Table of Contents

Interface IVideoSurfaceProvider

Namespace
VisioForge.Core.UI.WPF
Assembly
VisioForge.Core.dll

Exposed by WPF VideoView when it runs in the VisioForge.Core.Types.VideoRendererMode.D3D11Composable mode. The provider owns a single BGRA8 D3D11 shared texture; its handle (VisioForge.Core.UI.WPF.IVideoSurfaceProvider.SharedTextureHandle) is stable for the lifetime of the current internal texture and may be reset to Zero on resize, device-removed / TDR, unsupported pixel format upstream, or disposal. See VisioForge.Core.UI.WPF.IVideoSurfaceProvider.SharedTextureHandle for the full list.

public interface IVideoSurfaceProvider

Remarks

Typical use: subscribe to VisioForge.Core.UI.WPF.IVideoSurfaceProvider.FrameReady, open the shared handle on your own ID3D11Device, run a compute or pixel shader that reads from and writes to the texture, then return. The mutated frame is what WPF presents this compose cycle.

Properties

SharedTextureHandle

DXGI shared handle of the current frame's GPU texture, BGRA8. Stable for the lifetime of the current internal texture and reset to Zero when:

  • no frame has been pushed yet,
  • the source resolution changed (a new texture is allocated and the published handle is replaced),
  • frame upload failed (e.g. device removed / TDR, driver crash, unsupported pixel format) — the pipeline tears down the texture and the next successful upload publishes a new handle,
  • the view was disposed.
Consumers must re-read this property per frame; do not cache. 
nint SharedTextureHandle { get; }

Property Value

nint

SurfaceHeight

Height of the current shared texture, in pixels.

int SurfaceHeight { get; }

Property Value

int

SurfaceWidth

Width of the current shared texture, in pixels.

int SurfaceWidth { get; }

Property Value

int

FrameReady

Raised after each frame has been uploaded to the shared texture and before WPF presents it. Subscribers may mutate the texture in place (within an Acquire/Release pair on their own ID3D11Device); the modified pixels are what the user will see this compose cycle.

event EventHandler<VideoSurfaceFrameEventArgs> FrameReady

Event Type

EventHandler<VideoSurfaceFrameEventArgs>

Remarks

Thread affinity: the event is invoked synchronously on the same thread that called the underlying PushFrame — typically a DirectShow callback thread, a GStreamer streaming thread, or any thread the consumer chooses when driving the VisioForge.Core.UI.WPF.VideoView manually. Subscribers must NOT assume the WPF dispatcher thread and must NOT assume the same thread across frames; do not capture SynchronizationContext.Current or thread-affine D3D resources inside the handler.

RenderError

Raised when the underlying D3D11 render pipeline encounters a non-fatal error: shared-texture upload failure, device-removed / TDR, D3DImage bridge construction failure, dispatcher rejection during teardown, or a consumer-supplied VisioForge.Core.UI.WPF.IVideoSurfaceProvider.FrameReady handler throwing. Subscribers can log, surface a UI banner, or reset their own state without attaching a debugger. Consumer exceptions thrown from this handler are swallowed so a misbehaving subscriber cannot break the pipeline.

event EventHandler<Exception> RenderError

Event Type

EventHandler<Exception>

Remarks

Thread affinity: the event is invoked synchronously on the thread where the error was raised — typically a streaming thread, the WPF dispatcher, or a finalizer/teardown thread. Subscribers must NOT assume any particular thread, must NOT block, and must NOT re-enter VisioForge.Core.UI.WPF.IVideoSurfaceProvider members synchronously (handlers that read VisioForge.Core.UI.WPF.IVideoSurfaceProvider.SharedTextureHandle / VisioForge.Core.UI.WPF.IVideoSurfaceProvider.SurfaceWidth / VisioForge.Core.UI.WPF.IVideoSurfaceProvider.SurfaceHeight from a foreign thread can race with the disposing render path).