This improves the documentation by exposing a C++-idiomatic way to
handle the resources without leaking for most users copying this part of
the code to their application.
QOpenGLFramebufferObject::takeTexture is detaching the current texture
and transfering ownership to the caller, and the texture was never
destroyed afterwards. It was leading to a huge memory consumption and
leak when using the sample app.
From the documentation[^1] in Qt5:
Returns the texture id for the texture attached to this framebuffer
object. The ownership of the texture is transferred to the caller.
If the framebuffer object is currently bound, an implicit release()
will be done. During the next call to bind() a new texture will be
created.
[1]: https://doc.qt.io/qt-5/qopenglframebufferobject.html#takeTexture
Co-authored-by: Alexandre Janniaux <ajanni@videolabs.io>
For the commit message and cleaning the fix mostly.
Fixes#25867
Precision is available but no-op on GLSL 130 (see [3], section 4.5.2)
and mandatory for OpenGL ES. It was first reserved on GLSL 120 and
didn't exist in GLSL <= 110 (= OpenGL 2.0). Since it's a no-op, the
easiest solution is to never use it for OpenGL code.
This description is also copied into the sample to explain to the users
that they might have difference in behaviour depending on whether they
are using OpenGL or OpenGL ES2, and depending on the version of OpenGL
used.
The precision qualifier was added because Qt was linked from the
contribs, which was linked with -opengl angle and thus was actually
using OpenGL ES2, which needs the precision qualifier.
Resources used:
[1]: https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.1.10.pdf
[2]: https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.1.20.pdf
[3]: https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.1.30.pdf
On Windows if I don't set this I get the following error:
QOpenGLShader::compile(Fragment): ERROR: 0:3: '' : No precision specified for (float)
ERROR: 0:8: ';' : syntax error
VLCVideo was not released, probably because it was considered like a
QObject (new VLCVideo(this)) and thus expected to be destroyed
automatically like a QObject.
Use a std::unique_ptr<> to destroy it when the parent widget is
destroyed.
We don't need to display avcodec logs typically, and we mostly want to
give feedback to the user about what is loaded and what is happening,
meaning info, error, warn, dbg.
We're waiting for the surface to be available and protecting the surface
from having multiple clients at the same time, but it typically didn't
return the token when cleanup(), meaning that any second open was
actually a deadlock in the waiting.
cfg, out, width and height are needed when the user want to adapt the
aspect ratio of the video on the rendering surface, but the sample
doesn't show this, so silence the warnings anyway.
Since there were two threads running concurrently for the same context,
eglMakeCurrent could fail almost everytime.
When two such threads exist, different OpenGL context must be assigned
to each of them and the correct resource sharing mechanism must be
enabled so that the rendering thread can use the resources generated by
the producing (VLC) thread.
In addition, we need the OpenGL context from the actual window for the
rendering, which will not be available right in the constructor, so
synchronize its creation through a semaphore, delaying the opening of
the vglmem module on the VLC side until the video is ready to be
rendered on the Qt side too.
Now that we use a union we can differentiate each properly.
In particular the D3D9 is an unsigned FourCC.
It's still not as strongly typed as it could be (no DXGI_FORMAT for example).
VLC adjusts the text rendering based on the rendering area size, so we should
be able to adapt to changes in the host app.
This is using the wextern dummy window, like it's done with D3D callbacks. The
callback is given to the host app when the window is enabled and reset when the
window is disabled.
Not sure how it's supposed to be done with Android but given it uses a
regular window, it probably reports size changes already.
Rémi Denis-Courmont
Steve Lhomme
Alexandre Janniaux
Craig Turner