LibGfx+LibWebView+UI: Store Gfx::Bitmap in RefPtr to const

Author: https://github.com/ADKaster
Commit: 91b549f797
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4362
Reviewed-by: https://github.com/AtkinsSJ
Reviewed-by: https://github.com/Hendiadyoin1

Libraries/LibGfx/ImageFormats/WebPWriterLossless.cpp

@@ -333,7 +333,7 @@ static ARGB32 sub_argb32(ARGB32 a, ARGB32 b)
         .value();
 }
 
-static ErrorOr<NonnullRefPtr<Bitmap>> maybe_write_color_indexing_transform(LittleEndianOutputBitStream& bit_stream, NonnullRefPtr<Bitmap> bitmap, IsOpaque& is_fully_opaque)
+static ErrorOr<NonnullRefPtr<Bitmap const>> maybe_write_color_indexing_transform(LittleEndianOutputBitStream& bit_stream, NonnullRefPtr<Bitmap const> bitmap, IsOpaque& is_fully_opaque)
 {
     // https://developers.google.com/speed/webp/docs/webp_lossless_bitstream_specification#44_color_indexing_transform
     unsigned color_table_size = 0;
@@ -427,7 +427,7 @@ static ErrorOr<NonnullRefPtr<Bitmap>> maybe_write_color_indexing_transform(Littl
     return new_bitmap;
 }
 
-static ErrorOr<void> write_VP8L_image_data(Stream& stream, NonnullRefPtr<Bitmap> bitmap, VP8LEncoderOptions const& options, IsOpaque& is_fully_opaque)
+static ErrorOr<void> write_VP8L_image_data(Stream& stream, NonnullRefPtr<Bitmap const> bitmap, VP8LEncoderOptions const& options, IsOpaque& is_fully_opaque)
 {
     LittleEndianOutputBitStream bit_stream { MaybeOwned<Stream>(stream) };
 

Libraries/LibWebView/ViewImplementation.h

@@ -267,7 +267,7 @@ protected:
     struct SharedBitmap {
         i32 id { -1 };
         Web::DevicePixelSize last_painted_size;
-        RefPtr<Gfx::Bitmap> bitmap;
+        RefPtr<Gfx::Bitmap const> bitmap;
     };
 
     struct ClientState {
@@ -289,7 +289,7 @@ protected:
 
     RefPtr<Core::Timer> m_backing_store_shrink_timer;
 
-    RefPtr<Gfx::Bitmap> m_backup_bitmap;
+    RefPtr<Gfx::Bitmap const> m_backup_bitmap;
     Web::DevicePixelSize m_backup_bitmap_size;
 
     size_t m_crash_count = 0;

UI/AppKit/Interface/LadybirdWebViewBridge.cpp

@@ -95,7 +95,7 @@ void WebViewBridge::enqueue_input_event(Web::KeyEvent event)
 
 Optional<WebViewBridge::Paintable> WebViewBridge::paintable()
 {
-    Gfx::Bitmap* bitmap = nullptr;
+    Gfx::Bitmap const* bitmap = nullptr;
     Gfx::IntSize bitmap_size;
 
     if (m_client_state.has_usable_bitmap) {

UI/AppKit/Interface/LadybirdWebViewBridge.h

@@ -42,7 +42,7 @@ public:
     void enqueue_input_event(Web::KeyEvent);
 
     struct Paintable {
-        Gfx::Bitmap& bitmap;
+        Gfx::Bitmap const& bitmap;
         Gfx::IntSize bitmap_size;
     };
     Optional<Paintable> paintable();

UI/Headless/HeadlessWebView.cpp

@@ -164,11 +164,11 @@ void HeadlessWebView::clear_content_filters()
     client().async_set_content_filters(m_client_state.page_index, {});
 }
 
-NonnullRefPtr<Core::Promise<RefPtr<Gfx::Bitmap>>> HeadlessWebView::take_screenshot()
+NonnullRefPtr<Core::Promise<RefPtr<Gfx::Bitmap const>>> HeadlessWebView::take_screenshot()
 {
     VERIFY(!m_pending_screenshot);
 
-    m_pending_screenshot = Core::Promise<RefPtr<Gfx::Bitmap>>::construct();
+    m_pending_screenshot = Core::Promise<RefPtr<Gfx::Bitmap const>>::construct();
     client().async_take_document_screenshot(0);
 
     return *m_pending_screenshot;

UI/Headless/HeadlessWebView.h

@@ -25,7 +25,7 @@ public:
 
     void clear_content_filters();
 
-    NonnullRefPtr<Core::Promise<RefPtr<Gfx::Bitmap>>> take_screenshot();
+    NonnullRefPtr<Core::Promise<RefPtr<Gfx::Bitmap const>>> take_screenshot();
 
     TestPromise& test_promise() { return *m_test_promise; }
     void on_test_complete(TestCompletion);
@@ -45,7 +45,7 @@ private:
     Core::AnonymousBuffer m_theme;
     Web::DevicePixelSize m_viewport_size;
 
-    RefPtr<Core::Promise<RefPtr<Gfx::Bitmap>>> m_pending_screenshot;
+    RefPtr<Core::Promise<RefPtr<Gfx::Bitmap const>>> m_pending_screenshot;
 
     NonnullRefPtr<TestPromise> m_test_promise;
 

UI/Headless/Test.cpp

@@ -328,7 +328,7 @@ static void run_ref_test(HeadlessWebView& view, Test& test, URL::URL const& url,
         if (Application::the().dump_failed_ref_tests) {
             warnln("\033[33;1mRef test {} failed; dumping screenshots\033[0m", test.relative_path);
 
-            auto dump_screenshot = [&](Gfx::Bitmap& bitmap, StringView path) -> ErrorOr<void> {
+            auto dump_screenshot = [&](Gfx::Bitmap const& bitmap, StringView path) -> ErrorOr<void> {
                 auto screenshot_file = TRY(Core::File::open(path, Core::File::OpenMode::Write));
                 auto encoded_data = TRY(Gfx::PNGWriter::encode(bitmap));
                 TRY(screenshot_file->write_until_depleted(encoded_data));
@@ -375,13 +375,13 @@ static void run_ref_test(HeadlessWebView& view, Test& test, URL::URL const& url,
             } else {
                 test.ref_test_expectation_type = RefTestExpectationType::Match;
             }
-            view.take_screenshot()->when_resolved([&view, &test, on_test_complete = move(on_test_complete)](RefPtr<Gfx::Bitmap> screenshot) {
+            view.take_screenshot()->when_resolved([&view, &test, on_test_complete = move(on_test_complete)](RefPtr<Gfx::Bitmap const> screenshot) {
                 test.expectation_screenshot = move(screenshot);
                 view.reset_zoom();
                 on_test_complete();
             });
         } else {
-            view.take_screenshot()->when_resolved([&view, &test](RefPtr<Gfx::Bitmap> screenshot) {
+            view.take_screenshot()->when_resolved([&view, &test](RefPtr<Gfx::Bitmap const> screenshot) {
                 test.actual_screenshot = move(screenshot);
                 view.reset_zoom();
                 view.debug_request("load-reference-page");

UI/Headless/Test.h

@@ -77,8 +77,8 @@ struct Test {
 
     Optional<RefTestExpectationType> ref_test_expectation_type {};
 
-    RefPtr<Gfx::Bitmap> actual_screenshot {};
+    RefPtr<Gfx::Bitmap const> actual_screenshot {};
-    RefPtr<Gfx::Bitmap> expectation_screenshot {};
+    RefPtr<Gfx::Bitmap const> expectation_screenshot {};
 };
 
 struct TestCompletion {