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Support PointZ, PolyLineZ and PolygonZ #55

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8 changes: 7 additions & 1 deletion src/extent.js
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Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,8 @@ module.exports.enlarge = function enlargeExtent(extent, pt) {
if (pt[0] > extent.xmax) extent.xmax = pt[0];
if (pt[1] < extent.ymin) extent.ymin = pt[1];
if (pt[1] > extent.ymax) extent.ymax = pt[1];
if (pt[2] && pt[2] < extent.zmin) extent.zmin = pt[2];
if (pt[2] && pt[2] > extent.zmax) extent.zmax = pt[2];
return extent;
};

Expand All @@ -11,14 +13,18 @@ module.exports.enlargeExtent = function enlargeExtent(extent, ext) {
if (ext.xmin < extent.xmin) extent.xmin = ext.xmin;
if (ext.ymax > extent.ymax) extent.ymax = ext.ymax;
if (ext.ymin < extent.ymin) extent.ymin = ext.ymin;
if (ext.zmax && ext.zmax > extent.zmax) extent.zmax = ext.zmax;
if (ext.zmin && ext.zmin < extent.zmin) extent.zmin = ext.zmin;
return extent;
};

module.exports.blank = function() {
return {
xmin: Number.MAX_VALUE,
ymin: Number.MAX_VALUE,
zmin: Number.MAX_VALUE,
xmax: -Number.MAX_VALUE,
ymax: -Number.MAX_VALUE
ymax: -Number.MAX_VALUE,
zmax: -Number.MAX_VALUE
};
};
38 changes: 31 additions & 7 deletions src/geojson.js
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Original file line number Diff line number Diff line change
@@ -1,13 +1,21 @@
module.exports.point = justType('Point', 'POINT');
module.exports.line = justType('LineString', 'POLYLINE');
module.exports.polygon = justType('Polygon', 'POLYGON');
module.exports.point = justType('Point', 'POINT', false);
module.exports.pointZ = justType('Point', 'POINTZ', true);
module.exports.line = justType('LineString', 'POLYLINE', false);
module.exports.lineZ = justType('LineString', 'POLYLINEZ', true);
module.exports.polygon = justType('Polygon', 'POLYGON', false);
module.exports.polygonZ = justType('Polygon', 'POLYGONZ', true);

function justType(type, TYPE) {
function justType(type, TYPE, just3d) {
return function(gj) {
var oftype = gj.features.filter(isType(type));
var ofType = gj.features.filter(isType(type));
var ofDimension = ofType.filter(isOfDimension(TYPE, just3d));

return {
geometries: (TYPE === 'POLYGON' || TYPE === 'POLYLINE') ? [oftype.map(justCoords)] : oftype.map(justCoords),
properties: oftype.map(justProps),
geometries: (TYPE === 'POLYLINE' || TYPE === 'POLYLINEZ' ||
TYPE === 'POLYGON' || TYPE === 'POLYGONZ') ?
[ofDimension.map(justCoords)] :
ofDimension.map(justCoords),
properties: ofDimension.map(justProps),
type: TYPE
};
};
Expand All @@ -17,6 +25,7 @@ function justCoords(t) {
if (t.geometry.coordinates[0] !== undefined &&
t.geometry.coordinates[0][0] !== undefined &&
t.geometry.coordinates[0][0][0] !== undefined) {
// Unwraps rings
return t.geometry.coordinates[0];
} else {
return t.geometry.coordinates;
Expand All @@ -30,3 +39,18 @@ function justProps(t) {
function isType(t) {
return function(f) { return f.geometry.type === t; };
}

function isOfDimension(TYPE, just3d) {
return function(f) {
var coordinates;
if (TYPE === 'POINT' || TYPE === 'POINTZ') {
coordinates = f.geometry.coordinates;
}
else {
coordinates = Array.isArray(f.geometry.coordinates[0][0]) ?
f.geometry.coordinates[0][0] :
f.geometry.coordinates[0];
}
return just3d ? coordinates.length === 3 : coordinates.length === 2;
}
}
33 changes: 22 additions & 11 deletions src/points.js
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Original file line number Diff line number Diff line change
@@ -1,28 +1,35 @@
var ext = require('./extent');
var types = require('./types');

module.exports.write = function writePoints(coordinates, extent, shpView, shxView) {

var contentLength = 28, // 8 header, 20 content
fileLength = 100,
var
fileLength = 100, // starts with 100 as this is the fixed header length
shpI = 0,
shxI = 0;

coordinates.forEach(function writePoint(coords, i) {
coordinates.forEach(function writePoint(coords, index) {
var is3d = !!coords[2],
contentLength = is3d ? 44 : 28; // 8 header + 20 content, 8 header + 36 content when 3d
// HEADER
// 4 record number
// 4 content length in 16-bit words (20/2)
shpView.setInt32(shpI, i);
shpView.setInt32(shpI + 4, 10);
shpView.setInt32(shpI, index);
shpView.setInt32(shpI + 4, (contentLength - 8) / 2);

// record
// (8 + 8) + 4 = 20 content length
shpView.setInt32(shpI + 8, 1, true); // POINT=1
shpView.setFloat64(shpI + 12, coords[0], true); // X
shpView.setFloat64(shpI + 20, coords[1], true); // Y
// For 3d (8 + 8 + 8) + 4 = 28 content length
shpView.setInt32(shpI + 8, (is3d ? types.geometries.POINTZ : types.geometries.POINT), true); // 4
shpView.setFloat64(shpI + 12, coords[0], true); // X // 8
shpView.setFloat64(shpI + 20, coords[1], true); // Y // 8
if (is3d) {
shpView.setFloat64(shpI + 28, coords[2], true); // Z // 8
shpView.setFloat64(shpI + 36, Math.pow(38, -10) - 1, true); // M // 8
}

// index
shxView.setInt32(shxI, fileLength / 2); // length in 16-bit words
shxView.setInt32(shxI + 4, 10);
shxView.setInt32(shxI + 4, is3d ? 18 : 10);

shxI += 8;
shpI += contentLength;
Expand All @@ -45,5 +52,9 @@ module.exports.shxLength = function(coordinates) {
};

module.exports.shpLength = function(coordinates) {
return coordinates.length * 28;
// header: 8 bytes + shape type (4 bytes) +
// either 2 * 8 bytes (XY) or 4 * 8 bytes (XYZM)
return coordinates.reduce(function(length, coordinate) {
return length + coordinate.length === 3 ? 44 : 28;
}, 0);
};
47 changes: 35 additions & 12 deletions src/poly.js
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Original file line number Diff line number Diff line change
Expand Up @@ -13,15 +13,23 @@ module.exports.write = function writePoints(geometries, extent, shpView, shxView

var flattened = justCoords(coordinates),
noParts = parts([coordinates], TYPE),
contentLength = (flattened.length * 16) + 48 + (noParts - 1) * 4;
contentLength = (flattened.length * 16) + 48 + (noParts - 1) * 4,
is3d = !!flattened[0][2];

// For a 3d shape the following additional information is present:
// ZMin, ZMax (8 bytes each)
// ZArray (8 bytes per point)
if (is3d) {
contentLength += 16 + flattened.length * 8;
}

var featureExtent = flattened.reduce(function(extent, c) {
return ext.enlarge(extent, c);
}, ext.blank());

// INDEX
shxView.setInt32(shxI, shxOffset / 2); // offset
shxView.setInt32(shxI + 4, contentLength / 2); // offset length
shxView.setInt32(shxI + 4, contentLength / 2); // content length

shxI += 8;
shxOffset += contentLength + 8;
Expand Down Expand Up @@ -55,19 +63,39 @@ module.exports.write = function writePoints(geometries, extent, shpView, shxView
);
}

// Points
flattened.forEach(function writeLine(coords, i) {
shpView.setFloat64(shpI + 56 + (i * 16) + (noParts - 1) * 4, coords[0], true); // X
shpView.setFloat64(shpI + 56 + (i * 16) + (noParts - 1) * 4 + 8, coords[1], true); // Y
});

if (is3d) {
// Byte position Y as in spec
var y = (shpI + 56 + (i * 16) + (noParts - 1) * 4) + 16 * flattened.length;

shpView.setFloat64(y, featureExtent.zmin, true);
shpView.setFloat64(y + 8, featureExtent.zmax, true);
flattened.forEach(function writeZArray(point, index) {
shpView.setFloat64(y + 16 + index * 8, point[2], true);
});
}

shpI += contentLength + 8;
}
};

module.exports.shpLength = function(geometries) {
// NOTE: parts array length should not be included
// as this is calculated in write.js

var flattened = justCoords(geometries),
is3d = !!flattened[0][2];

// geometry base length = 56 (up to points, including 8 byte record header)
return (geometries.length * 56) +
// points
(justCoords(geometries).length * 16);
(flattened.length * 16) +
(is3d ? 16 + flattened.length * 8 : 0);
};

module.exports.shxLength = function(geometries) {
Expand All @@ -82,7 +110,9 @@ module.exports.extent = function(coordinates) {

function parts(geometries, TYPE) {
var no = 1;
if (TYPE === types.geometries.POLYGON || TYPE === types.geometries.POLYLINE) {
if (TYPE === types.geometries.POLYGON || TYPE === types.geometries.POLYGONZ ||
TYPE === types.geometries.POLYLINE || TYPE === types.geometries.POLYLINEZ)
{
no = geometries.reduce(function (no, coords) {
no += coords.length;
if (Array.isArray(coords[0][0][0])) { // multi
Expand All @@ -98,20 +128,13 @@ function parts(geometries, TYPE) {

module.exports.parts = parts;

function totalPoints(geometries) {
var sum = 0;
geometries.forEach(function(g) { sum += g.length; });
return sum;
}

function justCoords(coords, l) {
if (l === undefined) l = [];
if (typeof coords[0][0] == 'object') {
if (typeof coords[0][0] === 'object') {
return coords.reduce(function(memo, c) {
return memo.concat(justCoords(c));
}, l);
} else {
return coords;
}
}

13 changes: 10 additions & 3 deletions src/write.js
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Original file line number Diff line number Diff line change
Expand Up @@ -8,9 +8,12 @@ var types = require('./types'),
polyWriter = require('./poly');

var writers = {
1: pointWriter,
5: polyWriter,
3: polyWriter
1: pointWriter, // Point
3: polyWriter, // PolyLine
5: polyWriter, // Polygon
11: pointWriter, // PointZ
13: polyWriter, // PolyLineZ
15: polyWriter // PolygonZ
};

var recordHeaderLength = 8;
Expand Down Expand Up @@ -65,4 +68,8 @@ function writeExtent(extent, view) {
view.setFloat64(44, extent.ymin, true);
view.setFloat64(52, extent.xmax, true);
view.setFloat64(60, extent.ymax, true);
view.setFloat64(68, extent.zmin, true);
view.setFloat64(76, extent.zmax, true);
view.setFloat64(84, 0.0, true); // Measure not supported, so always set to 0
view.setFloat64(92, 0.0, true); // Measure not supported, so always set to 0
}
2 changes: 1 addition & 1 deletion src/zip.js
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Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@ module.exports = function(gj, options) {
var zip = new JSZip(),
layers = zip.folder(options && options.folder ? options.folder : 'layers');

[geojson.point(gj), geojson.line(gj), geojson.polygon(gj)]
[geojson.point(gj), geojson.pointZ(gj), geojson.line(gj), geojson.lineZ(gj), geojson.polygon(gj), geojson.polygonZ(gj)]
.forEach(function(l) {
if (l.geometries.length && l.geometries[0].length) {
write(
Expand Down