Gamepad API support for chrome on android

content/browser/android/gamepad_reader_impl.cc

+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of NVIDIA CORPORATION nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include "base/android/jni_android.h"
+#include "base/android/jni_string.h"
+#include "content/browser/android/gamepad_reader_impl.h"
+
+#include "jni/GamepadList_jni.h"
+
+using base::android::AttachCurrentThread;
+using base::android::CheckException;
+using base::android::ClearException;
+using base::android::ConvertJavaStringToUTF8;
+using base::android::ScopedJavaLocalRef;
+
+namespace content {
+
+bool GamepadsReader::RegisterGamepadsReader(JNIEnv* env) {
+        return RegisterNativesImpl(env);
+}
+
+GamepadsReader::GamepadsReader()
+{
+    JNIEnv* env = AttachCurrentThread();
+    CreateJavaObject(env);
+}
+
+GamepadsReader::~GamepadsReader() {
+    CHECK(java_gamepadList_object_.is_null());
+}
+
+GamepadsReader* GamepadsReader::GetInstance() {
+    return Singleton<GamepadsReader>::get();
+}
+
+void GamepadsReader::notifyForGamepadsAccess(bool isaccesspaused) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    Java_GamepadList_notifyForGamepadsAccess(env,
+                                            java_gamepadList_object_.obj(),
+                                            isaccesspaused);
+}
+
+int GamepadsReader::updateGamepadsCount() {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return 0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    ScopedJavaLocalRef<jobject> javaGamepadListObject =
+                        Java_GamepadList_getGamepadList(env,
+                                            java_gamepadList_object_.obj());
+
+    if (javaGamepadListObject.is_null())
+        return 0;

[xwang, 2014/01/14 03:03:22]

What is javaGamepadListObject for? Is that to check whether the gamepads have
been interact with?

[SaurabhK, 2014/01/15 16:57:08]

Yes, it is to check if gamepad device has been interacted with.

[xwang, 2014/01/16 02:36:42]

Why not directly call haveDevicesBeenInteractedWith() to do the check? It's
confusing to use javaGamepadListObject for this.
On 2014/01/15 16:57:08, SaurabhK wrote:

[SaurabhK, 2014/01/28 13:23:09]

Now i am directly calling haveDevicesBeenInteractedWith() in latest patchset

+
+    return (int)Java_GamepadList_getDeviceCount(env,
+                                            java_gamepadList_object_.obj());
+}
+
+bool GamepadsReader::isDeviceConnected(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return false;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    return Java_GamepadList_isDeviceConnected(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index);
+}
+
+std::string GamepadsReader::getDeviceName(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return (std::string)0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+
+    ScopedJavaLocalRef<jstring> str =
+               Java_GamepadList_getDeviceName(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index);
+
+    bool ua_overidden = str.obj() != NULL;
+    std::string override;
+
+    if (override.empty())
+        override += " ";
+
+    if (ua_overidden) {
+        override = base::android::ConvertJavaStringToUTF8(str);
+    }
+
+    return override;
+}
+
+long GamepadsReader::getDeviceTimestamp(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return 0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    return Java_GamepadList_getDeviceTimestamp(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index);
+}
+
+std::vector<float> GamepadsReader::getDeviceAxes(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return (std::vector<float>)0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    std::vector<float> axes;
+    base::android::JavaFloatArrayToFloatVector(
+                env,
+                Java_GamepadList_getDeviceAxes(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index).obj(),
+                &axes);
+    return axes;
+}
+
+std::vector<float> GamepadsReader::getDeviceButtons(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return (std::vector<float>)0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    std::vector<float> buttons;
+    base::android::JavaFloatArrayToFloatVector(
+                env,
+                Java_GamepadList_getDeviceButtons(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index).obj(),
+                &buttons);
+
+    return buttons;
+}
+
+bool GamepadsReader::isGamepadLayoutKnown(int Index) {
+    JNIEnv* env = AttachCurrentThread();
+    if(!env)
+        return 0;
+
+    CHECK(!java_gamepadList_object_.is_null());
+    return Java_GamepadList_isKnownGamepadLayout(env,
+                                            java_gamepadList_object_.obj(),
+                                            Index);
+}
+
+void GamepadsReader::CreateJavaObject(JNIEnv* env) {
+    // Create the Java GamepadsReader object.
+    java_gamepadList_object_.Reset(
+                Java_GamepadList_getInstance(env));
+    CHECK(!java_gamepadList_object_.is_null());
+}
+
+}  // namespace content