refactor: packages/

1 files changed, 15 insertions, 0 deletions

diff --git a/packages/excalidraw/gesture.ts b/packages/excalidraw/gesture.ts
new file mode 100644
index 0000000..8ffa6d2
--- /dev/null
+++ b/packages/excalidraw/gesture.ts
@@ -0,0 +1,15 @@
+import type { PointerCoords } from "./types";
+
+export const getCenter = (pointers: Map<number, PointerCoords>) => {
+  const allCoords = Array.from(pointers.values());
+  return {
+    x: sum(allCoords, (coords) => coords.x) / allCoords.length,
+    y: sum(allCoords, (coords) => coords.y) / allCoords.length,
+  };
+};
+
+export const getDistance = ([a, b]: readonly PointerCoords[]) =>
+  Math.hypot(a.x - b.x, a.y - b.y);
+
+const sum = <T>(array: readonly T[], mapper: (item: T) => number): number =>
+  array.reduce((acc, item) => acc + mapper(item), 0);