Updating Gamepad API to match latest spec

content/browser/gamepad/gamepad_standard_mappings.cc

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/gamepad/gamepad_standard_mappings.h"
+
+namespace content {
+
+blink::WebGamepadButton AxisToButton(float input) {
+  float value = (input + 1.f) / 2.f;
+  return blink::WebGamepadButton(
+    value > kDefaultButtonPressedThreshold, value);
+}
+
+blink::WebGamepadButton AxisNegativeAsButton(float input) {
+  float value = (input < -0.5f) ? 1.f : 0.f;
+  return blink::WebGamepadButton(
+    value > kDefaultButtonPressedThreshold, value);
+}
+
+blink::WebGamepadButton AxisPositiveAsButton(float input) {
+  float value = (input > 0.5f) ? 1.f : 0.f;
+  return blink::WebGamepadButton(
+    value > kDefaultButtonPressedThreshold, value);
+}
+
+void DpadFromAxis(blink::WebGamepad* mapped, float dir) {
+  bool up = false;
+  bool right = false;
+  bool down = false;
+  bool left = false;
+
+  // Dpad is mapped as a direction on one axis, where -1 is up and it
+  // increases clockwise to 1, which is up + left. It's set to a large (> 1.f)
+  // number when nothing is depressed, except on start up, sometimes it's 0.0
+  // for no data, rather than the large number.
+  if (dir != 0.0f) {
+    up = (dir >= -1.f && dir < -0.7f) || (dir >= .95f && dir <= 1.f);
+    right = dir >= -.75f && dir < -.1f;
+    down = dir >= -.2f && dir < .45f;
+    left = dir >= .4f && dir <= 1.f;
+  }
+
+  mapped->buttons[kButtonDpadUp].pressed = up;
+  mapped->buttons[kButtonDpadUp].value = up ? 1.f : 0.f;
+  mapped->buttons[kButtonDpadRight].pressed = right;
+  mapped->buttons[kButtonDpadRight].value = right ? 1.f : 0.f;
+  mapped->buttons[kButtonDpadDown].pressed = down;
+  mapped->buttons[kButtonDpadDown].value = down ? 1.f : 0.f;
+  mapped->buttons[kButtonDpadLeft].pressed = left;
+  mapped->buttons[kButtonDpadLeft].value = left ? 1.f : 0.f;
+}
+
+}  // namespace content