feat: web sources frame-captured via composition (CoreWebView2CompositionController → Windows.Graphics.Capture); PNG poll + CaptureScheduler deleted

The ~30Hz CapturePreviewAsync PNG poll capped real cadence at ~20Hz
(35–165ms full-HD encode+decode), so a 60fps widget still juddered at ~1/6
speed. Replaced polling with frame-driven capture of the composition
controller's root visual — the mechanism WebView2CompositionControl and
Flutter's webview_windows use (graphics_context.cc captures the root
surface_ visual via CreateGraphicsCaptureItemFromVisual; reference:
github.com/microsoft/Windows.UI.Composition.WinUI / flutter-internal
webview_windows). Frames now arrive at the renderer's own pace; capture
memory is epoch'd ring reuse + one crop-sized shared WriteableBitmap.

New Services/WebCaptureFrameSource.cs owns GraphicsCaptureItem + free-
threaded Direct3D11CaptureFramePool + session (Straight alpha readback,
per-frame FindContentBounds → CropBounds). WebView2Manager reworked around
per-session composition controllers + one UI-thread Compositor created via
the CoreMessaging CreateDispatcherQueueController P/Invoke (the 19041
projection lacks CreateOnCurrentThread); internal seam ctor
(Dispatcher, Func<string,IScreenCaptureSource>?) for hermetic tests.
CaptureScheduler.cs deleted; the three SetCaptureInterval cadence hooks
removed; InitWebView2() moved from MainWindow ctor to Loaded (a parent
HWND must exist for the composition controller); the hidden WebViewHostPanel
overlay deleted. TransparentBackgroundScript unchanged.

Tests: WebView2ManagerTests reworked — 4 control-size + scheduler tests
dropped, FindContentBounds tests moved to WebCaptureFrameSource, ONE
integration test (Frames_PublishCroppedPreview_And_CoalesceToLatest_CarryingCropBounds)
drives the seam with a FakeWebSource + background-STA DispatcherPump.
Suite 293/293, 0 warnings.

NOTE: composition path NOT yet verified on a device — the take is the
next step. Web work committed locally only (no push per standing rule).

Docs same-commit: ai.md Slice 14 + supersede marker on Slice 11, HANDOFF,
MyMistakes (CoreMessaging DQ + namespace-landmine recipe), TASK 17,
Controls/ViewModels/Services indexes.

This commit is contained in:

Llama Chile Shop

2026-09-14 16:14:00 -07:00

parent 40c453805d

commit c01206fb8a

16 changed files with 890 additions and 581 deletions

MainWindow.xaml

-4

View File

@@ -96,10 +96,6 @@
         <!-- ═══ OVERLAY: Settings / Bug / Feature / About ═══ -->
         <controls:OverlayHost Grid.RowSpan="3"/>
         <!-- ═══ WEB SOURCE HOST: hidden panel for WebView2 controls ═══ -->
         <Canvas x:Name="WebViewHostPanel" Grid.RowSpan="4"
                 Opacity="0" IsHitTestVisible="False" Background="Transparent"/>
         <!-- ═══ TOASTS: non-blocking notifications (bottom-right, above footer) ═══ -->
         <notifications:NotificationArea x:Name="ToastArea"
                                         Grid.RowSpan="4"