content/browser/gamepad/gamepad_platform_data_fetcher_android.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/gamepad/gamepad_platform_data_fetcher_android.h"
   6
   7 #include "base/android/jni_android.h"
   8 #include "base/android/jni_array.h"
   9 #include "base/android/jni_string.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/string_util.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "base/trace_event/trace_event.h"
  14
  15 #include "jni/GamepadList_jni.h"
  16
  17 #include "third_party/WebKit/public/platform/WebGamepads.h"
  18
  19 using base::android::AttachCurrentThread;
  20 using base::android::CheckException;
  21 using base::android::ClearException;
  22 using base::android::ConvertJavaStringToUTF8;
  23 using base::android::ScopedJavaLocalRef;
  24 using blink::WebGamepad;
  25 using blink::WebGamepads;
  26
  27 namespace content {
  28
  29 bool
  30 GamepadPlatformDataFetcherAndroid::RegisterGamepadPlatformDataFetcherAndroid(
  31     JNIEnv* env) {
  32   return RegisterNativesImpl(env);
  33 }
  34
  35 GamepadPlatformDataFetcherAndroid::GamepadPlatformDataFetcherAndroid() {
  36   PauseHint(false);
  37 }
  38
  39 GamepadPlatformDataFetcherAndroid::~GamepadPlatformDataFetcherAndroid() {
  40   PauseHint(true);
  41 }
  42
  43 void GamepadPlatformDataFetcherAndroid::GetGamepadData(
  44     blink::WebGamepads* pads,
  45     bool devices_changed_hint) {
  46   TRACE_EVENT0("GAMEPAD", "GetGamepadData");
  47
  48   pads->length = 0;
  49
  50   JNIEnv* env = AttachCurrentThread();
  51   if (!env)
  52     return;
  53
  54   Java_GamepadList_updateGamepadData(env, reinterpret_cast<intptr_t>(pads));
  55 }
  56
  57 void GamepadPlatformDataFetcherAndroid::PauseHint(bool paused) {
  58   JNIEnv* env = AttachCurrentThread();
  59   if (!env)
  60     return;
  61
  62   Java_GamepadList_setGamepadAPIActive(env, !paused);
  63 }
  64
  65 static void SetGamepadData(JNIEnv* env,
  66                            const JavaParamRef<jobject>& obj,
  67                            jlong gamepads,
  68                            jint index,
  69                            jboolean mapping,
  70                            jboolean connected,
  71                            const JavaParamRef<jstring>& devicename,
  72                            jlong timestamp,
  73                            const JavaParamRef<jfloatArray>& jaxes,
  74                            const JavaParamRef<jfloatArray>& jbuttons) {
  75   DCHECK(gamepads);
  76   blink::WebGamepads* pads = reinterpret_cast<WebGamepads*>(gamepads);
  77   DCHECK_EQ(pads->length, unsigned(index));
  78   DCHECK_LT(index, static_cast<int>(blink::WebGamepads::itemsLengthCap));
  79
  80   ++pads->length;
  81
  82   blink::WebGamepad& pad = pads->items[index];
  83
  84   pad.connected = connected;
  85
  86   pad.timestamp = timestamp;
  87
  88   // Do not set gamepad parameters for all the gamepad devices that are not
  89   // attached.
  90   if (!connected)
  91     return;
  92
  93   // Map the Gamepad DeviceName String to the WebGamepad Id. Ideally it should
  94   // be mapped to vendor and product information but it is only available at
  95   // kernel level and it can not be queried using class
  96   // android.hardware.input.InputManager.
  97   // TODO(SaurabhK): Store a cached WebGamePad object in
  98   // GamepadPlatformDataFetcherAndroid and only update constant WebGamepad
  99   // values when a device has changed.
 100   base::string16 device_name;
 101   base::android::ConvertJavaStringToUTF16(env, devicename, &device_name);
 102   const size_t name_to_copy =
 103       std::min(device_name.size(), WebGamepad::idLengthCap - 1);
 104   memcpy(pad.id,
 105          device_name.data(),
 106          name_to_copy * sizeof(base::string16::value_type));
 107   pad.id[name_to_copy] = 0;
 108
 109   base::string16 mapping_name = base::UTF8ToUTF16(mapping ? "standard" : "");
 110   const size_t mapping_to_copy =
 111       std::min(mapping_name.size(), WebGamepad::mappingLengthCap - 1);
 112   memcpy(pad.mapping,
 113          mapping_name.data(),
 114          mapping_to_copy * sizeof(base::string16::value_type));
 115   pad.mapping[mapping_to_copy] = 0;
 116
 117   pad.timestamp = timestamp;
 118
 119   std::vector<float> axes;
 120   base::android::JavaFloatArrayToFloatVector(env, jaxes, &axes);
 121
 122   // Set WebGamepad axeslength to total number of axes on the gamepad device.
 123   // Only return the first axesLengthCap if axeslength captured by GamepadList
 124   // is larger than axesLengthCap.
 125   pad.axesLength = std::min(static_cast<int>(axes.size()),
 126                             static_cast<int>(WebGamepad::axesLengthCap));
 127
 128   // Copy axes state to the WebGamepad axes[].
 129   for (unsigned int i = 0; i < pad.axesLength; i++) {
 130     pad.axes[i] = static_cast<double>(axes[i]);
 131   }
 132
 133   std::vector<float> buttons;
 134   base::android::JavaFloatArrayToFloatVector(env, jbuttons, &buttons);
 135
 136   // Set WebGamepad buttonslength to total number of axes on the gamepad
 137   // device. Only return the first buttonsLengthCap if axeslength captured by
 138   // GamepadList is larger than buttonsLengthCap.
 139   pad.buttonsLength = std::min(static_cast<int>(buttons.size()),
 140                                static_cast<int>(WebGamepad::buttonsLengthCap));
 141
 142   // Copy buttons state to the WebGamepad buttons[].
 143   for (unsigned int j = 0; j < pad.buttonsLength; j++) {
 144     pad.buttons[j].pressed = buttons[j];
 145     pad.buttons[j].value = buttons[j];
 146   }
 147 }
 148
 149 }  // namespace content