[SilkFX] The very first version of lut demo app

Relnote: Now only support to play with Lut on the image. We provide the
pre-defined Lut, and users can check the button to see the results.

Bug: 391680040
Test: play with SilkFX
Flag: EXEMPT demo app development

Change-Id: I0f82126c1fd7cbb474e6c619709de641dfa636b5

5 files changed, 275 insertions, 1 deletions

diff --git a/tests/graphics/SilkFX/AndroidManifest.xml b/tests/graphics/SilkFX/AndroidManifest.xml
index c293589bdbaf..be637567b669 100644
--- a/tests/graphics/SilkFX/AndroidManifest.xml
+++ b/tests/graphics/SilkFX/AndroidManifest.xml
@@ -70,5 +70,10 @@
             </intent-filter>
         </activity>
 
+        <activity android:name=".hdr.LutTestActivity"
+            android:theme="@style/Theme.LutTestTheme"
+            android:label="Lut Test Examples"
+            android:exported="true"/>
+
     </application>
 </manifest>
diff --git a/tests/graphics/SilkFX/res/layout/lut_test.xml b/tests/graphics/SilkFX/res/layout/lut_test.xml
new file mode 100644
index 000000000000..f550f397cfa5
--- /dev/null
+++ b/tests/graphics/SilkFX/res/layout/lut_test.xml
@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2025 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <SurfaceView
+        android:id="@+id/surfaceView"
+        android:layout_width="match_parent"
+        android:layout_height="300dp"
+        android:layout_weight="1"
+        android:layout_marginTop="16dp" />
+
+    <RadioGroup android:id="@+id/lut_option"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:orientation="horizontal">
+
+        <RadioButton android:id="@+id/lut_1d"
+                      android:layout_width="wrap_content"
+                      android:layout_weight="1"
+                      android:layout_height="wrap_content"
+                      android:text="1D Lut" />
+
+        <RadioButton android:id="@+id/lut_3d"
+                      android:layout_width="wrap_content"
+                      android:layout_weight="1"
+                      android:layout_height="wrap_content"
+                      android:text="3D Lut" />
+
+        <RadioButton android:id="@+id/no_lut"
+                      android:layout_width="wrap_content"
+                      android:layout_weight="1"
+                      android:layout_height="wrap_content"
+                      android:text="Original image" />
+    </RadioGroup>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/tests/graphics/SilkFX/res/values/style.xml b/tests/graphics/SilkFX/res/values/style.xml
index 75506978024b..d162bd0926d3 100644
--- a/tests/graphics/SilkFX/res/values/style.xml
+++ b/tests/graphics/SilkFX/res/values/style.xml
@@ -24,6 +24,13 @@
         <item name="buttonStyle">@style/AppTheme.Button</item>
         <item name="colorAccent">#bbffffff</item>
     </style>
+    <style name="Theme.LutTestTheme" parent="Theme.AppCompat.Dialog">
+        <item name="android:windowBlurBehindEnabled">true</item>
+        <item name="android:backgroundDimEnabled">false</item>
+        <item name="android:windowElevation">0dp</item>
+        <item name="buttonStyle">@style/AppTheme.Button</item>
+        <item name="colorAccent">#bbffffff</item>
+    </style>
     <style name="AppTheme.Button" parent="Widget.AppCompat.Button">
         <item name="android:textColor">#ffffffff</item>
     </style>
diff --git a/tests/graphics/SilkFX/src/com/android/test/silkfx/Main.kt b/tests/graphics/SilkFX/src/com/android/test/silkfx/Main.kt
index ad7cde44bb35..be499b6ce26d 100644
--- a/tests/graphics/SilkFX/src/com/android/test/silkfx/Main.kt
+++ b/tests/graphics/SilkFX/src/com/android/test/silkfx/Main.kt
@@ -30,6 +30,7 @@ import com.android.test.silkfx.app.EXTRA_COMMON_CONTROLS
 import com.android.test.silkfx.app.EXTRA_LAYOUT
 import com.android.test.silkfx.app.EXTRA_TITLE
 import com.android.test.silkfx.hdr.GlowActivity
+import com.android.test.silkfx.hdr.LutTestActivity
 import com.android.test.silkfx.materials.GlassActivity
 import com.android.test.silkfx.materials.BackgroundBlurActivity
 import kotlin.reflect.KClass
@@ -57,7 +58,8 @@ private val AllDemos = listOf(
                 Demo("Gainmap Image", R.layout.gainmap_image),
                 Demo("Gainmap Decode Test", R.layout.gainmap_decode_test, commonControls = false),
                 Demo("Gainmap Transform Test", R.layout.gainmap_transform_test,
-                        commonControls = false)
+                        commonControls = false),
+                Demo("Lut Test", LutTestActivity::class)
         )),
         DemoGroup("Materials", listOf(
                 Demo("Glass", GlassActivity::class),
diff --git a/tests/graphics/SilkFX/src/com/android/test/silkfx/hdr/LutTestActivity.kt b/tests/graphics/SilkFX/src/com/android/test/silkfx/hdr/LutTestActivity.kt
new file mode 100644
index 000000000000..319f58cbfdcc
--- /dev/null
+++ b/tests/graphics/SilkFX/src/com/android/test/silkfx/hdr/LutTestActivity.kt
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.test.silkfx.hdr
+
+import android.graphics.Bitmap
+import android.graphics.ColorSpace
+import android.graphics.ImageDecoder
+import android.graphics.Matrix
+import android.graphics.HardwareBufferRenderer
+import android.graphics.RenderNode
+import android.hardware.DisplayLuts
+import android.hardware.HardwareBuffer
+import android.hardware.LutProperties
+import android.os.Bundle
+import android.view.SurfaceControl
+import android.view.SurfaceView
+import android.view.SurfaceHolder
+import androidx.appcompat.app.AppCompatActivity
+import android.widget.RadioGroup
+import android.util.Log
+import com.android.test.silkfx.R
+import java.io.IOException
+import java.util.concurrent.CountDownLatch
+import java.util.concurrent.Executors
+
+class LutTestActivity : AppCompatActivity() {
+
+    private lateinit var surfaceView: SurfaceView
+    private var surfaceControl: SurfaceControl? = null
+    private var currentBitmap: Bitmap? = null
+    private var renderNode = RenderNode("LutRenderNode")
+    private var currentLutType: Int = R.id.no_lut // Store current LUT type
+    private val TAG = "LutTestActivity"
+    private val renderExecutor = Executors.newSingleThreadExecutor()
+
+    /** Called when the activity is first created. */
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.lut_test)
+
+        surfaceView = findViewById(R.id.surfaceView)
+
+        surfaceView.holder.addCallback(object : SurfaceHolder.Callback {
+            override fun surfaceCreated(holder: SurfaceHolder) {
+                createChildSurfaceControl()
+                loadImage("gainmaps/sunflower.jpg", holder)
+                currentBitmap?.let {
+                    createAndRenderHardwareBuffer(holder, it, getCurrentLut())
+                }
+            }
+
+            override fun surfaceChanged(
+                holder: SurfaceHolder,
+                format: Int,
+                width: Int,
+                height: Int
+            ) {
+            }
+
+            override fun surfaceDestroyed(holder: SurfaceHolder) {
+            }
+        })
+
+        var lutOption = findViewById<RadioGroup>(R.id.lut_option)
+        // handle RadioGroup selection changes
+        lutOption.setOnCheckedChangeListener(
+            RadioGroup.OnCheckedChangeListener { _, id ->
+                currentLutType = id
+                if (surfaceControl != null) {
+                    applyCurrentLut()
+                }
+            }
+        )
+    }
+
+    private fun applyCurrentLut() {
+        when (currentLutType) {
+            R.id.lut_1d -> {
+                currentBitmap?.let {
+                    createAndRenderHardwareBuffer(surfaceView.holder, it, get1DLut())
+                }
+            }
+            R.id.lut_3d -> {
+                currentBitmap?.let {
+                    createAndRenderHardwareBuffer(surfaceView.holder, it, get3DLut())
+                }
+            }
+            R.id.no_lut -> {
+                currentBitmap?.let {
+                    createAndRenderHardwareBuffer(surfaceView.holder, it, null)
+                }
+            }
+        }
+    }
+
+    private fun getCurrentLut(): DisplayLuts {
+        when (currentLutType) {
+            R.id.lut_1d -> return get1DLut()
+            R.id.lut_3d -> return get3DLut()
+            R.id.no_lut -> return DisplayLuts()
+        }
+        return DisplayLuts()
+    }
+
+    private fun get3DLut(): DisplayLuts {
+        var luts = DisplayLuts()
+        val entry = DisplayLuts.Entry(
+            floatArrayOf(0.5f, 0.5f, 0.5f, 0.5f, 0.5f, 0.5f, 0.5f, 0.5f,
+                         0f, 0f, 0f, 0f, 0f, 0f, 0f, 0f,
+                         1f, 1f, 1f, 1f, 1f, 1f, 1f, 1f),
+            LutProperties.THREE_DIMENSION,
+            LutProperties.SAMPLING_KEY_RGB
+        )
+        luts.set(entry)
+        return luts
+    }
+
+    private fun get1DLut(): DisplayLuts {
+        var luts = DisplayLuts()
+        val entry = DisplayLuts.Entry(
+            floatArrayOf(0.1f, 0.1f, 0.1f, 0.1f, 0.1f, 0.1f, 0.1f, 0.1f),
+            LutProperties.ONE_DIMENSION,
+            LutProperties.SAMPLING_KEY_RGB
+        )
+        luts.set(entry)
+        return luts
+    }
+
+    private fun createChildSurfaceControl() {
+        surfaceView.surfaceControl?.let { parentSC ->
+            surfaceControl = SurfaceControl.Builder()
+                .setParent(parentSC)
+                .setBufferSize(surfaceView.width, surfaceView.height)
+                .setName("LutTestSurfaceControl")
+                .setHidden(false)
+                .build()
+        }
+    }
+
+    private fun loadImage(assetPath: String, holder: SurfaceHolder) {
+        try {
+            val source = ImageDecoder.createSource(assets, assetPath)
+            currentBitmap = ImageDecoder.decodeBitmap(source) { decoder, info, source ->
+                decoder.allocator = ImageDecoder.ALLOCATOR_SOFTWARE
+            }
+        } catch (e: IOException) {
+            Log.e(TAG, "Error loading image: ${e.message}")
+            e.printStackTrace()
+        }
+    }
+
+    private fun createAndRenderHardwareBuffer(holder: SurfaceHolder, bitmap: Bitmap, luts: DisplayLuts?) {
+        val imageWidth = bitmap.width
+        val imageHeight = bitmap.height
+
+        val buffer = HardwareBuffer.create(
+            imageWidth,
+            imageHeight,
+            HardwareBuffer.RGBA_8888,
+            1, // layers
+            HardwareBuffer.USAGE_GPU_COLOR_OUTPUT or HardwareBuffer.USAGE_GPU_SAMPLED_IMAGE
+        )
+        val renderer = HardwareBufferRenderer(buffer)
+        renderNode.setPosition(0, 0, buffer.width, buffer.height)
+        renderer.setContentRoot(renderNode)
+
+        val canvas = renderNode.beginRecording()
+
+        // calculate the scale to match the screen
+        val surfaceWidth = holder.surfaceFrame.width()
+        val surfaceHeight = holder.surfaceFrame.height()
+
+        val scaleX = surfaceWidth.toFloat() / imageWidth.toFloat()
+        val scaleY = surfaceHeight.toFloat() / imageHeight.toFloat()
+        val scale = minOf(scaleX, scaleY)
+
+        val matrix = Matrix().apply{ postScale(scale, scale) }
+        canvas.drawBitmap(bitmap, matrix, null)
+        renderNode.endRecording()
+
+        val colorSpace = ColorSpace.get(ColorSpace.Named.BT2020_HLG)
+        val latch = CountDownLatch(1)
+        renderer.obtainRenderRequest().setColorSpace(colorSpace).draw(renderExecutor) { renderResult ->
+            surfaceControl?.let {
+                SurfaceControl.Transaction().setBuffer(it, buffer, renderResult.fence).setLuts(it, luts).apply()
+            }
+            latch.countDown()
+        }
+        latch.await() // Wait for the fence to complete.
+        buffer.close()
+    }
+}
\ No newline at end of file