Direct3D11 objects are COM, and most COM C APIs are verbose
(C++ is a little better). So, by using C++ APIs, we can make code
shorter and more readable.
Moreover, "ComPtr" helper class (which is C++ only) can be
utilized, that is very helpful for avoiding error-prone COM refcounting
issue/leak.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2077>
Since our decoder DPB texture pool cannot be grown once it's
configured, we should pre-allocate sufficient number of textures
for zero-copy playback (but not too many).
The "min buffers" allocation query parameter can be a hint for
the number of required textures in addition to DPB size.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2017>
Unlike other stateless decoder implementations (e.g., VA),
our DPB pool cannot be grown since we are using
texture array (pre-allocated, fixed-size d3d11 texture pool).
So, if there's no more available texture to use,
there's no way other than copying it to downstream's
d3d11 buffer pool. Otherwise deadlock will happen.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2003>
Move d3d11 device, memory, buffer pool and minimal method
to gst-libs so that other plugins can access d3d11 resource.
Since Direct3D is primary graphics API on Windows, we need
this infrastructure for various plugins can share GPU resource
without downloading GPU memory.
Note that this implementation is public only for -bad scope
for now.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/464>
Hide most of symbols of GstD3D11Memory object.
GstD3D11Memory is one of primary resource for imcoming d3d11 library
and it's expected to be a extensible feature.
Hiding implementation detail would be helpful for later use case.
Summary of this commit:
* Now all native Direct3D11 resources are private of GstD3D11Memory.
To access native resources, getter methods need to be used
or generic map (e.g., gst_memory_map) API should be called
apart from some exceptional case such as d3d11decoder case.
* Various helper methods are added for GstBuffer related operations
and in order to remove duplicated code.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1892>
