...

app/src/main/cpp/CMakeLists.txt

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.10.2)
+project("native_renderer")
+
+add_library(native-renderer SHARED native_renderer.cpp)
+
+find_library(log-lib log)
+
+target_link_libraries(native-renderer ${log-lib} android)

app/src/main/cpp/native_renderer.cpp

@@ -0,0 +1,82 @@
+#include <jni.h>
+#include <android/native_window_jni.h>
+#include <android/native_window.h>
+#include <android/log.h>
+
+#define LOG_TAG "NativeRenderer"
+#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
+#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
+
+static ANativeWindow* window = nullptr;
+
+extern "C" JNIEXPORT void JNICALL
+Java_bums_lunatic_launcher_wall_NativeRenderer_nativeInit(JNIEnv* env, jobject, jobject surface) {
+    if (window != nullptr) {
+        ANativeWindow_release(window);
+        window = nullptr;
+    }
+    window = ANativeWindow_fromSurface(env, surface);
+    LOGI("Native window initialized");
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_bums_lunatic_launcher_wall_NativeRenderer_nativeRender(
+        JNIEnv* env, jobject, jintArray pixels, jint width, jint height,
+        jfloat offsetX, jfloat offsetY, jfloat fadeAlpha) {
+
+    if (!window) return;
+
+    ANativeWindow_Buffer buffer;
+    if (ANativeWindow_lock(window, &buffer, nullptr) < 0) {
+        LOGE("Failed to lock native window");
+        return;
+    }
+
+    jint* srcPixels = env->GetIntArrayElements(pixels, nullptr);
+    if (!srcPixels) {
+        ANativeWindow_unlockAndPost(window);
+        return;
+    }
+
+    uint32_t* dstPixels = (uint32_t*)buffer.bits;
+    int stride = buffer.stride;
+
+    int offsetXInt = static_cast<int>(offsetX);
+    int offsetYInt = static_cast<int>(offsetY);
+
+    for (int y = 0; y < buffer.height; y++) {
+        int srcY = y - offsetYInt;
+        if (srcY < 0 || srcY >= height) continue;
+
+        for (int x = 0; x < buffer.width; x++) {
+            int srcX = x - offsetXInt;
+            if (srcX < 0 || srcX >= width) continue;
+
+            uint32_t pixel = srcPixels[srcY * width + srcX];
+
+            uint8_t alpha = static_cast<uint8_t>(fadeAlpha * 255);
+            uint8_t r = (pixel >> 16) & 0xFF;
+            uint8_t g = (pixel >> 8) & 0xFF;
+            uint8_t b = pixel & 0xFF;
+
+            r = (r * alpha) / 255;
+            g = (g * alpha) / 255;
+            b = (b * alpha) / 255;
+
+            dstPixels[y * stride + x] = (0xFF << 24) | (r << 16) | (g << 8) | b;
+        }
+    }
+
+    env->ReleaseIntArrayElements(pixels, srcPixels, JNI_ABORT);
+
+    ANativeWindow_unlockAndPost(window);
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_bums_lunatic_launcher_wall_NativeRenderer_nativeDestroy(JNIEnv*, jobject) {
+    if (window) {
+        ANativeWindow_release(window);
+        window = nullptr;
+        LOGI("Native window released");
+    }
+}