Added triangulation

LICENCE.md

@@ -47,3 +47,21 @@ shp.ts uses the following third-party code:
 > LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 > OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 > SOFTWARE.
+
+### [mapbox earcut](https://github.com/mapbox/earcut)
+
+> ISC License
+>
+> Copyright (c) 2016, Mapbox
+>
+> Permission to use, copy, modify, and/or distribute this software for any purpose
+> with or without fee is hereby granted, provided that the above copyright notice
+> and this permission notice appear in all copies.
+>
+> THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+> REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+> FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+> INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+> OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+> TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+> THIS SOFTWARE.

README.md

@@ -1,20 +1,24 @@
 # SHP.ts 🗺️
 
-<sup>⚠️☕️ Careful, still hot, very early stages of development, consume with caution</sup>
-
-TypeScript package for loading Esri Shapefiles.
+TypeScript package for loading Esri Shapefiles, primary developed for for WebGL applications
 
 -   ✅ returns a geojson-like representation
 -   ✅ supports all shape types (including MultiPatch) per [Esri Shapefile specification](https://www.esri.com/content/dam/esrisites/sitecore-archive/Files/Pdfs/library/whitepapers/pdfs/shapefile.pdf)
 -   ✅ supports X, Y, Z, and M coordinates
 -   ✅ uses vitest 🧪 for testing
+-   ✅ includes mapbox's earcut triangulation
 
 ## Install from [npm](https://www.npmjs.com/package/shpts)
 
 ```
 npm install shpts
 ```
 
+| Branch  |                                                                                                                                                                          |
+| ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
+| Release | [![SHPts CI Release](https://github.com/vojtatom/shpts/actions/workflows/ci.yaml/badge.svg?branch=release)](https://github.com/vojtatom/shpts/actions/workflows/ci.yaml) |
+| Dev     | [![SHPts CI Dev](https://github.com/vojtatom/shpts/actions/workflows/ci.yaml/badge.svg?branch=dev)](https://github.com/vojtatom/shpts/actions/workflows/ci.yaml)         |
+
 ## Usage
 
 ```typescript
@@ -64,6 +68,23 @@ const properties = reader.readRecord(index);
 console.log(properties);
 ```
 
+triangulate a polygon (expects a set of rings, where the first one is the outer ring and the rest are holes):
+
+```typescript
+import { triangulate, Ring } from 'shpts';
+
+const input: Ring[] = [
+    [
+        [0, 0],
+        [1, 0],
+        [1, 1],
+        [0, 1],
+    ],
+];
+const output = triangulate(input, CoordType.XY);
+//Float32Array([1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1])
+```
+
 ## Credits
 
 -   insipred by https://github.com/oyvindi/ts-shapefile (MIT Licence), uses all of its test data, partially uses its code

package.json

@@ -1,7 +1,7 @@
 {
     "name": "shpts",
     "private": false,
-    "version": "1.0.4",
+    "version": "1.0.5",
     "type": "module",
     "repository": {
         "type": "git",
@@ -43,5 +43,8 @@
         "vite": "^4.1.0",
         "vite-plugin-dts": "^2.0.0-beta.3",
         "vitest": "^0.30.1"
+    },
+    "dependencies": {
+        "gl-matrix": "^3.4.3"
     }
 }

shpts/geometry/multipatch.ts

@@ -93,7 +93,9 @@ export class MultiPatchRecord extends BaseRingedRecord {
         let offsetFirst = 1;
         let offsetSecond = 2;
         for (let i = 0; i < coords.length - 2; i++) {
-            polygons.push([[coords[i], coords[i + offsetFirst], coords[i + offsetSecond]]]);
+            polygons.push([
+                [coords[i], coords[i + offsetFirst], coords[i + offsetSecond], coords[i]],
+            ]);
             offsetFirst = offsetFirst === 1 ? 2 : 1;
             offsetSecond = offsetSecond === 1 ? 2 : 1;
         }
@@ -103,7 +105,7 @@ export class MultiPatchRecord extends BaseRingedRecord {
     private static triangleFanToPolygon(coords: Coord[]) {
         const polygons = [];
         for (let i = 1; i < coords.length - 1; i++) {
-            polygons.push([[coords[0], coords[i], coords[i + 1]]]);
+            polygons.push([[coords[0], coords[i], coords[i + 1], coords[0]]]);
         }
         return polygons;
     }

shpts/reader/featureReader.ts

@@ -56,14 +56,16 @@ export class FeatureReader {
         let attrs = [];
         if (this.dbfReader != null) attrs = this.dbfReader.readRecord(index);
 
+        if (geom == null) return null;
+
         return new Feature(geom, attrs, this.dbfReader?.fields);
     }
 
     public readFeatureCollection() {
         const collection = new FeatureCollection();
         for (let i = 0; i < this.featureCount; i++) {
             const feature = this.readFeature(i);
-            collection.features.push(feature);
+            if (feature != null) collection.features.push(feature);
         }
         return collection;
     }

shpts/reader/shpReader.ts

@@ -92,6 +92,14 @@ export class ShapeReader {
     }
 
     readGeom(geomIndex: number) {
+        try {
+            return this.readGeometryData(geomIndex);
+        } catch (e: any) {
+            return null;
+        }
+    }
+
+    private readGeometryData(geomIndex: number) {
         const offset = this.getShpIndex(geomIndex);
         this.shpStream.seek(offset);
         const recHead = this.readGeomHeader();

shpts/shpts.ts

@@ -11,6 +11,7 @@ import { MultiPatchRecord } from './geometry/multipatch';
 import { DbfRecord } from './table/record';
 import { DbfFieldDescr, DbfFieldType } from './types/dbfTypes';
 import { Coord, CoordType } from './types/coordinate';
+import { triangulate } from './utils/triangulation';
 
 export {
     DbfReader,
@@ -25,6 +26,7 @@ export {
     MultiPointRecord,
     MultiPatchRecord,
     CoordType,
+    triangulate,
 };
 
 export type { DbfFieldType, DbfFieldDescr, Coord };

shpts/types/coordinate.ts

@@ -14,5 +14,5 @@ export type PointCoord = Coord;
 export type MultiPointCoord = Coord[];
 export type PolyLineCoord = Coord[][];
 export type Ring = Coord[];
-export type PolygonCoord = Coord[][][];
-export type MultiPatchCoord = Coord[][][];
+export type PolygonCoord = Ring[][];
+export type MultiPatchCoord = Ring[][];