Also switched the D3D11 and D3D12 renderers to use real NV12 textures for NV12 data.
The combination of these two changes allows us to implement 0-copy video decode and playback for D3D11 in testffmpeg without any access to the renderer internals.
This avoids assuming that the pixels are suitably aligned for direct
access, which there's no guarantee that they are; in particular,
3-bytes-per-pixel RGB images are likely to have 3 out of 4 pixels
misaligned. On x86, dereferencing a misaligned pointer does what you
would expect, but on other architectures it's undefined whether it will
work, crash with SIGBUS, or silently give a wrong answer.
Signed-off-by: Simon McVittie <smcv@collabora.com>
We can't rely on irrational numbers like pi being represented exactly,
particularly when compiling for i386, where the i387 floating-point
interface carries out calculations in registers that have higher
precision than the actual double-precision variable. The 1980s were a
strange time.
Resolves: https://github.com/libsdl-org/SDL/issues/8311
Signed-off-by: Simon McVittie <smcv@collabora.com>
Now it offers the total requested bytes in addition to the amount
immediately needed (and immediately needed might be zero if the stream
already has enough queued to satisfy the request.
You can see it in action in testaudio by mousing over a logical device; it
will show a visualizer for the current PCM (whatever is currently being
recorded on a capture device, or whatever is being mixed for output on
playback devices).
Fixes#8122.
This is meant to offer a simplified API for people that are either migrating
directly from SDL2 with minimal effort or just want to make noise without
any of the fancy new API features.
Users of this API can just deal with a single SDL_AudioStream as their only
object/handle into the audio subsystem.
They are still allowed to open multiple devices (or open the same device
multiple times), but cannot change stream bindings on logical devices opened
through this function.
Destroying the single audio stream will also close the logical device behind
the scenes.
Sam Lantinga
Ryan C. Gordon
Anonymous Maarten
Ozkan Sezer
Simon McVittie
Frank Praznik
Brick