Add joystick angle to position mapper

Change-Id: I427b02b656662aad7726ca264d73900f388f9ae3
diff --git a/y2019/joystick_angle.h b/y2019/joystick_angle.h
new file mode 100644
index 0000000..a2c7e36
--- /dev/null
+++ b/y2019/joystick_angle.h
@@ -0,0 +1,37 @@
+#ifndef Y2019_JOYSTICK_ANGLE_H_
+#define Y2019_JOYSTICK_ANGLE_H_
+
+#include "aos/input/driver_station_data.h"
+
+using ::aos::input::driver_station::JoystickAxis;
+using ::aos::input::driver_station::Data;
+
+namespace y2019 {
+namespace input {
+namespace joysticks {
+namespace {
+constexpr double kJoystickLeft = -0.5;
+constexpr double kJoystickRight = 0.5;
+constexpr double kJoystickUp = 0.5;
+constexpr double kJoystickDown = -0.5;
+}
+
+enum class JoystickAngle {
+  kDefault,
+  kUpperRight,
+  kMiddleRight,
+  kLowerRight,
+  kUpperLeft,
+  kMiddleLeft,
+  kLowerLeft
+};
+
+JoystickAngle GetJoystickPosition(const JoystickAxis &x_axis,
+                                  const JoystickAxis &y_axis, const Data &data);
+JoystickAngle GetJoystickPosition(float x_axis, float y_axis);
+
+}  // namespace joysticks
+}  // namespace input
+}  // namespace y2019
+
+#endif  // Y2019_JOYSTICK_ANGLE_H_