(function(pp) { pp[0] += x; pp[1] += y; }); if (settings.linearRing) p.push(p[0]); polygons.push(p); }); return polygons; } function entry_coordinate(x, y, mode, path) { if (mode === 0) { /* down */ x += 1; y += path[0][1]; } else if (mode === 1) { /* left */ x += path[0][0]; } else if (mode === 2) { /* up */ y += path[0][1]; } else if (mode === 3) { /* right */ x += path[0][0]; y += 1; } return [ x, y ]; } function skip_coordinate(x, y, mode) { if (mode === 0) { /* down */ x++; } else if (mode === 1) ; else if (mode === 2) { /* up */ y++; } else if (mode === 3) { /* right */ x++; y++; } return [ x, y ]; } function requireLineFrame(data, threshold) { var frameRequired, cols, rows, i, j; frameRequired = true; cols = data[0].length; rows = data.length; for (j = 0; j < rows; j++) { if ((data[j][0] >= threshold) || (data[j][cols - 1] >= threshold)) { frameRequired = false; break; } } if ((frameRequired) && ((data[rows - 1][0] >= threshold) || (data[rows - 1][cols - 1] >= threshold))) { frameRequired = false; } if (frameRequired) for (i = 0; i < cols - 1; i++) { if ((data[0][i] >= threshold) || (data[rows - 1][i] > threshold)) { frameRequired = false; break; } } return frameRequired; } function traceLinePaths(data, cellGrid, settings) { var nextedge, e, ee, cc, path, enter, x, y, finalized, origin, point, dir, count, found_entry, ve; var polygons = []; var rows = data.length - 1; var cols = data[0].length - 1; /* * directions for out-of-grid moves are: * 0 ... "down", * 1 ... "left", * 2 ... "up", * 3 ... "right" */ var valid_entries = [ 'right', /* down */ 'bottom', /* left */ 'left', /* up */ 'top' /* right */ ]; var add_x = [ 0, -1, 0, 1 ]; var add_y = [ -1, 0, 1, 0 ]; var entry_dir = { bottom: 1, left: 2, top: 3, right: 0 }; /* first, detect whether we need any outer frame */ if (!settings.noFrame) if (requireLineFrame(data, settings.threshold)) { if (settings.linearRing) polygons.push([ [0, 0], [0, rows], [cols, rows], [cols, 0], [0, 0] ]); else polygons.push([ [0, 0], [0, rows], [cols, rows], [cols, 0] ]); } /* finally, start tracing back first polygon(s) */ cellGrid.forEach(function(a, i) { a.forEach(function(cell, j) { nextedge = null; /* trace paths for all available edges that go through this cell */ for (e = 0; e < 4; e++) { nextedge = valid_entries[e]; if (typeof cell.edges[nextedge] !== 'object') continue; /* start a new, full path */ path = []; ee = cell.edges[nextedge]; enter = nextedge; x = i; y = j; finalized = false; origin = [ i + ee.path[0][0], j + ee.path[0][1] ]; /* add start coordinate */ path.push(origin); /* start traceback */ while (!finalized) { cc = cellGrid[x][y]; if (typeof cc.edges[enter] !== 'object') break; ee = cc.edges[enter]; /* remove edge from cell */ delete cc.edges[enter]; /* add last point of edge to path arra, since we extend a polygon */ point = ee.path[1]; point[0] += x; point[1] += y; path.push(point); enter = ee.move.enter; x = x + ee.move.x; y = y + ee.move.y; /* handle out-of-grid moves */ if ((typeof cellGrid[x] === 'undefined') || (typeof cellGrid[x][y] === 'undefined')) { if (!settings.linearRing) break; dir = 0; count = 0; if (x === cols) { x--; dir = 0; /* move downwards */ } else if (x < 0) { x++; dir = 2; /* move upwards */ } else if (y === rows) { y--; dir = 3; /* move right */ } else if (y < 0) { y++; dir = 1; /* move left */ } if ((x === i) && (y === j) && (dir === entry_dir[nextedge])) { finalized = true; enter = nextedge; break; } while (1) { found_entry = false; if (count > 4) throw new Error('Direction change counter overflow! This should never happen!'); if (!((typeof cellGrid[x] === 'undefined') || (typeof cellGrid[x][y] === 'undefined'))) { cc = cellGrid[x][y]; /* check for re-entry */ ve = valid_entries[dir]; if (typeof cc.edges[ve] === 'object') { /* found re-entry */ ee = cc.edges[ve]; path.push(entry_coordinate(x, y, dir, ee.path)); enter = ve; found_entry = true; break; } } if (found_entry) { break; } else { path.push(skip_coordinate(x, y, dir)); x += add_x[dir]; y += add_y[dir]; /* change direction if we'e moved out of grid again */ if ((typeof cellGrid[x] === 'undefined') || (typeof cellGrid[x][y] === 'undefined')) { if (((dir === 0) && (y < 0)) || ((dir === 1) && (x < 0)) || ((dir === 2) && (y === rows)) || ((dir === 3) && (x === cols))) { x -= add_x[dir]; y -= add_y[dir]; dir = (dir + 1) % 4; count++; } } if ((x === i) && (y === j) && (dir === entry_dir[nextedge])) { /* we are back where we started off, so finalize the polygon */ finalized = true; enter = nextedge; break; } } } } } if ((settings.linearRing) && ((path[path.length - 1][0] !== origin[0]) || (path[path.length - 1][1] !== origin[1]))) path.push(origin); polygons.push(path); } /* end forall entry sites */ }); /* end foreach i */ }); /* end foreach j */ return polygons; } /* quadTree node constructor */ function TreeNode(data, x, y, dx, dy) { var dx_tmp = dx, dy_tmp = dy, msb_x = 0, msb_y = 0; /* left-bottom corner of current quadrant */ this.x = x; this.y = y; /* minimum value in subtree under this node */ this.lowerBound = null; /* maximum value in subtree under this node */ this.upperBound = null; /* * child nodes are layed out in the following way: * * (x, y + 1) ---- (x + 1, y + 1) * | | | * | D | C | * | | | * |----------------------------| * | | | * | A | B | * | | | * (x, y) ------------ (x + 1, y) */ this.childA = null; this.childB = null; this.childC = null; this.childD = null; if ((dx === 1) && (dy === 1)) { /* do not further subdivision */ this.lowerBound = Math.min( data[y][x], data[y][x + 1], data[y + 1][x + 1], data[y + 1][x] ); this.upperBound = Math.max( data[y][x], data[y][x + 1], data[y + 1][x + 1], data[y + 1][x] ); } else { /* get most significant bit from dx */ if (dx > 1) { while (dx_tmp !== 0) { dx_tmp = dx_tmp >> 1; msb_x++; } if (dx === (1 << (msb_x - 1))) msb_x--; dx_tmp = 1 << (msb_x - 1); } /* get most significant bit from dx */ if (dy > 1) { while (dy_tmp !== 0) { dy_tmp = dy_tmp >> 1; msb_y++; } if (dy === (1 << (msb_y - 1))) msb_y--; dy_tmp = 1 << (msb_y - 1); } this.childA = new TreeNode(data, x, y, dx_tmp, dy_tmp); this.lowerBound = this.childA.lowerBound; this.upperBound = this.childA.upperBound; if (dx - dx_tmp > 0) { this.childB = new TreeNode(data, x + dx_tmp, y, dx - dx_tmp, dy_tmp); this.lowerBound = Math.min(this.lowerBound, this.childB.lowerBound); this.upperBound = Math.max(this.upperBound, this.childB.upperBound); if (dy - dy_tmp > 0) { this.childC = new TreeNode(data, x + dx_tmp, y + dy_tmp, dx - dx_tmp, dy - dy_tmp); this.lowerBound = Math.min(this.lowerBound, this.childC.lowerBound); this.upperBound = Math.max(this.upperBound, this.childC.upperBound); } } if (dy - dy_tmp > 0) { this.childD = new TreeNode(data, x, y + dy_tmp, dx_tmp, dy - dy_tmp); this.lowerBound = Math.min(this.lowerBound, this.childD.lowerBound); this.upperBound = Math.max(this.upperBound, this.childD.upperBound); } } } /** * Retrieve a list of cells within a particular range of values by * recursivly traversing the quad tree to it's leaves. * * @param subsumed If 'true' include all cells that are completely * subsumed within the specified range. Otherwise, * return only cells where at least one corner is * outside the specified range. * * @return An array of objects 'o' where each object has exactly two * properties: 'o.x' and 'o.y' denoting the left-bottom corner * of the corresponding cell. */ TreeNode.prototype.cellsInBand = function(lowerBound, upperBound, subsumed) { var cells = []; subsumed = (typeof subsumed === 'undefined') ? true : subsumed; if ((this.lowerBound > upperBound) || (this.upperBound < lowerBound)) return cells; if (!(this.childA || this.childB || this.childC || this.childD)) { if ((subsumed) || (this.lowerBound <= lowerBound) || (this.upperBound >= upperBound)) { cells.push({ x: this.x, y: this.y }); } } else { if (this.childA) cells = cells.concat(this.childA.cellsInBand(lowerBound, upperBound, subsumed)); if (this.childB) cells = cells.concat(this.childB.cellsInBand(lowerBound, upperBound, subsumed)); if (this.childD) cells = cells.concat(this.childD.cellsInBand(lowerBound, upperBound, subsumed)); if (this.childC) cells = cells.concat(this.childC.cellsInBand(lowerBound, upperBound, subsumed)); } return cells; }; TreeNode.prototype.cellsBelowThreshold = function(threshold, subsumed) { var cells = []; subsumed = (typeof subsumed === 'undefined') ? true : subsumed; if (this.lowerBound > threshold) return cells; if (!(this.childA || this.childB || this.childC || this.childD)) { if ((subsumed) || (this.upperBound >= threshold)) { cells.push({ x: this.x, y: this.y }); } } else { if (this.childA) cells = cells.concat(this.childA.cellsBelowThreshold(threshold, subsumed)); if (this.childB) cells = cells.concat(this.childB.cellsBelowThreshold(threshold, subsumed)); if (this.childD) cells = cells.concat(this.childD.cellsBelowThreshold(threshold, subsumed)); if (this.childC) cells = cells.concat(this.childC.cellsBelowThreshold(threshold, subsumed)); } return cells; }; /* * Given a scalar field `data` construct a QuadTree * to efficiently lookup those parts of the scalar * field where values are within a particular * range of [lowerbound, upperbound] limits. */ function QuadTree(data) { var i, cols; /* do some input checking */ if (!data) throw new Error('data is required'); if (!Array.isArray(data) || !Array.isArray(data[0])) throw new Error('data must be scalar field, i.e. array of arrays'); if (data.length < 2) throw new Error('data must contain at least two rows'); /* check if we've got a regular grid */ cols = data[0].length; if (cols < 2) throw new Error('data must contain at least two columns'); for (i = 1; i < data.length; i++) { if (!Array.isArray(data[i])) throw new Error('Row ' + i + ' is not an array'); if (data[i].length != cols) throw new Error('unequal row lengths detected, please provide a regular grid'); } /* create pre-processing object */ this.data = data; /* root node, i.e. entry to the data */ this.root = new TreeNode(data, 0, 0, data[0].length - 1, data.length - 1); } /* eslint no-console: ["error", { allow: ["log"] }] */ /* * Compute the iso lines for a scalar 2D field given * a certain threshold by applying the Marching Squares * Algorithm. The function returns a list of path coordinates */ function isoLines(input, threshold, options) { var settings, i, j, useQuadTree = false, multiLine = false, tree = null, root = null, data = null, cellGrid = null, linePolygons = null, ret = []; /* validation */ if (!input) throw new Error('data is required'); if (threshold === undefined || threshold === null) throw new Error('threshold is required'); if ((!!options) && (typeof options !== 'object')) throw new Error('options must be an object'); /* process options */ settings = isoLineOptions(options); /* check for input data */ if (input instanceof QuadTree) { tree = input; root = input.root; data = input.data; if (!settings.noQuadTree) useQuadTree = true; } else if (Array.isArray(input) && Array.isArray(input[0])) { data = input; } else { throw new Error('input is neither array of arrays nor object retrieved from \'QuadTree()\''); } /* check and prepare input threshold(s) */ if (Array.isArray(threshold)) { multiLine = true; /* activate QuadTree optimization if not explicitly forbidden by user settings */ if (!settings.noQuadTree) useQuadTree = true; /* check if all minV are numbers */ for (i = 0; i < threshold.length; i++) if (isNaN(+threshold[i])) throw new Error('threshold[' + i + '] is not a number'); } else { if (isNaN(+threshold)) throw new Error('threshold must be a number or array of numbers'); threshold = [ threshold ]; } /* create QuadTree root node if not already present */ if ((useQuadTree) && (!root)) { tree = new QuadTree(data); root = tree.root; data = tree.data; } if (settings.verbose) { if(settings.polygons) console.log('MarchingSquaresJS-isoLines: returning single lines (polygons) for each grid cell'); else console.log('MarchingSquaresJS-isoLines: returning line paths (polygons) for entire data grid'); if (multiLine) console.log('MarchingSquaresJS-isoLines: multiple lines requested, returning array of line paths instead of lines for a single threshold'); } /* Done with all input validation, now let's start computing stuff */ /* loop over all threhsold values */ threshold.forEach(function(t, i) { linePolygons = []; /* store bounds for current computation in settings object */ settings.threshold = t; if(settings.verbose) console.log('MarchingSquaresJS-isoLines: computing iso lines for threshold ' + t); if (settings.polygons) { /* compose list of polygons for each single cell */ if (useQuadTree) { /* go through list of cells retrieved from QuadTree */ root .cellsBelowThreshold(settings.threshold, true) .forEach(function(c) { linePolygons = linePolygons.concat( cell2Polygons( prepareCell(data, c.x, c.y, settings), c.x, c.y, settings )); }); } else { /* go through entire array of input data */ for (j = 0; j < data.length - 1; ++j) { for (i = 0; i < data[0].length - 1; ++i) linePolygons = linePolygons.concat( cell2Polygons( prepareCell(data, i, j, settings), i, j, settings )); } } } else { /* sparse grid of input data cells */ cellGrid = []; for (i = 0; i < data[0].length - 1; ++i) cellGrid[i] = []; /* compose list of polygons for entire input grid */ if (useQuadTree) { /* collect the cells */ root .cellsBelowThreshold(settings.threshold, false) .forEach(function(c) { cellGrid[c.x][c.y] = prepareCell(data, c.x, c.y, settings); }); } else { /* prepare cells */ for (i = 0; i < data[0].length - 1; ++i) { for (j = 0; j < data.length - 1; ++j) { cellGrid[i][j] = prepareCell(data, i, j, settings); } } } linePolygons = traceLinePaths(data, cellGrid, settings); } /* finally, add polygons to output array */ if (multiLine) ret.push(linePolygons); else ret = linePolygons; if(typeof settings.successCallback === 'function') settings.successCallback(ret, t); }); return ret; } /* * Thats all for the public interface, below follows the actual * implementation */ /* * ################################ * Isocontour implementation below * ################################ */ function prepareCell(grid, x, y, settings) { var left, right, top, bottom, average, cell; var cval = 0; var x3 = grid[y + 1][x]; var x2 = grid[y + 1][x + 1]; var x1 = grid[y][x + 1]; var x0 = grid[y][x]; var threshold = settings.threshold; /* * Note that missing data within the grid will result * in horribly failing to trace full polygon paths */ if(isNaN(x0) || isNaN(x1) || isNaN(x2) || isNaN(x3)) { return; } /* * Here we detect the type of the cell * * x3 ---- x2 * | | * | | * x0 ---- x1 * * with edge points * * x0 = (x,y), * x1 = (x + 1, y), * x2 = (x + 1, y + 1), and * x3 = (x, y + 1) * * and compute the polygon intersections with the edges * of the cell. Each edge value may be (i) smaller, or (ii) * greater or equal to the iso line threshold. We encode * this property using 1 bit of information, where * * 0 ... below, * 1 ... above or equal * * Then we store the cells value as vector * * cval = (x0, x1, x2, x3) * * where x0 is the least significant bit (0th), * x1 the 2nd bit, and so on. This essentially * enables us to work with a single integer number */ cval |= ((x3 >= threshold) ? 8 : 0); cval |= ((x2 >= threshold) ? 4 : 0); cval |= ((x1 >= threshold) ? 2 : 0); cval |= ((x0 >= threshold) ? 1 : 0); /* make sure cval is a number */ cval = +cval; /* compose the cell object */ cell = { cval: cval, polygons: [], edges: {}, x0: x0, x1: x1, x2: x2, x3: x3 }; /* * Compute interpolated intersections of the polygon(s) * with the cell borders and (i) add edges for polygon * trace-back, or (ii) a list of small closed polygons */ switch (cval) { case 0: if (settings.polygons) cell.polygons.push([ [0, 0], [0, 1], [1, 1], [1, 0] ]); break; case 15: /* cell is outside (above) threshold, no polygons */ break; case 14: /* 1110 */ left = settings.interpolate(x0, x3, threshold); bottom = settings.interpolate(x0, x1, threshold); if (settings.polygons_full) { cell.edges.left = { path: [ [0, left], [bottom, 0] ], move: { x: 0, y: -1, enter: 'top' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, left], [bottom, 0] ]); break; case 13: /* 1101 */ bottom = settings.interpolate(x0, x1, threshold); right = settings.interpolate(x1, x2, threshold); if (settings.polygons_full) { cell.edges.bottom = { path: [ [bottom, 0], [1, right] ], move: { x: 1, y: 0, enter: 'left' } }; } if (settings.polygons) cell.polygons.push([ [bottom, 0], [1, right], [1, 0] ]); break; case 11: /* 1011 */ right = settings.interpolate(x1, x2, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.right = { path: [ [1, right], [top, 1] ], move: { x: 0, y: 1, enter: 'bottom' } }; } if (settings.polygons) cell.polygons.push([ [1, right], [top, 1], [1, 1] ]); break; case 7: /* 0111 */ left = settings.interpolate(x0, x3, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.top = { path: [ [top, 1], [0, left] ], move: { x: -1, y: 0, enter: 'right' } }; } if (settings.polygons) cell.polygons.push([ [top, 1], [0, left], [0, 1] ]); break; case 1: /* 0001 */ left = settings.interpolate(x0, x3, threshold); bottom = settings.interpolate(x0, x1, threshold); if (settings.polygons_full) { cell.edges.bottom = { path: [ [bottom, 0], [0, left] ], move: { x: -1, y: 0, enter: 'right' } }; } if (settings.polygons) cell.polygons.push([ [bottom, 0], [0, left], [0, 1], [1, 1], [1, 0] ]); break; case 2: /* 0010 */ bottom = settings.interpolate(x0, x1, threshold); right = settings.interpolate(x1, x2, threshold); if (settings.polygons_full) { cell.edges.right = { path: [ [1, right], [bottom, 0] ], move: { x: 0, y: -1, enter: 'top' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, 1], [1, 1], [1, right], [bottom, 0] ]); break; case 4: /* 0100 */ right = settings.interpolate(x1, x2, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.top = { path: [ [top, 1], [1, right] ], move: { x: 1, y: 0, enter: 'left' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, 1], [top, 1], [1, right], [1, 0] ]); break; case 8: /* 1000 */ left = settings.interpolate(x0, x3, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.left = { path: [ [0, left], [top, 1] ], move: { x: 0, y: 1, enter: 'bottom' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, left], [top, 1], [1, 1], [1, 0] ]); break; case 12: /* 1100 */ left = settings.interpolate(x0, x3, threshold); right = settings.interpolate(x1, x2, threshold); if (settings.polygons_full) { cell.edges.left = { path: [ [0, left], [1, right] ], move: { x: 1, y: 0, enter: 'left' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, left], [1, right], [1, 0] ]); break; case 9: /* 1001 */ bottom = settings.interpolate(x0, x1, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.bottom = { path: [ [bottom, 0], [top, 1] ], move: { x: 0, y: 1, enter: 'bottom' } }; } if (settings.polygons) cell.polygons.push([ [bottom, 0], [top, 1], [1, 1], [1, 0] ]); break; case 3: /* 0011 */ left = settings.interpolate(x0, x3, threshold); right = settings.interpolate(x1, x2, threshold); if (settings.polygons_full) { cell.edges.right = { path: [ [1, right], [0, left] ], move: { x: -1, y: 0, enter: 'right' } }; } if (settings.polygons) cell.polygons.push([ [0, left], [0, 1], [1, 1], [1, right] ]); break; case 6: /* 0110 */ bottom = settings.interpolate(x0, x1, threshold); top = settings.interpolate(x3, x2, threshold); if (settings.polygons_full) { cell.edges.top = { path: [ [top, 1], [bottom, 0] ], move: { x: 0, y: -1, enter: 'top' } }; } if (settings.polygons) cell.polygons.push([ [0, 0], [0, 1], [top, 1], [bottom, 0] ]); break; case 10: /* 1010 */ left = settings.interpolate(x0, x3, threshold); right = settings.interpolate(x1, x2, threshold); bottom = settings.interpolate(x0, x1, threshold); top = settings.interpolate(x3, x2, threshold); average = (x0 + x1 + x2 + x3) / 4; if (settings.polygons_full) { if (average < threshold) { cell.edges.left = { path: [ [0, left], [top, 1] ], move: { x: 0, y: 1, enter: 'bottom' } }; cell.edges.right = { path: [ [1, right], [bottom, 0] ], move: { x: 0, y: -1, enter: 'top' } }; } else { cell.edges.right = { path: [ [1, right], [top, 1] ], move: { x: 0, y: 1, enter: 'bottom' } }; cell.edges.left = { path: [ [0, left], [bottom, 0] ], move: { x: 0, y: -1, enter: 'top' } }; } } if (settings.polygons) { if (average < threshold) { cell.polygons.push([ [0, 0], [0, left], [top, 1], [1, 1], [1, right], [bottom, 0] ]); } else { cell.polygons.push([ [0, 0], [0, left], [bottom, 0] ]); cell.polygons.push([ [top, 1], [1, 1], [1, right] ]); } } break; case 5: /* 0101 */ left = settings.interpolate(x0, x3, threshold); right = settings.interpolate(x1, x2, threshold); bottom = settings.interpolate(x0, x1, threshold); top = settings.interpolate(x3, x2, threshold); average = (x0 + x1 + x2 + x3) / 4; if (settings.polygons_full) { if (average < threshold) { cell.edges.bottom = { path: [ [bottom, 0], [0, left] ], move: { x: -1, y: 0, enter: 'right' } }; cell.edges.top = { path: [ [top, 1], [1, right] ], move: { x: 1, y: 0, enter: 'left' } }; } else { cell.edges.top = { path: [ [top, 1], [0, left] ], move: { x: -1, y: 0, enter: 'right' } }; cell.edges.bottom = { path: [ [bottom, 0], [1, right] ], move: { x: 1, y: 0, enter: 'left' } }; } } if (settings.polygons) { if (average < threshold) { cell.polygons.push([ [0, left], [0, 1], [top, 1], [1, right], [1, 0], [bottom, 0] ]); } else { cell.polygons.push([ [0, left], [0, 1], [top, 1] ]); cell.polygons.push([ [bottom, 0], [1, right], [1, 0] ]); } } break; } return cell; } exports.isoLines = isoLines; exports.isoContours = isoLines; Object.defineProperty(exports, '__esModule', { value: true }); })));