Implement Ambient mode (#44)

app/build.gradle

@@ -180,6 +180,7 @@ dependencies {
     implementation "com.google.dagger:hilt-android:$hilt_version"
     kapt "com.google.dagger:hilt-compiler:$hilt_version"
     implementation 'com.google.android.flexbox:flexbox:3.0.0'
+    implementation 'androidx.palette:palette-ktx:1.0.0'
 
     /* Kotlin */
     implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"

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

@@ -31,9 +31,11 @@ import android.util.Log
 import android.util.Rational
 import android.util.TypedValue
 import android.view.*
+import android.view.ViewTreeObserver
 import android.widget.Toast
 import android.widget.PopupMenu
 import android.widget.TextView
+import android.animation.ObjectAnimator
 import androidx.activity.OnBackPressedCallback
 import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
@@ -71,6 +73,7 @@ import emu.skyline.settings.SettingsActivity
 import emu.skyline.utils.ByteBufferSerializable
 import emu.skyline.utils.GpuDriverHelper
 import emu.skyline.utils.serializable
+import emu.skyline.utils.AmbientHelper
 import emu.skyline.input.onscreen.OnScreenEditActivity
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
@@ -80,7 +83,7 @@ import java.nio.ByteOrder
 import java.util.concurrent.FutureTask
 import javax.inject.Inject
 import kotlin.math.abs
-
+import kotlinx.coroutines.*
 
 private const val ActionPause = "${BuildConfig.APPLICATION_ID}.ACTION_EMULATOR_PAUSE"
 private const val ActionMute = "${BuildConfig.APPLICATION_ID}.ACTION_EMULATOR_MUTE"
@@ -207,6 +210,9 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback, View.OnTo
 
     private external fun setAudioSink(sink: String)
 
+    private var ambientJob: Job? = null
+    private lateinit var ambientHelper: AmbientHelper
+
     /**
      * @see [InputHandler.initializeControllers]
      */
@@ -502,6 +508,18 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback, View.OnTo
         }
         setInsets()
         executeApplication(intent!!)
+        if (emulationSettings.enableAmbientMode) {
+            binding.gameView.viewTreeObserver.addOnPreDrawListener(object : ViewTreeObserver.OnPreDrawListener {
+                override fun onPreDraw(): Boolean {
+                    if (binding.gameView.width > 0 && binding.gameView.height > 0) {
+                        ambientHelper = AmbientHelper(binding.gameView)
+                        startAmbientEffectUpdates()
+                        binding.gameView.viewTreeObserver.removeOnPreDrawListener(this)
+                    }
+                    return true
+                }
+            })
+        }    
     }
 
     private fun setInsets() {
@@ -522,6 +540,36 @@ class EmulationActivity : AppCompatActivity(), SurfaceHolder.Callback, View.OnTo
         }
     }
 
+    private fun startAmbientEffectUpdates() {
+        ambientJob = CoroutineScope(Dispatchers.Main).launch {
+            var previousColor = Color.BLACK
+            while (isActive) {
+                ambientHelper.captureAmbientEffect(object : AmbientHelper.AmbientCallback {
+                    override fun onColorsExtracted(vibrantColor: Int, mutedColor: Int, dominantColor: Int) {
+                        val animator = ObjectAnimator.ofArgb(
+                            binding.gameViewContainer,
+                            "backgroundColor",
+                            previousColor,
+                            dominantColor
+                        )
+                        animator.duration = 300 // Smooth transition duration
+                        animator.start()
+                        previousColor = dominantColor
+                    }
+
+                    override fun onError(error: String) {
+                        Log.e("AmbientHelper", error)
+                    }
+                })
+                delay(50)
+            }
+        }
+    }
+
+    private fun stopAmbientEffectUpdates() {
+        ambientJob?.cancel()
+    }
+
     @SuppressWarnings("WeakerAccess")
     fun pauseEmulator() {
         if (isEmulatorPaused) return

app/src/main/java/emu/skyline/settings/EmulationSettings.kt

@@ -43,6 +43,7 @@ class EmulationSettings private constructor(context : Context, prefName : String
     var respectDisplayCutout by sharedPreferences(context, false, prefName = prefName)
     var enableFoldableLayout by sharedPreferences(context, false, prefName = prefName)
     var showPauseButton by sharedPreferences(context, false, prefName = prefName)
+    var enableAmbientMode by sharedPreferences(context, false, prefName = prefName)
 
     // CPU
     var cpuBackend by sharedPreferences(context, 0, prefName = prefName)

app/src/main/java/emu/skyline/utils/AmbientHelper.kt

@@ -0,0 +1,70 @@
+
+package emu.skyline.utils
+
+import android.graphics.Bitmap
+import android.graphics.Color
+import android.graphics.Rect
+import android.os.Handler
+import android.os.Looper
+import android.view.SurfaceView
+import android.view.PixelCopy
+import androidx.palette.graphics.Palette
+
+class AmbientHelper(private val surfaceView: SurfaceView) {
+
+    interface AmbientCallback {
+        fun onColorsExtracted(vibrantColor: Int, mutedColor: Int, dominantColor: Int)
+        fun onError(error: String)
+    }
+
+    /**
+     * Starts capturing and processing the SurfaceView for ambient effects.
+     */
+    fun captureAmbientEffect(callback: AmbientCallback) {
+        val bitmap = Bitmap.createBitmap(
+            surfaceView.width,
+            surfaceView.height,
+            Bitmap.Config.ARGB_8888
+        )
+        val location = IntArray(2)
+        surfaceView.getLocationInWindow(location)
+
+        val rect = Rect(
+            location[0],
+            location[1],
+            location[0] + surfaceView.width,
+            location[1] + surfaceView.height
+        )
+
+        // Use PixelCopy to capture the SurfaceView contents
+        PixelCopy.request(
+            surfaceView,
+            bitmap,
+            { result ->
+                if (result == PixelCopy.SUCCESS) {
+                    extractColors(bitmap, callback)
+                } else {
+                    callback.onError("Failed to capture surface content. PixelCopy result: $result")
+                }
+            },
+            Handler(Looper.getMainLooper())
+        )
+    }
+
+    /**
+     * Extracts colors from a Bitmap using the Palette library.
+     */
+    private fun extractColors(bitmap: Bitmap, callback: AmbientCallback) {
+        Palette.from(bitmap).generate { palette ->
+            if (palette != null) {
+                val vibrantColor = palette.getVibrantColor(Color.BLACK)
+                val mutedColor = palette.getMutedColor(Color.GRAY)
+                val dominantColor = palette.getDominantColor(Color.DKGRAY)
+
+                callback.onColorsExtracted(vibrantColor, mutedColor, dominantColor)
+            } else {
+                callback.onError("Failed to generate palette from bitmap.")
+            }
+        }
+    }
+}

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

@@ -127,6 +127,8 @@
     <string name="show_pause_button">Show Pause Button</string>
     <string name="show_pause_button_disabled">The pause button won\'t be displayed</string>
     <string name="show_pause_button_enabled">The pause button will be displayed</string>
+    <string name="enable_ambient_mode">Enable Ambient Mode</string>
+    <string name="enable_ambient_mode_desc">Ambient effect will be applied</string>
     <!-- Settings - Audio -->
     <string name="audio">Audio</string>
     <string name="audio_output_engine">Output engine</string>

app/src/main/res/xml/emulation_preferences.xml

@@ -90,6 +90,11 @@
             android:summaryOn="@string/show_pause_button_enabled"
             android:key="show_pause_button"
             android:title="@string/show_pause_button" />
+        <SwitchPreferenceCompat
+            android:defaultValue="false"
+            android:summary="@string/enable_ambient_mode_desc"
+            android:key="enable_ambient_mode"
+            android:title="@string/enable_ambient_mode" />
     </PreferenceCategory>
     <PreferenceCategory
         android:key="category_audio"