// always returns with normalized length
public static Vector2 Slerp(Vector2 fromV, Vector2 toV, float t) {
// oh god this little knot has so many hidden trig and sqrts.
var fromAng = fromV.Angle2D();
var toAng = toV.Angle2D();
float angleDelta = toAng - fromAng;
// make sure we're taking the shortest route
float flipper = angleDelta < 0f ? 360f : -360f;
float maybeFlip = Mathf.Abs(angleDelta) > 180f ? flipper : 0f;
float shortestDelta = angleDelta + maybeFlip;
float angleToMove = shortestDelta * t;
var newDir = fromV.RotateBy2D(angleToMove).normalized;
return newDir;
}
public static void DrawCapsule(Vector2 start, float radius, Vector2 dir, Color color, int numSegments = 20, float time = 0) {
var angle = dir.Angle2D();
DrawArc(start, radius, angle + 90, angle + 270, color, numSegments, time);
DrawArc(start + dir, radius, angle + 90, angle - 90, color, numSegments, time);
var leftDisplacement = dir.Left2D().normalized * radius;
Debug.DrawLine(start + leftDisplacement, start + dir + leftDisplacement, color, time);
Debug.DrawLine(start - leftDisplacement, start + dir - leftDisplacement, color, time);
}