winrt: Introduce DirectX pipeline bypass.

Qt Windows Runtime camera uses DirectVideo to convert NV12 format
texture to BGRA format texture. As the EGL Node can draw using NV12
already, allow video render control to choose which path to take. By
default use DirectVideo. Bypass can be used as fallback when
DirectVideo cannot be used or is not working.

Task-Id: QTBUG-48331
Change-Id: I0cb87a7c4523bfb60610e6b41ab3fb05aff092a1
Reviewed-by: Andrew Knight <andrew.knight@intopalo.com>

1 files changed, 89 insertions, 23 deletions

diff --git a/src/plugins/winrt/qwinrtabstractvideorenderercontrol.cpp b/src/plugins/winrt/qwinrtabstractvideorenderercontrol.cpp
index 4a225e9ce..cf62843f7 100644
--- a/src/plugins/winrt/qwinrtabstractvideorenderercontrol.cpp
+++ b/src/plugins/winrt/qwinrtabstractvideorenderercontrol.cpp
@@ -182,6 +182,8 @@ public:
 
     QThread renderThread;
     bool active;
+    QWinRTAbstractVideoRendererControl::BlitMode blitMode;
+    CRITICAL_SECTION mutex;
 };
 
 ID3D11Device *QWinRTAbstractVideoRendererControl::d3dDevice()
@@ -212,6 +214,8 @@ QWinRTAbstractVideoRendererControl::QWinRTAbstractVideoRendererControl(const QSi
     d->eglConfig = 0;
     d->eglSurface = EGL_NO_SURFACE;
     d->active = false;
+    d->blitMode = DirectVideo;
+    InitializeCriticalSectionEx(&d->mutex, 0, 0);
 
     connect(&d->renderThread, &QThread::started,
             this, &QWinRTAbstractVideoRendererControl::syncAndRender,
@@ -220,7 +224,11 @@ QWinRTAbstractVideoRendererControl::QWinRTAbstractVideoRendererControl(const QSi
 
 QWinRTAbstractVideoRendererControl::~QWinRTAbstractVideoRendererControl()
 {
+    Q_D(QWinRTAbstractVideoRendererControl);
+    CriticalSectionLocker locker(&d->mutex);
     shutdown();
+    DeleteCriticalSection(&d->mutex);
+    eglDestroySurface(d->eglDisplay, d->eglSurface);
 }
 
 QAbstractVideoSurface *QWinRTAbstractVideoRendererControl::surface() const
@@ -244,31 +252,45 @@ void QWinRTAbstractVideoRendererControl::syncAndRender()
     forever {
         if (currentThread->isInterruptionRequested())
             break;
+        {
+            CriticalSectionLocker lock(&d->mutex);
+            HRESULT hr;
+            if (d->dirtyState == TextureDirty) {
+                CD3D11_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM, d->format.frameWidth(), d->format.frameHeight(), 1, 1);
+                desc.BindFlags |= D3D11_BIND_RENDER_TARGET;
+                desc.MiscFlags = D3D11_RESOURCE_MISC_SHARED;
+                hr = g->device->CreateTexture2D(&desc, NULL, d->texture.ReleaseAndGetAddressOf());
+                BREAK_IF_FAILED("Failed to get create video texture");
+                ComPtr<IDXGIResource> resource;
+                hr = d->texture.As(&resource);
+                BREAK_IF_FAILED("Failed to cast texture to resource");
+                hr = resource->GetSharedHandle(&d->shareHandle);
+                BREAK_IF_FAILED("Failed to get texture share handle");
+                d->dirtyState = SurfaceDirty;
+            }
 
-        HRESULT hr;
-        if (d->dirtyState == TextureDirty) {
-            CD3D11_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM, d->format.frameWidth(), d->format.frameHeight(), 1, 1);
-            desc.BindFlags |= D3D11_BIND_RENDER_TARGET;
-            desc.MiscFlags = D3D11_RESOURCE_MISC_SHARED;
-            hr = g->device->CreateTexture2D(&desc, NULL, d->texture.ReleaseAndGetAddressOf());
-            BREAK_IF_FAILED("Failed to get create video texture");
-            ComPtr<IDXGIResource> resource;
-            hr = d->texture.As(&resource);
-            BREAK_IF_FAILED("Failed to cast texture to resource");
-            hr = resource->GetSharedHandle(&d->shareHandle);
-            BREAK_IF_FAILED("Failed to get texture share handle");
-            d->dirtyState = SurfaceDirty;
-        }
-
-        hr = g->output->WaitForVBlank();
-        CONTINUE_IF_FAILED("Failed to wait for vertical blank");
+            hr = g->output->WaitForVBlank();
+            CONTINUE_IF_FAILED("Failed to wait for vertical blank");
+
+            bool success = false;
+            switch (d->blitMode) {
+            case DirectVideo:
+                success = render(d->texture.Get());
+                break;
+            case MediaFoundation:
+                success = dequeueFrame(&d->presentFrame);
+                break;
+            default:
+                success = false;
+            }
 
-        if (!render(d->texture.Get()))
-            continue;
+            if (!success)
+                continue;
 
-        // Queue to the control's thread for presentation
-        present.invoke(this, Qt::QueuedConnection);
-        currentThread->eventDispatcher()->processEvents(QEventLoop::AllEvents);
+            // Queue to the control's thread for presentation
+            present.invoke(this, Qt::QueuedConnection);
+            currentThread->eventDispatcher()->processEvents(QEventLoop::AllEvents);
+        }
     }
 
     // All done, exit render loop
@@ -326,7 +348,44 @@ void QWinRTAbstractVideoRendererControl::setActive(bool active)
         d->surface->stop();
 }
 
-void QWinRTAbstractVideoRendererControl::present()
+QWinRTAbstractVideoRendererControl::BlitMode QWinRTAbstractVideoRendererControl::blitMode() const
+{
+    Q_D(const QWinRTAbstractVideoRendererControl);
+    return d->blitMode;
+}
+
+void QWinRTAbstractVideoRendererControl::setBlitMode(QWinRTAbstractVideoRendererControl::BlitMode mode)
+{
+    Q_D(QWinRTAbstractVideoRendererControl);
+    CriticalSectionLocker lock(&d->mutex);
+
+    if (d->blitMode == mode)
+        return;
+
+    d->blitMode = mode;
+    d->dirtyState = d->blitMode == MediaFoundation ? NotDirty : TextureDirty;
+
+    if (d->blitMode == DirectVideo)
+        return;
+
+    if (d->texture) {
+        d->texture.Reset();
+        d->shareHandle = 0;
+    }
+
+    if (d->eglSurface) {
+        eglDestroySurface(d->eglDisplay, d->eglSurface);
+        d->eglSurface = EGL_NO_SURFACE;
+    }
+}
+
+bool QWinRTAbstractVideoRendererControl::dequeueFrame(QVideoFrame *frame)
+{
+    Q_UNUSED(frame)
+    return false;
+}
+
+void QWinRTAbstractVideoRendererControl::textureToFrame()
 {
     Q_D(QWinRTAbstractVideoRendererControl);
 
@@ -387,6 +446,13 @@ void QWinRTAbstractVideoRendererControl::present()
 
         d->dirtyState = NotDirty;
     }
+}
+
+void QWinRTAbstractVideoRendererControl::present()
+{
+    Q_D(QWinRTAbstractVideoRendererControl);
+    if (d->blitMode == DirectVideo)
+        textureToFrame();
 
     // Present the frame
     d->surface->present(d->presentFrame);