From 58b780563c7fc4a1496f5c676f2d14faddb096e0 Mon Sep 17 00:00:00 2001 From: Melissa Zhang Date: Fri, 3 Jul 2020 17:32:40 -0700 Subject: merge with master --- src/pen-gestures/ndollar.ts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/pen-gestures') diff --git a/src/pen-gestures/ndollar.ts b/src/pen-gestures/ndollar.ts index 9d42035d1..ecd8df3e7 100644 --- a/src/pen-gestures/ndollar.ts +++ b/src/pen-gestures/ndollar.ts @@ -552,7 +552,7 @@ function Distance(p1: any, p2: any) // distance between two points } function CalcStartUnitVector(points: any, index: any) // start angle from points[0] to points[index] normalized as a unit vector { - const v = new Point(points[index].X - points[0].X, points[index].Y - points[0].Y); + const v = new Point(points[index]?.X - points[0]?.X, points[index]?.Y - points[0]?.Y); const len = Math.sqrt(v.X * v.X + v.Y * v.Y); return new Point(v.X / len, v.Y / len); } -- cgit v1.2.3-70-g09d2