LibWebView+WebContent: Make it possible to change the painting interval

This allows us to paint at the refresh rate of the screen. The default
is 60, as before, in case it never gets set by anything.

Libraries/LibWebView/ViewImplementation.cpp

@@ -589,6 +589,7 @@ void ViewImplementation::initialize_client(CreateNewClient create_new_client)
     client().async_set_window_handle(m_client_state.page_index, m_client_state.client_handle);
 
     client().async_set_device_pixels_per_css_pixel(m_client_state.page_index, m_device_pixel_ratio);
+    client().async_set_maximum_frames_per_second(m_client_state.page_index, m_maximum_frames_per_second);
     client().async_set_system_visibility_state(m_client_state.page_index, m_system_visibility_state);
 
     if (auto webdriver_content_ipc_path = Application::browser_options().webdriver_content_ipc_path; webdriver_content_ipc_path.has_value())

Libraries/LibWebView/ViewImplementation.h

@@ -72,6 +72,7 @@ public:
     void reset_zoom();
     float zoom_level() const { return m_zoom_level; }
     float device_pixel_ratio() const { return m_device_pixel_ratio; }
+    double maximum_frames_per_second() const { return m_maximum_frames_per_second; }
 
     void enqueue_input_event(Web::InputEvent);
     void did_finish_handling_input_event(Badge<WebContentClient>, Web::EventResult event_result);
@@ -288,6 +289,7 @@ protected:
 
     float m_zoom_level { 1.0 };
     float m_device_pixel_ratio { 1.0 };
+    double m_maximum_frames_per_second { 60.0 };
 
     Queue<Web::InputEvent> m_pending_input_events;
 

Services/WebContent/ConnectionFromClient.cpp

@@ -1158,6 +1158,12 @@ void ConnectionFromClient::set_device_pixels_per_css_pixel(u64 page_id, float de
         page->set_device_pixels_per_css_pixel(device_pixels_per_css_pixel);
 }
 
+void ConnectionFromClient::set_maximum_frames_per_second(u64 page_id, double maximum_frames_per_second)
+{
+    if (auto page = this->page(page_id); page.has_value())
+        page->set_maximum_frames_per_second(maximum_frames_per_second);
+}
+
 void ConnectionFromClient::set_window_position(u64 page_id, Web::DevicePixelPoint position)
 {
     if (auto page = this->page(page_id); page.has_value())

Services/WebContent/ConnectionFromClient.h

@@ -112,6 +112,7 @@ private:
     virtual void set_has_focus(u64 page_id, bool) override;
     virtual void set_is_scripting_enabled(u64 page_id, bool) override;
     virtual void set_device_pixels_per_css_pixel(u64 page_id, float) override;
+    virtual void set_maximum_frames_per_second(u64 page_id, double) override;
     virtual void set_window_position(u64 page_id, Web::DevicePixelPoint) override;
     virtual void set_window_size(u64 page_id, Web::DevicePixelSize) override;
     virtual void did_update_window_rect(u64 page_id) override;

Services/WebContent/PageClient.cpp

@@ -68,7 +68,11 @@ PageClient::PageClient(PageHost& owner, u64 id)
 {
     setup_palette();
 
-    int refresh_interval = 1000 / 60; // FIXME: Account for the actual refresh rate of the display
+    // FIXME: This removes the decimal part, so the refresh interval will actually be higher than the maximum FPS.
+    //        For example, 60 FPS = 1000ms / 60 = 16.6666...ms, but it will become 16ms, making the interval equivalent
+    //        to 62.5 FPS.
+    int refresh_interval = static_cast<int>(1000.0 / m_maximum_frames_per_second);
+
     m_paint_refresh_timer = Core::Timer::create_repeating(refresh_interval, [] {
         Web::HTML::main_thread_event_loop().queue_task_to_update_the_rendering();
     });
@@ -202,6 +206,19 @@ void PageClient::set_viewport_size(Web::DevicePixelSize const& size)
     page().top_level_traversable()->set_viewport_size(page().device_to_css_size(size));
 }
 
+void PageClient::set_maximum_frames_per_second(u64 maximum_frames_per_second)
+{
+    m_maximum_frames_per_second = maximum_frames_per_second;
+
+    // FIXME: This removes the decimal part, so the refresh interval will actually be higher than the maximum FPS.
+    //        For example, 60 FPS = 1000ms / 60 = 16.6666...ms, but it will become 16ms, making the interval equivalent
+    //        to 62.5 FPS.
+    int refresh_interval = static_cast<int>(1000.0 / m_maximum_frames_per_second);
+
+    VERIFY(m_paint_refresh_timer);
+    m_paint_refresh_timer->set_interval(refresh_interval);
+}
+
 void PageClient::page_did_request_cursor_change(Gfx::Cursor const& cursor)
 {
     client().async_did_request_cursor_change(m_id, cursor);

Services/WebContent/PageClient.h

@@ -55,6 +55,7 @@ public:
     void set_viewport_size(Web::DevicePixelSize const&);
     void set_screen_rects(Vector<Web::DevicePixelRect, 4> const& rects, size_t main_screen_index) { m_screen_rect = rects[main_screen_index]; }
     void set_device_pixels_per_css_pixel(float device_pixels_per_css_pixel) { m_device_pixels_per_css_pixel = device_pixels_per_css_pixel; }
+    void set_maximum_frames_per_second(u64 maximum_frames_per_second);
     void set_preferred_color_scheme(Web::CSS::PreferredColorScheme);
     void set_preferred_contrast(Web::CSS::PreferredContrast);
     void set_preferred_motion(Web::CSS::PreferredMotion);
@@ -186,6 +187,7 @@ private:
     RefPtr<Gfx::PaletteImpl> m_palette_impl;
     Web::DevicePixelRect m_screen_rect;
     float m_device_pixels_per_css_pixel { 1.0f };
+    double m_maximum_frames_per_second { 60.0 };
     u64 m_id { 0 };
     bool m_has_focus { false };
 

Services/WebContent/WebContentServer.ipc

@@ -99,6 +99,7 @@ endpoint WebContentServer
     set_has_focus(u64 page_id, bool has_focus) =|
     set_is_scripting_enabled(u64 page_id, bool is_scripting_enabled) =|
     set_device_pixels_per_css_pixel(u64 page_id, float device_pixels_per_css_pixel) =|
+    set_maximum_frames_per_second(u64 page_id, double maximum_frames_per_second) =|
 
     set_window_position(u64 page_id, Web::DevicePixelPoint position) =|
     set_window_size(u64 page_id, Web::DevicePixelSize size) =|