add_touchPoint

packages/vx-event/src/touchPoint.js

@@ -0,0 +1,20 @@
+import { Point } from '@vx/point';
+export default function touchPoint(node, event) {
+  if (!node) return;
+  const svg = node.ownerSVGElement || node;
+  if (svg.createSVGPoint) {
+    let point = svg.createSVGPoint();
+    point.x = event.changedTouches[0].clientX;
+    point.y = event.changedTouches[0].clientY;
+    point = point.matrixTransform(node.getScreenCTM().inverse());
+    return new Point({
+      x: point.x,
+      y: point.y
+    });
+  }
+  const rect = node.getBoundingClientRect();
+  return new Point({
+    x: event.changedTouches[0].clientX - rect.left - node.clientLeft,
+    y: event.changedTouches[0].clientY - rect.top - node.clientTop
+  });
+}