Support DirectInput gamepads on Windows.

content/browser/gamepad/gamepad_standard_mappings_win.cc

+// Copyright (c) 2012 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"
+
+#include "content/common/gamepad_hardware_buffer.h"
+
+namespace content {
+
+namespace {
+
+// Maps 0..65535 to -1..1.
+float NormalizeDirectInputAxis(long value) {
+  return (value * 1.f / 32767.5f) - 1.f;
+}
+
+void MapperDragonRiseGeneric(
+    const WebKit::WebGamepad& input,
+    WebKit::WebGamepad* mapped) {
+  *mapped = input;
+  mapped->buttons[0] = input.buttons[1];
+  mapped->buttons[1] = input.buttons[2];
+  mapped->buttons[2] = input.buttons[0];
+  mapped->buttons[12] = input.buttons[16];
+  mapped->buttons[13] = input.buttons[17];
+  mapped->buttons[14] = input.buttons[18];
+  mapped->buttons[15] = input.buttons[19];
+  mapped->buttonsLength = 16;
+  mapped->axes[0] = NormalizeDirectInputAxis(input.axes[0]);
+  mapped->axes[1] = NormalizeDirectInputAxis(input.axes[1]);
+  mapped->axes[2] = NormalizeDirectInputAxis(input.axes[2]);
+  mapped->axes[3] = NormalizeDirectInputAxis(input.axes[5]);
+  mapped->axesLength = 4;
+}
+
+struct MappingData {
+  const char* const vendor_id;
+  const char* const product_id;
+  GamepadStandardMappingFunction function;
+} AvailableMappings[] = {
+  // http://www.linux-usb.org/usb.ids
+  { "0079", "0006", MapperDragonRiseGeneric }, // DragonRise Generic USB
+};
+
+}  // namespace
+
+GamepadStandardMappingFunction GetGamepadStandardMappingFunction(
+    const base::StringPiece& vendor_id,
+    const base::StringPiece& product_id) {
+  for (size_t i = 0; i < arraysize(AvailableMappings); ++i) {
+    MappingData& item = AvailableMappings[i];
+    if (vendor_id == item.vendor_id && product_id == item.product_id)
+      return item.function;
+  }
+  return NULL;
+}
+
+}  // namespace content