Unify the X11 and Wayland EGL contexts.
This is a bit ugly to implement, because I don't want to create an
interface and I can't make them inherit from the same object, because
one needs to inherit from X11GLContext and the other from
WaylandGLContext.
So we have to put the code in GdkGLContext and make sure non-EGL
contexts can't accidentally run it. This is rather easy because we can
just check for priv->egl_context != NULL.
Creative people managed to create an X11 display and a Wayland display
at once, thereby getting EGL and GLX involved in a fight to the death
over the ownership of the glFoo() symbolspace.
A way to force such a fight with available tools here is (on Wayland)
running something like:
GTK_INSPECTOR_DISPLAY=:1 GTK_DEBUG=interactive gtk4-demo
Related: xdg-desktop-portal-gnome#5
Now that we have the display's context to hook into, we can use it to
construct other GL contexts and don't need a GdkSurface vfunc anymore.
This has the added benefit that backends can have different GdkGLContext
classes on the display and get new GLContexts generated from them, so
we get multiple GL backend support per GDK backend for free.
I originally wanted to make this a vfunc on GdkGLContextClass, but
it turns out all the abckends would just call g_object_new() anyway.
Instead of
Display::make_gl_context_current()
we now have
GLContext::clear_current()
GLContext::make_current()
This fits better with the backends (we can actually implement
clearCurrent on macOS now) and makes it easier to implement different GL
backends for backends (like EGL/GLX on X11).
We also pass a surfaceless boolean to make_current() so the calling code
can decide if a surface needs to be bound or not, because the backends
were all doing whatever, which was very counterproductive.
... or more exactly: Only use paint contexts with
gdk_cairo_draw_from_gl().
Instead of paint contexts being the only contexts who call swapBuffer(),
any context can be used for this, when it's used with
begin_frame()/end_frame().
This removes 2 features:
1. We no longer need a big sharing hierarchy. All contexts are now
shared with gdk_display_get_gl_context().
2. There is no longer a difference between attached and non-attached
contexts. All contexts work the same way.
Do not treat the context as already current when the value
of context::in-frame changes.
This is so we can bind to EGL_NO_SURFACE if context::in-frame == false
and to context::surface if context::in-frame == true.
This allows getting rid of the attached property in future commits.
Remove a boatload of "or %NULL" from nullable parameters
and return values. gi-docgen generates suitable text from
the annotation that we don't need to duplicate.
This adds a few missing nullable annotations too.
We do not need to translate this on the CPU when we can instead push it
to the GPU in the same format and allow it to swizzle.
This fixes a huge number of memory allocations found while uploading the
GTK animation in widget-factory.
GLDEBUGPROC callback is defined with APIENTRY which is a windows
specific calling convention. That macro expands to nothing when building
on other platforms.
Fixes: #3268.
Go back to installing our debug message callback
unconditionally if G_ENABLE_CONSISTENCY_CHECKS is
defined, and allow opting into it using GDK_DEBUG=gl-debug
otherwise.
Always install the debug message callback when we can
and GDK_DEBUG=gl-debug is specified. Previously, we
were only installing the callback when the build was
a non-optimized debug build.
The gdk-pixbuf non-rgba format can be directly uploaded without
conversion.
The rgba format needs alpha premultiplication though, which is not
supported by GL during upload.
GLES doesn't support the GL_BGRA + GL_UNSIGNED_INT_24_8 hack that
we use on desktop OpenGL to upload textures directly in the cairo
pixel format. This adds the required conversions to all the places
that currently need it.
We also add a data_format to the internal gdk_gl_context_upload_texture()
function to make it clearer what the format are. Currently it is always
the cairo image surface format, but eventually we want to support other
formats so that we can avoid some of the unnecessary conversions we do.
Also, the current gdk_gl_context_upload_texture() code always converts
to a cairo format and uploads that like we did before. Later commits
will allow this to use other upload formats that gl supports to avoid
conversions.
gdk_gl_context_has_framebuffer_blit() and gdk_gl_context_has_frame_terminator()
were only used by by GDK/Win32, and they do not provide performance advantages
in GTK master, so clean up the code a bit by dropping them.
We need to use GL_BGRA instead of GL_RGBA when doing glReadPixels() on
EGL on Windows (ANGLE) so that the red and blue bits won't be displayed
inverted.
Also fix the logic where we determine whether to bit blit or redraw
everything.
This is for adding a EGL-based renderer which is done via the ANGLE
project, which translate EGL calls to Direct3D 9/11. This is done as a
possible solution to issue #105, especially for cases where the needed
full GL extensions to map OpenGL to Direct3D is unavailable or
unreliable, or when the OpenGL implementation from the graphics drivers
are problematic.
To enable this, do the following:
-Build ANGLE and ensure the ANGLE libEGL.dll and libGLESv2.dll are
available. A sufficiently-recent ANGLE is needed for things to
work correctly--note that the copy of ANGLE that is included in
qtbase-5.10.1 is sufficient. ANGLE is licensed under a BSD 3-clause
license.
-Build libepoxy on Windows with EGL support enabled.
-Currently, prior to running GTK+ programs, the GDK_DEBUG envvar needs
to be set with gl-gles as at least one of the flags.
Known issues:
-Only OpenGL ES 3 is supported, ANGLE's ES 2 does not support the needed
extensions, notably GL_OES_vertex_array_object, but its ES 3 support is
sufficient.
-There is no autodetection or fallback mechanism to enable using
EGL/Angle automatically yet. There are no plans to do this in this
commit.
For a given OpenGL context, macOS in particular does not support enumeration / detection of OpenGL features that have been promoted to core OpenGL functionality. It is possible other drivers are the same. This change assumes support for GL_ARB_texture_non_power_of_two with OpenGL 2.0+, GL_ARB_texture_rectangle with OpenGL 3.1+ and GL_EXT_framebuffer_blit with OpenGL 3.0+. I failed to find definitive information on whether GL_GREMEDY_frame_terminator has been promoted to OpenGL core, or whether GL_ANGLE_framebuffer_blit or GL_EXT_unpack_subimage have been promoted to core in OpenGL ES. This change results in a significant GtkGLArea performance boost on macOS.
Closes#2428
We need to store the region *before* adding our own damage area, because
we want to only store the changes of this frame, not the whole history.
So do it in the same place Vulkan does it.
Fixes#1900
We used to pass 2 regions to GdkDrawCotnext.end_frame() but code was
confusing what they meant. So we now don't do that anymore and only pass
the region that matters: The frame region.
As they require a draw context and the draw context is already bound to
the surface, it makes much more sense and reduces abiguity by moving
these APIs to the draw context.
As a side effect, we simplify GdkSurface APIs to a point where
GdkSurface now does not concern itself with drawing anymore at all,
apart from being the object that creates draw contexts.
