Display delta heigth stats for trkseg

src/lib/height.ts

@@ -0,0 +1,33 @@
+export const getHeightStats = (wpts: Wpt[]) => {
+  let previous: number | null = null,
+    min: number | null = null,
+    max: number | null = null,
+    positive: number = 0,
+    negative: number = 0;
+
+  wpts.forEach((wpt) => {
+    if (wpt.ele) {
+      const ele = Math.round(wpt.ele);
+      if (!max || ele > max) {
+        max = ele;
+      }
+      if (!min || ele < min) {
+        min = ele;
+      }
+      if (previous) {
+        if (ele > previous) {
+          positive += ele - previous;
+        } else {
+          negative += previous - ele;
+        }
+      }
+      previous = ele;
+    }
+  });
+  return { min, max, positive, negative };
+};
+
+export const getFormattedHeightStats = (wpts: Wpt[]) => {
+  const { min, max, positive, negative } = getHeightStats(wpts);
+  return `d+ : ${positive}m, d- : ${negative}m`;
+};

src/lib/ol.ts

@@ -1,7 +1,7 @@
 import { LineString } from 'ol/geom';
 import { getLength } from 'ol/sphere';
 
-export const getFormatedLength = (lineString: LineString) => {
+export const getFormattedLength = (lineString: LineString) => {
   const length = getLength(lineString, { projection: 'EPSG:4326' });
   if (length > 1000) {
     const l = length / 1000;