Using g_thread_join() in _finalize() handlers may result in a deadlock
joining the current thread when the last reference is held by a signal
handler.
e.g.:
error 'Resource deadlock avoided' during 'pthread_join (pt->system_thread, NULL)'
The backtrace looks like this:
[...]
g_thread_join ()
gst_gl_window_finalize ()
gst_gl_window_x11_finalize ()
g_object_unref ()
g_value_unset ()
g_signal_emit_valist ()
g_signal_emit ()
gst_gl_window_send_mouse_event ()
gst_gl_window_mouse_event_cb ()
g_main_dispatch ()
[..]
g_main_loop_run ()
gst_gl_window_navigation_thread ()
g_thread_proxy ()
start_thread ()
clone ()
We cannot set the x, y coordinate of the video frame at the dispmanx at
this point. We need to teach dispmanx backend to understand about
set_render_rectangle API to draw a video with other UI.
This patch keeps the current behavior which places video frame at the
center of the display if there is no set_render_rectangle call to the
dispmanx window.
https://bugzilla.gnome.org/show_bug.cgi?id=766018
e.g. passing with_gl_api=gles2 would still build the glx code but not be
linking against the libGL library which is where the glX* functions are
located and would result in a linker error.
Solved by checking for the libGL library if either opengl or glx may be
needed and then disabling the corresponding deps as requested.
The tests were broken since 91fea30, which changed glupload to return
GST_GL_UPLOAD_RECONFIGURE if the texture target in the input buffers doesn't
match the texture-target configured in the output caps.
This commit fixes that and adds more checks for the new behaviour.
Now when used with video/x-raw as input, the GLMemoryUpload method checks for
->tex_target in input GLMemory(es) and sets the output texture-target
accordingly.
Fixes video corruption with a pipeline like avfvideosrc ! video/x-raw !
glimagesink where on macos avfvideosrc pushes RECTANGLE textures but glupload
was configuring texture-target=2D as output.
Don't set the chosen texture-target into the wrong structure.
The input caps may not be writable, and in any case - the
intention was to configure the othercaps. Also, remove an
extra unref - the othercaps ref is consumed by
gst_caps_make_writable already.
https://github.com/mesonbuild/meson
With contributions from:
Tim-Philipp Müller <tim@centricular.com>
Matej Knopp <matej.knopp@gmail.com>
Jussi Pakkanen <jpakkane@gmail.com> (original port)
Highlights of the features provided are:
* Faster builds on Linux (~40-50% faster)
* The ability to build with MSVC on Windows
* Generate Visual Studio project files
* Generate XCode project files
* Much faster builds on Windows (on-par with Linux)
* Seriously fast configure and building on embedded
... and many more. For more details see:
http://blog.nirbheek.in/2016/05/gstreamer-and-meson-new-hope.htmlhttp://blog.nirbheek.in/2016/07/building-and-developing-gstreamer-using.html
Building with Meson should work on both Linux and Windows, but may
need a few more tweaks on other operating systems.
Multiple threads may be accessing the wayland fd at the same time which
requires the use of special wayland API to deal with to ensure nobody
will steal reads and cause a stall for anyone else.
When connect to qmlglsrc, x11 event loop will be replace by qt event loop
which will cause the window cannot receive event from xserver, such as resize
https://bugzilla.gnome.org/show_bug.cgi?id=768160
Makes infinitely more sense and implementation were expecting that behaviour
anyway and would enter a resize, draw, resize, draw, ... cycle instead of only
resizing once.
There's no need for the jump to an extra thread in most cases, especially
when relying solely on a shader to render. We can use the provided
render_to_target() functions to simplify filter writing.
Facilities are given to create fbo's and attach GL memory (renderbuffers
or textures). It also keeps track of the renderable size for use with
effective use with glViewport().
Calling glUniformMatrix before the shader is bound is invalid and
would result in errors like:
GL_INVALID_OPERATION in glUniformMatrix(program not linked)
Move glUniformMatrix() to after the gst_gl_shader_use() call.
Rather than assuming something. e.g. zerocopy on iOS with GLES3 requires
the use of Luminance/Luminance Alpha formats and does not work with
Red/RG textures.
Take the used texture type from the memory instead.
Fixes conversion from multi-planar YUV formats with two components per plane
(NV12, NV21, YUY2, UYVY, GRAY16_*, etc) with Luminance Alpha input textures.
This is also needed for zerocopy decoding on iOS with GLES 3.x.
The intention was to assert if both maj and min were NULL (as there would be no
point calling the function). Instead if either maj or min were NULL, the assert
would occur.
Fix that.
Newer devices require using a different GLSL extension for accessing
external-oes textures in a shader using the texture() functions.
While the GL_OES_EGL_image_external_essl3 should supposedly be supported
on a any GLES3 android device, the extension was defined after a lot of the
older drivers were built so they will not know about it. Thus there are two
possible interpretations of which of texture[2D]() should be supported for
external-oes textures. Strict adherence to the GL_OES_EGL_image_external
extension spec which uses texture2D() or following GLES3's pattern, also
allowing texture() as a function for accessing external-oes textures
This adds another mangling pass to convert
#extension GL_OES_EGL_image_external : ...
into
#extension GL_OES_EGL_image_external_essl3 : ...
on GLES3 and when the GL_OES_EGL_image_external_essl3 extension is supported.
Only uses texture() when the GLES3 and the GL_OES_EGL_image_external_essl3
extension is supported for external-oes textures.
Uses GLES2 + texture2D() + GL_OES_EGL_image_external in all other external-oes
cases.
https://bugzilla.gnome.org/show_bug.cgi?id=766993
Otherwise we will leak GstGLContext's when adding the same context more than
once.
Fixes a regression caused by 5f9d10f603 in the
gstglcontext unit test that failed with:
Assertion 'tmp == NULL' failed
Provide a function to get the affine matrix in the meta in terms of NDC
coordinates and use as a standard opengl matrix.
Also advertise support for the affine transformation meta in the allocation
query.
Because current GstEGLImageMemory does not inherit GstGLMemory, GLUpload
allocates additional GLMemory and upload the decoded contents from the decoder
which uses EGLImage (e.g. gst-omx in RPi).
This work adds GstGLMemoryEGL to avoid this overhead. Decoders allocate
GstGLMemoryEGL and decode its contents to the EGLImage of GstGLMemoryEGL. And
GLUpload uses this memory without allocation of additional textures and blit
operations.
[Matthew Waters]: gst-indent the sources and fix a critical retreiving the egl
display from the memory.
https://bugzilla.gnome.org/show_bug.cgi?id=760916
Allows creating wrapped memories with GstGLAllocationParams.
The wrapped pointers will be set in the parameters before being passed
to the memory allocation function.
Some platforms provide an old version of GLES2/gl2.h and GLES2/gl2ext.h that
will fail when including GLES3/gl3.h due to missing typedef's.
Seen on the RPi.
Don't create many short lived locks/conds in gst_gl_window_send_message. This is
a micro optimization to save a bunch of pthread_* calls which are expensive on
OSX/iOS and possibly other platforms.
while calling eglCreateImage without a GL context current in the executing
thread works on the RPi, some other implementations will return errors.
Marshall the eglCreateImage to the GL thread to appease these implementations.
There are numerous slight differences required between Desktop GL and GLES3 for
multiple render targets.
1. gl_FragData doesn't exist at all and one is required to use
'layout (location = ?) out ...' instead.
2. gl_FragColor doesn't exist, same as 1
3. texture2D() has been deprecated
Fortunately most of these have been taken care of with GL3 and the shader
mangling already exists so just expand the conditions they are used in. The
gl_FragData issue requires a new mangle pass though. We also use this new
pass on desktop GL for consistency.
By default, reading GL_RED or GL_RG us unsupported by glReadPixels unless
exposed through GL_COLOR_READ_IMPLEMENTATION_FORMAT/TYPE. This allows
downloading multiple-planar video frames where possible.
There are some cases where it's needed for binding in/out variables in shaders.
e.g. glsl 150 (gl 3.2) doesn't support the 'layout (location = ?)' specifiers in
the shader source so we have to bind them ourselves.
Without the GST_GL_API_GLES2 bit set, we will not even attempt to look
for the function pointers in the core library and will fallback to
glFlush/glFinish.
If the user uploads their own texture without setting the unpack length, then
then the result will have the appearance of stride mismanagement due to
an incorrect row length.
If we are given caps with extra features (like the overlay composition
features), we can only deal with that when we are in passthrough mode.
Previously we were bailing entirely and not allowing passthrough filter elements
with things like textoverlay.
Fixes the following pipeline (assuming glfilter supports passthrough):
gl ! textoverlay ! glfilter ! ... ! glimagesinkelement
https://bugzilla.gnome.org/show_bug.cgi?id=763756
When transforming, xplode it out into the necessary caps features both
with and without the passthough features.
Fixes negotiation in the following class of pipelines:
gl ! textoverlay ! glupload ! glimagesinkelement
https://bugzilla.gnome.org/show_bug.cgi?id=763756
GL 1.4 (with GL_ARB_shader_objects) doesn't have glIsProgram or glIsShader
equivalents. As they are simply assertions, skip them when there isn't a
valid function pointer.
With e38af23044 returning the correct contexts,
gst_gl_display_add_context() was susceptible to causing infinte loops when
adding the same GstGLContext more than once. Fix and add a test for
gst_gl_display_add_context().
Fixes glvideomixer gst-validate tests.
Execute GL calls without marshalling them to the context thread. In the cocoa
and eagl backends calling gst_gl_context_activate is cheap and therefore calling
it on the current thread and serializing GL calls with a per-context lock is
more efficient (faster and has less overhead) than marshalling everything to the
context thread.
This optimization cuts a large overhead in g_poll (continuously waking up the
context thread) and in g_mutex_*/g_cond_* (waiting for results from the context
thread).
When requesting a glcontext (regardless of thread), the result was correct.
However, when requesting current glcontext on a specific thread, it could
come up with a glcontext active on another thread.
https://bugzilla.gnome.org/show_bug.cgi?id=763168
Maxsize is initialized once and should never change. Allocating data
should have no impact on the selected max size for this memory. This
causing memory map failure as the maxsize would become smaller then
size. This happened when using direct rendering in avviddec on GL that
does not support PBO transfer.
https://bugzilla.gnome.org/show_bug.cgi?id=763045
Intended for use with wrapped contexts that are created shared with gst's
gl contexts in order to manage the internal sharegroup state correctly.
e.g. with caopengllayer (which is used in glimagesink and caopengllayersink
on OS X), we create a CGL context from the gst context and the sharing state
was not being correctly set on either GL context and gst_gl_context_is_shared()
was always returning FALSE.
With 11fb4fff80 only flushing with multiple
shared contexts, the required flush was not occuring causing screen
corruption or stuttering.
Note: this didn't affect GST_GL_API=opengl pipelines
https://bugzilla.gnome.org/show_bug.cgi?id=762620
Usually gl debug is initialized in gst_gl_context_create_thread.
But this function is not used when using the GstGLContextGPUProcess
from ChromiumGStreamerBackend.
Received signal 11 SEGV_MAPERR 000000000000
gst_debug_category_get_threshold
gst_gl_insert_debug_marker
gst_gl_base_filter_gl_start
CC libgstgl_x11_la-gstglcontext_glx.lo
In file included from gstglcontext_glx.c:39:0:
../utils/opengl_versions.h:52:43: error: ‘gles2_versions’ defined but not used [-Werror=unused-const-variable]
static const struct { int major, minor; } gles2_versions[] = {
^~~~~~~~~~~~~~
Invoke the callback right away when called on the context thread. Removes
overhead when nesting libgstgl calls (for example when working with the sync
meta).
CPU waits are more expensive and are only required if the CPU is ever going to
access the data. GPU waits perform inter-context synchronisation and are cheaper
as they don't require CPU intervention.
All uses of query->context in gstglquery.c assume it exists. We can assume
this as well before unrefing it. Furthermore, gst_object_unref() will just
silently return if it ever were to not exist.
Improves the responsiveness of the pipeline when resources are close/above the
limitations of the hardware.
Any subclass that wishes not to enable qos can do so themselves.
https://bugzilla.gnome.org/show_bug.cgi?id=761519
This reverts commit 96b9666d59.
This reverts commit d11385d167.
This breaks the texture sharing with the applemedia elements as
CVOpenGLESTextureCache seems to have an arbitrary restriction on GLES2 only.
We may need them to transform into a different set of formats.
Fixes YUV->YUV with two glcolorconverts, e.g:
format=I420 ! glcolorconvert ! glcolorconvert ! format=NV12
1.0 / width does not offset by one pixel in rectangular textures (which use
unnormalized coordinates).
Provide the actual pixel offset as a uniform to the shader.
1. Correctly describe what we can caps we can transform to/from.
i.e. no YUV->YUV or GRAY->YUV or YUV->GRAY (except for passthrough).
2. Prefer similar formats and ignore incompatible formats on fixation.
Useful when gst_gl_window.c::gst_gl_window_new is not used.
This is the case when using a custom GstGLWindow.
(ex: GstGLWindowGPUProcess from Chromium)
The messages are stored by gst_gl_async_debug_store_log_msg() and output later
by a corresponding store(), output() or an unset()/free().
Some wrapper macros are provided to avoid callers explicitly using __FILE__,
GST_FUNCTION and __LINE__
This makes a pipeline like:
... ! video/x-raw(memory:GLMemory),format=UYVY ! glcolorconvert !
video/x-raw(memory:GLMemory),format={UYVY, NV12} ! ...
passthrough instead of converting UYVY => NV12. The conversion would happen
before this change since the element (and basetransform) transform the src caps
to format={NV12, UYVY} (since NV12 comes first in the glcolorconvert:src
template) and then the default caps fixate func would fixate to NV12. Blah.
Also there's no need to intersect against the template caps in ::transform_caps
since basetransform does that right after calling the vfunc.
The optimistic download_transfer was not setting the required flag to not
perform glReadPixels on subsequent map (READ). resulting in glReadPixels
happening twice.
Some operations are unnecessary when running with only a single GL
context.
e.g. glFlush when setting a fence object as the flush happens on wait.
API: gst_gl_context_is_shared
1. Various elements/base classes only perform a subset check on accept-caps
2. Some GL elements have texture-target in their pad template
3. When checking subsets, only the caps to check are allowed to contain extra
fields. If the 'template' caps have extra fields, the subset fails.
Thus without texture-target on the caps, various accept-caps implementations
were failing.
Also, add some convenience functions for setting and retrieving
texture targets to/from GValue.
https://bugzilla.gnome.org/show_bug.cgi?id=759860
GL 2.1 only supports pbo upload.
The wrapped data pointer was only being set on the pbo memory and on the
glmemory so when a download was requested (in GL 2.1), glmemory was
allocating a new data pointer and thus not returning the wrapped data.
Exposing the navigation thread's main context, GSourceFuncs and structs called
key_event and mouse_event is exposing a bit too much of the internals. Let's
just go with two functions to asynchronously send navigation events on the
window with the same API as the synchronous ones.
This upload method detect and optimize uploads of DMABuf memory. This is
done by creating and caching EGLImages wrapper around DMABuf. The
EGLImages are then binded to a texture which get converter using
standard shader.
Example pipeline:
GST_GL_PLATFORM=egl \
gst-launch-1.0 v4l2src device=/dev/video1 io-mode=4 ! \
video/x-raw,format=NV12 ! glimagesink
https://bugzilla.gnome.org/show_bug.cgi?id=743345
Maps GstVideoFormats to suitable DRM fourccs which work with
glcolorconvert, using gst_gl_memory_alloc(). We require mostly
only 4 formats to be supported by the driver. We require DRM
equivalent to RGB16, RGBA, R8 and RG88. This way it's compatible with
DesktopGL, since GL_TEXTURE_2D is used and limit driver requirements.
With this we can virtually support all formats the glcolorconvert
supports.
https://bugzilla.gnome.org/show_bug.cgi?id=743345
Add gst_gl_memory_allocator_get_default to get the default allocator based on
the opengl version. Allows us to stop hardcoding the PBO allocator which isn't
supported on gles2.
Fixes GL upload on iOS9 among other things.
e.g when wrapping a data pointer we don't want to map/unmap off the end of
pointer with the alignment bytes.
Instead track that information separately as maxsize is used for mapping by
GstMemory and thus represents a size without any alignment padding bytes.
Requires the usage of GstGLVideoAllocationParams however any user can set their
own parameters along with an allocator which will be used to allocate the
correct memory type.
- Create GstGLVideoAllocationParams which is a GstGLAllocationParams subclass.
- Make it possible to allocate glmemory objects directly if no frills are
needed.
This is made possible by a subclassable GstGLAllocationParams that holds
the allocation parameters
Every allocation would now go through gst_gl_base_memory_alloc with the
allocation parameters now being specified in a single struct to allow
extension by different allocators.
The imported memory has already been allocated, passing allocation
parameters with alignment confuses the memory which endup with a
size different from maxsize and lead to overrun when the memory
is being copied.
GCC automatically disable redundance warnings for system headers. As
soon as we start using a non-system installed mesa, we would start
having issues. The test for both wasn't setting any flags, so it would
work but then fail at runtime.
This is being fixed by disabling in the code (where needed only) that
GCC warning. The test is also fixed to avoid the false positive we had.
The base class is useful for having multiple backing memory types other
than the default. e.g. IOSurface, EGLImage, dmabuf?
The PBO transfer logic is now inside GstGLMemoryPBO which uses GstGLBuffer
to manage the PBO memory.
This also moves the format utility functions into their own file.
Heavily based on GstGLBaseBuffer that is a subclass of GstGLBaseMemory.
Provides GPU and CPU accessible GL buffer objects by GL handle or by
sysmem data pointer.
It handles the following
- GstAllocationParams -> gst_memory_init transformation
- Makes sure that map/unmap/create/destroy happen on the GL thread with
a GL context current.
- Holds a possible sysmem accessible data pointer with alignment.
- Holds the need upload/download transfer state
Rectangle textures don't use normalized coordinates so subsampling needs to be
factored in explicitly.
Fixes YUV => RGB conversion for rectangle textures.
To use GLMemory and EGLImage allocators, one need to know the
libgstgl API. This is only expected if the associated caps features
have been negotiated. Generic element that otherwise receive those
allocators may fail, resulting in broken pieline. We don't want to
force all generic element to check if the allocator is a custom
allocator or a normal allocator (which implement the _alloc method).
https://bugzilla.gnome.org/show_bug.cgi?id=758877
gstglsyncmeta.c -fPIC -DPIC -o .libs/libgstgl_1.0_la-gstglsyncmeta.o
gstglsyncmeta.c: In function 'gst_buffer_add_gl_sync_meta':
gstglsyncmeta.c:131:1: error: control reaches end of non-void function [-Werror=return-type]
}
^
there could be other ways/requirements for synchronising two GPU command
streams (whether GL or platform specific).
e.g. glfencesync/eglwaitnative/cond/etc
given a NULL-terminated string, s.
s[i] = '\0';
i++;
does not guarentee that s[i] is NULL terminated and thus string operations
could read off the end of the array.
https://bugzilla.gnome.org/show_bug.cgi?id=758039
gst_gl_shader_detach_unlocked already removes the list entry so attempting to
use the element to iterate to the next stage could read invalid data.
Based on patch by Vineeth TM <vineeth.tm@samsung.com>
https://bugzilla.gnome.org/show_bug.cgi?id=758039
Some drivers don't provide the compatibility definition and we need to provide
our own 'out vec4' variable to put the results of the fragment shader into.
https://bugzilla.gnome.org/show_bug.cgi?id=757938
Rectangular textures are unavailable in unextended
GLES2 #version 100 shaders.
Fixes
texture-target=rectangle ! glcolorconvert ! texture-target=2D
There's a couple of differences between GL3 and GLES2/GL
- varying -> in or out depending on the stage (vertex/fragment)
- attribute -> in
- filtered texture access is a single function, texture()
Make gst_gl_context_gen_shader/_compile_shader assume GST_GLSL_PROFILE_ES |
GST_GLSL_PROFILE_COMPATIBILITY as the profile. Without this, the shader compiler
doesn't inject the #version tag resulting in a compilation error on Mountain
Lion.
This is a workaround for old code using gst_gl_context_gen_shader. New code
should use the gst_glsl_stage_* API directly which allows the caller to
explicitly specify version/profile.
The ret variable may be uninitialized and so its contents were undefined and
the results were erratic (failing with glvideomixer, succeeding in other cases)
P.S. No idea why gcc/clang et al never picked up on this like they normally do
(probably due to some optimisation pass figuring out it's only set once...)
They are already defined in the forward decleration header and defining them
more than once will give an error with OSX's clang about typedef redefinition
being a C11 feature.
This was chosen over relying solely on the caps as glupload needs to propose an
allocation and set the texture target based on the output caps. Setting the
caps in the config is currently pointless as they are overwritten in a lot of
element's decide_allocation functions.
This provides a mechanism for the buffer pool to be configured for a certain
texture target when none has been configured.
Solved with a simple shader templating mechanism and string replacements
of the necessary sampler types/texture accesses and texture coordinate
mangling for rectangular and external-oes textures.
Add the various tokens/strings for the differnet texture types (2D, rect, oes)
Changes the GLmemory api to include the GstGLTextureTarget in all relevant
functions.
Update the relevant caps/templates for 2D only textures.
the USING_GLES2 includes all GLES3 contexts as well which does support
drawing to multiple buffers. Instead make or decision solely based on
whether glDrawBuffers is available or not.
e.g:
gstglcontext_egl.c:613:7: error: implicit declaration of function 'strcmp'
[-Werror=implicit-function-declaration]
if (strcmp (G_MODULE_SUFFIX, "so") == 0)
While technically, i is always 0 and *vertex_sources[i++] is equivalant
to (*vertex_sources)[i++]. Be future-proof in the case of code
moves/changes/etc.
CID 1327406
A GstGLShader is now simply a collection of stages that are
compiled and linked together into a program. The uniform/attribute
interface has remained the same.
1. So we get tracking inside GstElement properly when e.g. adding to a bin
2. Removes redundant code. Now only one place where
GstContext->GstGLDisplay/GstGLContext transformation occurs
3. Fixes a memory leak in the process
4. Make the retrieval of debug categories thread safe
These markers are visible in tools that record the GL function calls
such as apitrace, et al.
Makes it easier to match up GL draw commands with specific elements.
- glimagesink needs to be able to resize the viewport on aspect ratio
changes resulting from either caps changes or 3d output mode changes.
- Performing a glViewport outside the GstGLWindow::resize callback
will not have the winsys' stack of viewports required to correctly
place the output frame.
Provide a function to request a resize on the next draw event from the
winsys.
Also track size changes inside the base GstGLWindow class rather
than in each subclass.
https://bugzilla.gnome.org/show_bug.cgi?id=755111
when allocating memory. Fixes crashes with avdec_h265 in the AVX2
code path which requires 32-byte stride alignment, but the
GstAllocationParams only specified a 16-byte alignment.
https://bugzilla.gnome.org/show_bug.cgi?id=754120
HAVE_IOS is only defined for the build of this module so
attempting to use gstgl in iOS would result in incorrect GL
includes.
Use GST_GL_HAVE_PLATFORM_EAGL instead for choosing the iOS GL
header.
During allocation query, when this element is not passthrough, it must
relay the overlay compostion meta and it's parameters. Fortunatly, base
transform can do this for us.
https://bugzilla.gnome.org/show_bug.cgi?id=753850
GL_SHADING_LANGUAGE_VERSION was introduced since ES 2.0, but in some
android emulator doesn't support this feature. To prevent confusion for
developer, the error message need to be more clear.
https://bugzilla.gnome.org/show_bug.cgi?id=753905
Removes the redundant GL object creation/deletion on every
decide_allocation call which is being called for every caps change.
Thus reduces the required GL state changes on reconfigure events
which are being sent by glimagesink/xvimagesink
As we only expose the mapped portion of the frame into the GL
memory object (and not the original padding) we need to
re-calculate the size and offset.
Adding this private header to the list of sources. We don't want to make
this header public, but we need it in the list of sources otherwise it
won't be included in the tarball. This fixes make distcheck.
This regression was introduced by commit 1a6fe3db
Depending on the bytes order we will get BGRA (little) and ARGB (big)
from the composition overlay buffer while our GL code expects RGBA. Add
a fragment shader that do this conversion.
https://bugzilla.gnome.org/show_bug.cgi?id=752842
We can't know if the GstGLUpload type is initialized at this point already,
and thus our debug category might not be initialized yet... and cause an
assertion here.
As we don't print debug output for any of the other transform functions, let's
defer this problem for now.
The coordinate are relative to the texture dimension and not
the window dimension now. There is no need to pass the window
dimension or to update the overlay if the dimension changes.
https://bugzilla.gnome.org/show_bug.cgi?id=745107
They require to get_proc_address some functions through the
platform specific {glX,egl}GetProcAddress rather than the default
GL library symbol lookup.
nvidia drivers return the exact version in glGstString (GL_VERSION)
we request on creation so start with the highest known version and
work our way down.
The previous approach of traversing the other_context weak ref tree was
1. Less performant
2. Incorrect for context destruction removing a link in the tree
Example of 2:
c1 = context_create (NULL)
c2 = context_create (c1)
c3 = context_create (c2)
context_can_share (c1, c3) == TRUE
context_destroy (c2)
unref (c2)
context_can_share (c1, c3) returns FALSE when it should be TRUE!
This does not remove the restriction that context sharedness can only
be tracked between GstGLContext's.
This will deadlock if the main thread is the one who creates the GstGLContext.
All things we call from the main thread should be possible from any thread.
https://bugzilla.gnome.org/show_bug.cgi?id=751101
Add API for a helper object that can convert between different
stereoscopic video representations, and later do filtering
of multiple view streams.
https://bugzilla.gnome.org/show_bug.cgi?id=611157
Provides generic handling of GL buffer objects accessible using
the GL bind points (GL_ARRAY_BUFFER, GL_PIXEL_*_BUFFER).
Implementation based off the current GstGLMemory.
5697b6b89b causes us to possibly listen
on a toolkit provided Display connection. We thus could eat their
precious winsys events. Only listen if we need to
(!foreign_display or videooverlay).
