This is widely assumed, but is not guaranteed by Standard C, and is
known to be false on CHERI architectures (which have 64-bit sizes and
128-bit tagged pointers). Add a static assertion to ensure that GTK
will not build on platforms where this assumption does not hold.
As discussed on GNOME/gtk!7510, if GTK switches from gsize to uintptr_t
as its representation of the underlying bits in a pointer, GTK maintainers
would prefer that to be done project-wide so that it's done consistently,
after which this static assertion could be removed.
At the time of writing, GLib makes the same assumption (GNOME/glib#2842),
but GLib contributors are gradually removing it (mostly by replacing gsize
with uintptr_t where a pointer-sized quantity is needed). Finishing
that work in GLib would be a prerequisite for being able to make GTK
work on the affected platforms.
Signed-off-by: Simon McVittie <smcv@debian.org>
The modern incantation to get validation layers enabled is via
VK_INSTANCE_LAYERS=VK_LAYER_KHRONOS_validation
Vulkan has a bunch of environment variables to toggle stuff, let's use
those instead of doing our own.
This is a temporary solution to allow testing how well linear rendering
already works while refactoring code.
This will be removed once linear rendering is the default.
We prefer it over the old DESKTOP_STARTUP_ID environment variable if we
have it and it is valid.
We have to stash and unset XDG_ACTIVATION_TOKEN in addition to
DESKTOP_STARTUP_ID now as well. This makes sure that we don't call any
library functions which might rely on some environment variables. This
way unsetting the environment variables is safe and we can then
afterwards validate and print warnings.
This is useful for debugging offloading without having to rely
on gstreamer giving us dmabufs. To use it, set
GDK_DEBUG=force-offload
in the environment.
The ngl renderer has good support for fractional scaling, so we
can enable this by default now.
If you are using the gl renderer, you can disable fractional
scaling with the
GDK_DEBUG=gl-no-fractional
environment variable.
Add a new debug flag for dmabuf-related information,
and use it in gdkdmabuftexture.c.
This will let us separate out dmabuf debug spew from
opengl debug spew.
Fractional scaling with the GL renderer is
experimental for now, so we disable it unless
GDK_DEBUG=gl-fractional is set.
This will give us time to work out the kinks.
Introduce GDK_DISPLAY_DEBUG() and GDK_DEBUG() and
the helper function gdk_debug_message(). This is
meant to clean up the mess of our current debug
statements which wildly mix g_message, g_print
and g_printerr.
Add gdk_gl_context_is_api_allowed() for backends and make them use it.
Finally, have them return the final API as the return value (or 0 on
error).
And then use that api instead of a use_es boolean flag.
Fixes#4221
The term "hdr" is so overloaded, we shouldn't use them anywhere, except
from maybe describing all of this work in blog posts and other marketing
materials.
So do renames:
* hdr => high_depth
* request_hdr => prefers_high_depth
This more accurately describes what is going on.
Forces request_hdr = TRUE for all requests.
Backends should also use this when choosing whether to honor HDR
requests for low quality compositors - as long as the compositor
pretends to support HDR, shovel HDR at it.
We have a global GdkGLBackendType now, just set it.
This way, using the variable forces the backend type, and we don't need
special code handling the env vars in the backends.
It also means setting the env var will now "work" on GDK backends that
don't even support that GL backend and simualte another GDK backend
having registered that GL backend already. So you can run
GDK_DEBUG=gl-wgl gtk4-demo
on test what Wayland will do when WGL is in use.
This way, one can force using WGL on Windows even if EGL support was
enabled. Also update the help text for gl-egl as it will apply for
Windows, albeit a bit later.
We try EGL first, but are very picky about what we accept.
If that fails, we try to go with GLX instead.
And if that also fails, we try EGL again, but this time accept anything.
The idea here is that EGL is the preferred method going forward, but GLX is
the tried and tested method that we know works. So if we detect issues with
EGL, we want to avoid using it in favor of GLX.
Also add a GDK_DEBUG=gl-egl option to force EGL at all costs and not try
GLX.
