Add Performance Statistics to EmulationActivity

This commit adds performance statistics to the emulator that can be toggled in preferences. The layout of `EmulationActivity` was also changed from `ConstraintLayout` to `RelativeLayout` due to poor performance of the former.

app/src/main/cpp/main.cpp

@@ -11,6 +11,8 @@ bool Halt;
 jobject Surface;
 uint FaultCount;
 skyline::GroupMutex JniMtx;
+skyline::u16 fps;
+skyline::u32 frametime;
 
 void signalHandler(int signal) {
     syslog(LOG_ERR, "Halting program due to signal: %s", strsignal(signal));
@@ -74,3 +76,11 @@ extern "C" JNIEXPORT void Java_emu_skyline_EmulationActivity_setSurface(JNIEnv *
         Surface = surface;
     JniMtx.unlock();
 }
+
+extern "C" JNIEXPORT jint Java_emu_skyline_EmulationActivity_getFps(JNIEnv *env, jobject thiz) {
+    return fps;
+}
+
+extern "C" JNIEXPORT jfloat Java_emu_skyline_EmulationActivity_getFrametime(JNIEnv *env, jobject thiz) {
+    return static_cast<float>(frametime) / 100;
+}

app/src/main/cpp/skyline/gpu.cpp

@@ -8,6 +8,8 @@
 
 extern bool Halt;
 extern jobject Surface;
+extern skyline::u16 fps;
+extern skyline::u32 frametime;
 
 namespace skyline::gpu {
     GPU::GPU(const DeviceState &state) : state(state), window(ANativeWindow_fromSurface(state.jvm->GetEnv(), Surface)), vsyncEvent(std::make_shared<kernel::type::KEvent>(state)), bufferEvent(std::make_shared<kernel::type::KEvent>(state)) {
@@ -57,12 +59,16 @@ namespace skyline::gpu {
             vsyncEvent->Signal();
             texture->releaseCallback();
 
-            if (prevTime != 0) {
-                auto now = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
-                state.logger->Error("{} ms, {} FPS", (now - prevTime) / 1000, 1000000 / (now - prevTime));
-            }
+            if (frameTimestamp) {
+                auto now = util::GetTimeNs();
 
-            prevTime = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::steady_clock::now().time_since_epoch()).count();
+                frametime = static_cast<u32>((now - frameTimestamp) / 10000); // frametime / 100 is the real ms value, this is to retain the first two decimals
+                fps = static_cast<u16>(1000000000 / (now - frameTimestamp));
+
+                frameTimestamp = now;
+            } else {
+                frameTimestamp = util::GetTimeNs();
+            }
         }
     }
 }

app/src/main/cpp/skyline/gpu.h

@@ -20,7 +20,7 @@ namespace skyline::gpu {
         ANativeWindow *window; //!< The ANativeWindow to render to
         const DeviceState &state; //!< The state of the device
         bool surfaceUpdate{}; //!< If the surface needs to be updated
-        double prevTime{}; //!< The time passed from the last frame
+        u64 frameTimestamp{}; //!< The timestamp of the last frame being shown
 
       public:
         std::queue<std::shared_ptr<PresentationTexture>> presentationQueue; //!< A queue of all the PresentationTextures to be posted to the display

app/src/main/java/emu/skyline/EmulationActivity.kt

@@ -14,8 +14,9 @@ import android.view.Surface
 import android.view.SurfaceHolder
 import android.view.WindowManager
 import androidx.appcompat.app.AppCompatActivity
+import androidx.preference.PreferenceManager
 import emu.skyline.loader.getRomFormat
-import kotlinx.android.synthetic.main.app_activity.*
+import kotlinx.android.synthetic.main.emu_activity.*
 import java.io.File
 
 class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback {
@@ -78,6 +79,16 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback {
      */
     private external fun setSurface(surface: Surface?)
 
+    /**
+     * This returns the current FPS of the application
+     */
+    private external fun getFps(): Int
+
+    /**
+     * This returns the current frame-time of the application
+     */
+    private external fun getFrametime(): Float
+
     /**
      * This executes the specified ROM, [preferenceFd] and [logFd] are assumed to be valid beforehand
      *
@@ -101,12 +112,14 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback {
     }
 
     /**
-     * This sets up [preferenceFd] and [logFd] then calls [executeApplication] for executing the application
+     * This makes the window fullscreen then sets up [preferenceFd] and [logFd], sets up the performance statistics and finally calls [executeApplication] for executing the application
      */
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        setContentView(R.layout.app_activity)
+        setContentView(R.layout.emu_activity)
+
+        window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN)
 
         val preference = File("${applicationInfo.dataDir}/shared_prefs/${applicationInfo.packageName}_preferences.xml")
         preferenceFd = ParcelFileDescriptor.open(preference, ParcelFileDescriptor.MODE_READ_WRITE)
@@ -114,9 +127,21 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback {
         val log = File("${applicationInfo.dataDir}/skyline.log")
         logFd = ParcelFileDescriptor.open(log, ParcelFileDescriptor.MODE_CREATE or ParcelFileDescriptor.MODE_READ_WRITE)
 
-        window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN)
         game_view.holder.addCallback(this)
 
+        val sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this)
+
+        if (sharedPreferences.getBoolean("perf_stats", false)) {
+            lateinit var perfRunnable: Runnable
+
+            perfRunnable = Runnable {
+                perf_stats.text = "${getFps()} FPS\n${getFrametime()}ms"
+                perf_stats.postDelayed(perfRunnable, 250)
+            }
+
+            perf_stats.postDelayed(perfRunnable, 250)
+        }
+
         executeApplication(intent.data!!)
     }
 

app/src/main/res/layout/app_activity.xml

@@ -1,18 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:app="http://schemas.android.com/apk/res-auto"
-        xmlns:tools="http://schemas.android.com/tools"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        tools:context=".EmulationActivity">
-
-    <SurfaceView
-            android:id="@+id/game_view"
-            android:layout_width="0dp"
-            android:layout_height="0dp"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintTop_toTopOf="parent" />
-
-</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/layout/emu_activity.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".EmulationActivity">
+
+    <SurfaceView
+            android:id="@+id/game_view"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_alignParentStart="true"
+            android:layout_alignParentTop="true" />
+
+    <TextView
+            android:id="@+id/perf_stats"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignParentStart="true"
+            android:layout_alignParentTop="true"
+            android:layout_marginStart="5dp"
+            android:layout_marginTop="5dp"
+            android:textColor="#5fffffff" />
+
+</RelativeLayout>

app/src/main/res/values/strings.xml

@@ -32,7 +32,7 @@
     <string name="log_level">Log Level</string>
     <string name="log_compact">Compact Logs</string>
     <string name="log_compact_desc_on">Logs will be displayed in a compact form factor</string>
-    <string name="log_compact_desc_off">The logs will be displayed in a verbose form factor</string>
+    <string name="log_compact_desc_off">Logs will be displayed in a verbose form factor</string>
     <string name="system">System</string>
     <string name="use_docked">Use Docked Mode</string>
     <string name="handheld_enabled">The system will emulate being in handheld mode</string>
@@ -59,4 +59,7 @@
     <string name="ktstd_description">We use Kotlin Standard Library for accessing convenience functions in Kotlin (Apache License 2.0)</string>
     <string name="mtico">Material Design Icons</string>
     <string name="mtico_description">We use Material Design Icons to have consistent iconography throughout the application</string>
+    <string name="perf_stats">Show Performance Statistics</string>
+    <string name="perf_stats_desc_off">Performance Statistics will not be shown</string>
+    <string name="perf_stats_desc_on">Performance Statistics will be shown in the top-left corner</string>
 </resources>

app/src/main/res/xml/preferences.xml

@@ -43,6 +43,12 @@
                 android:summaryOn="@string/select_action_desc_on"
                 app:key="select_action"
                 app:title="@string/select_action" />
+        <CheckBoxPreference
+                android:defaultValue="false"
+                android:summaryOff="@string/perf_stats_desc_off"
+                android:summaryOn="@string/perf_stats_desc_on"
+                app:key="perf_stats"
+                app:title="@string/perf_stats" />
         <ListPreference
                 android:defaultValue="2"
                 android:entries="@array/log_level"