If users update geometry related properties very frequently
for a stream to be animated, redrawing on every update
can make rendering choppy or can be a performance bottleneck.
To address the issue, adding a property to control the behavior
of redrawing scene when geometry related properties are updated.
Also, do not resize swapchain on such property update, since
re-allocating backbuffer and multi-sampled render target is
unnecessary in that case.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5575>
Deadlock sequence:
* From a streaming thread, d3d11videosink sends synchronous message
to the parent window, so that internal (child) window can be
constructed on the parent window's thread
* App thread (parent window thread) is waiting for pipeline's
state change (to GST_STATE_NULL) but streaming thread is
blocked and waiting for app thread
To avoid the deadlock, GstD3D11WindowWin32 should send message
to the parent window asynchronously.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3570>
The "present" signal will be emitted just before the
IDXGISwapChain::Present() call. The client can perform additional
GPU operation with given GstD3D11Device object and
ID3D11RenderTargetView handle. Or, the client can read back
the scene to be displayed on window using the signal.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2923>