fix: Draw shapefile exports as EPSG:31468 instead of WGS84 (needs work)

This is temporary; exports all shapefiles as EPSG:31468 instead of
correctly auto-sensing the proper CRS. That will come in a future update.

src/components/DrawingTool/DrawingTool.vue

@@ -36,6 +36,7 @@ de:
 <script lang="ts">
 import { Vue, Component, Watch, Prop } from 'vue-property-decorator'
 import { GeoJsonLayer, ScatterplotLayer } from '@deck.gl/layers'
+import proj4 from 'proj4'
 import ShapeWrite from 'shp-write'
 
 import LayerManager from '@/util/LayerManager'
@@ -143,9 +144,12 @@ export default class VueComponent extends Vue {
     this.points = []
     this.updateLayers()
 
+    // TEMP: convert to EPSG:31468 for VW demo
+    const convertPolygons = this.convertPolygons('EPSG:31468')
+
     const geojson = {
       type: 'FeatureCollection',
-      features: this.polygons,
+      features: convertPolygons,
     }
 
     ShapeWrite.download(geojson, {
@@ -160,6 +164,31 @@ export default class VueComponent extends Vue {
     this.startNewPolygon()
   }
 
+  private convertPolygons(crs: string) {
+    const convertedPolygons: any[] = []
+
+    console.log('CONVERTING')
+    console.log(this.polygons)
+    for (const p of this.polygons) {
+      const convertedPolygon = {
+        type: 'Feature',
+        geometry: {
+          type: 'Polygon',
+          coordinates: [[]] as any[],
+        },
+      }
+      for (const point of p.geometry.coordinates[0]) {
+        console.log(point)
+        const pointConverted = proj4('WGS84', crs, point)
+        convertedPolygon.geometry.coordinates[0].push(pointConverted)
+      }
+      convertedPolygons.push(convertedPolygon)
+    }
+
+    console.log({ convertedPolygons })
+    return convertedPolygons
+  }
+
   private cancel() {
     this.hint = this.$t('hint')
     this.clearShapes()