Use TextureView's and animated transitions

[kiryldz]

Summary

Migrate camera previews from SurfaceView to TextureView and make the dual-preview resize animation smooth on both OpenGL and Vulkan. Also fixes several latent bugs in the Vulkan swapchain teardown/recreate path
that were producing visible corruption on resize.

UI / Compose

• CameraPreviewView now uses TextureView (composited in the view hierarchy) instead of SurfaceView, so the preview's bounds animate in lockstep with the surrounding layout — no more hard-edge jumps against the
  rest of the UI.
• Click handlers animate weight to exactly 0.0f (previously 0.1f); Modifier.weight is coerced to a sub-pixel MIN_WEIGHT floor so the spec's "strictly positive" requirement is satisfied while the visible Box
  rounds to 0 px before being removed by finishedListener. No more 10 % sliver → "gone" pop.
• Resize tween bumped from 0 ms to 1000 ms.

CoreEngine (Kotlin) — refit API

• Implements TextureView.SurfaceTextureListener (replaces SurfaceHolder.Callback).
• New fun refit(weight: Float): Boolean that the UI calls from a SideEffect on every animation frame. Internally filters by threshold crossings of REFIT_THRESHOLDS = floatArrayOf(0.1f, 0.5f) plus endpoint
  settlement at 0.0f/1.0f, and forwards only those events through a new nativeRefit() JNI binding.

BaseRenderer

• New public refit() entry point; new virtual onRefit(w, h) (default no-op) for renderers that defer heavy size work to UI-driven checkpoints.
• updateWindowSize is now coalesced via atomics (pendingViewportWidth/Height + a resizeTaskScheduled CAS) — multiple surfaceTextureSizeChanged callbacks collapse into a single render-thread task reading the
  latest dimensions.
• onWindowSizeUpdated retains its per-tick contract: OpenGL keeps doing glViewport every tick, Vulkan overrides it as a no-op.

VulkanRenderer — swapchain teardown/recreate fixes

• New recreateSwapChain(width, height) helper used by both onRefit and the VK_ERROR_OUT_OF_DATE_KHR recovery in renderImpl. It:
  • Uses vkQueueWaitIdle instead of vkDeviceWaitIdle.
  • Passes the old swapchain via VkSwapchainCreateInfoKHR.oldSwapchain so the driver can reuse internal allocations (no more from-scratch reallocation per resize).
  • Re-records command buffers after rebuild — fixes the corruption/flicker that was happening because submits kept referencing destroyed framebuffers.
  • Reallocates the cmdBuffer[] storage when the new swapchain image count differs.
• cleanupSwapChain now delete[]s framebuffers/displayViews/displayImages (previously leaked); cleanup() also delete[]s cmdBuffer.
• renderImpl's recovery now handles VK_ERROR_OUT_OF_DATE_KHR only; VK_SUBOPTIMAL_KHR no longer triggers an early-return that left the acquire semaphore signaled.

[Copilot]

Pull request overview

Migrate camera previews from SurfaceView to TextureView to enable smooth layout-driven preview resizing, while adding a UI-driven “refit” mechanism that lets renderers (especially Vulkan) rebuild/adjust at key animation frames and fixes swapchain recreate/teardown issues that caused resize corruption.

Changes:

• Switch preview surface plumbing from SurfaceHolder.Callback/SurfaceView to TextureView.SurfaceTextureListener/TextureView.
• Add a UI-driven refit() path from Compose → Kotlin → JNI → native renderer, and coalesce per-tick size updates.
• Improve Vulkan swapchain recreation (reuse old swapchain, re-record command buffers, fix teardown leaks) and tighten VK_ERROR_OUT_OF_DATE_KHR recovery behavior.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
app/src/main/native/cpp/vulkan_renderer.hpp	Add onRefit() hook usage and declare swapchain recreation helpers / signature changes.
app/src/main/native/cpp/vulkan_renderer.cpp	Implement swapchain recreation improvements and swapchain cleanup fixes; adjust acquire error handling.
app/src/main/native/cpp/core_engine.hpp	Register new JNI entry point nativeRefit.
app/src/main/native/cpp/core_engine.cpp	Implement nativeRefit() forwarding into the renderer.
app/src/main/native/cpp/base_renderer.hpp	Add refit() API and atomics for coalescing resize tasks.
app/src/main/native/cpp/base_renderer.cpp	Coalesce window-size updates via atomics and add render-thread refit() scheduling.
app/src/main/java/com/dz/camerafast/CoreEngine.kt	Switch to TextureView.SurfaceTextureListener and add threshold-filtered refit(weight) behavior.
app/src/main/java/com/dz/camerafast/CameraPreviewView.kt	Replace SurfaceView preview with TextureView.
app/src/main/java/com/dz/camerafast/CameraActivity.kt	Smooth resize animation, weight-to-zero behavior, and drive refit() via SideEffect.
app/src/main/java/com/dz/camerafast/Camera2.kt	Null-safe Image handling around acquireLatestImage() and close().

Comments suppressed due to low confidence (1)

app/src/main/native/cpp/base_renderer.cpp:49

• The scheduled task loads width and height from two independent atomics. Even with stronger memory ordering, it can observe a mixed pair (new width with old height, or vice versa) if a producer updates between the two loads, which can briefly produce incorrect aspect ratios/MVP. If you need consistency, consider packing (width,height) into a single std::atomic<uint64_t> (or use a sequence counter) and reading it atomically in one load.

    resizeTaskScheduled.store(false, std::memory_order_release);
    const int width = pendingViewportWidth.load(std::memory_order_relaxed);
    const int height = pendingViewportHeight.load(std::memory_order_relaxed);
    if (viewportWidth != width || viewportHeight != height) {

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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 6 comments.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

app/src/main/native/cpp/core_engine.cpp:108

• nativeDestroy() currently just resets renderer without ensuring the render thread runs onWindowDestroyed()/cleanup, and without releasing aNativeWindow / gpuBuffer. If destroy happens before the Java-side surface teardown callback, Vulkan/GL resources (and the fallback AHardwareBuffer) can leak. Consider calling renderer->resetWindow() (or otherwise invoking cleanup) when aNativeWindow is set, releasing aNativeWindow, and releasing/freeing gpuBuffer before renderer.reset().

void CoreEngine::nativeDestroy(JNIEnv &env) {
  LOGI("Core engine destroy started");
  renderer.reset();
  LOGI("Core engine destroy passed");

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[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

app/src/main/native/cpp/core_engine.cpp:81

• This early-return reduces the chance of dereferencing a null renderer, but it does not make the code thread-safe: reading renderer on the camera worker thread while nativeDestroy() resets it on another thread is still a C++ data race (UB). Consider guarding all accesses to renderer with the same mutex (including nativeSetSurface, nativeUpdateWindowSize, nativeSendCameraFrame, and nativeDestroy) or restructuring shutdown so the camera thread is joined before renderer.reset() happens.

/** called from worker thread **/
void CoreEngine::nativeSendCameraFrame(JNIEnv &env, const jni::Object<HardwareBuffer> &buffer,
                                       jni::jint rotationDegrees, jni::jboolean backCamera) {
  // Camera worker can fire after nativeDestroy() has reset the renderer. Skip the frame rather
  // than deref a moved-from unique_ptr — this is not race-free against a concurrent destroy
  // (would need a mutex for that) but covers the common ordering where destroy completes first.
  if (!renderer) {
    return;
  }

app/src/main/native/cpp/core_engine.cpp:120

• nativeDestroy() resets the renderer but never releases aNativeWindow (and any other native resources owned by CoreEngine). If destroy() is called before onSurfaceTextureDestroyed/nativeSetSurface(null, …) runs, the ANativeWindow_fromSurface strong ref can leak for the remainder of the process. Consider explicitly calling renderer->resetWindow() (if non-null) and ANativeWindow_release(aNativeWindow) / aNativeWindow = nullptr as part of destroy (and similarly releasing gpuBuffer if owned).

void CoreEngine::nativeDestroy(JNIEnv &env) {
  LOGI("Core engine destroy started");
  renderer.reset();
  LOGI("Core engine destroy passed");

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Comments suppressed due to low confidence (1)

app/src/main/java/com/dz/camerafast/CoreEngine.kt:96

• CoreEngine.destroy() currently only calls nativeDestroy(). If this is invoked before TextureView teardown, the renderer can be destroyed without ever receiving nativeSetSurface(null)/resetWindow, and Surface/TextureView callbacks may still fire afterward against a destroyed native peer. Consider making destroy() proactively detach the SurfaceTextureListener, release the held Surface, and call nativeSetSurface(null, 0, 0) before nativeDestroy so native render resources are deterministically torn down and no further callbacks can reach JNI.

  fun destroy() {
    nativeDestroy()
  }

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.