Since #5602, SDL is intended to have the same ABI across the whole
major-version 2 cycle, so we should not check that the minor version
matches the one that was used to compile an application.
There are two checks that could make sense here.
The first check is that the major version matches the expected major
version. This is usually unnecessary and is not usually done (if we're
calling into the wrong library we'll likely crash anyway), but since we
have the information, we might as well continue to use it.
The second check is whether the version provided by the caller is
equal to or greater than a threshold version at which additional fields
were added to the struct. If it is, we should populate those fields;
if it is not, then we cannot. This is only useful on platforms where
additional fields have genuinely been added during the lifetime of
SDL 2, like Windows and DirectFB (but not X11).
This commit changes the first check to be consistent about only looking
at the minor version, while leaving the second check using SDL_VERSIONNUM
(which will be removed or widened in SDL 3, but it's fine for now).
Resolves: https://github.com/libsdl-org/SDL/issues/5711
Fixes: cd7c2f1 "Switch versioning scheme to be the same as GLib and Flatpak"
Signed-off-by: Simon McVittie <smcv@collabora.com>
The two are only ever called together, and combining them makes it possible
to eliminate redundant symbol loading and redundant attempts to connect
to a display server.
Vivante drivers use the VK_KHR_display extension for rendering directly
to the frame buffer. This patch adds support to the video driver for
Vulkan rendering using that method.
- Add an utility function SDL_Vulkan_Display_CreateSurface that creates
a surface using this extension. The display to use (if there are
multiple) can be overridden using the environment variable
"SDL_VULKAN_DISPLAY".
- Use this function in a new compilation unit SDL_vivantevideo.c,
which implements the SDL_VIDEO_VULKAN methods of the driver structure.
Manuel
The attached patch adds support for KMS/DRM context graphics.
It builds with no problem on X86_64 GNU/Linux systems, provided the needed libraries are present, and on ARM GNU/Linux systems that have KMS/DRM support and a GLES2 implementation.
Tested on Raspberry Pi: KMS/DRM is what the Raspberry Pi will use as default in the near future, once the propietary DispmanX API by Broadcom is overtaken by open graphics stack, it's possible to boot current Raspbian system in KMS mode by adding "dtoverlay=vc4-kms-v3d" to config.txt on Raspbian's boot partition.
X86 systems use KMS right away in every current GNU/Linux system.
Simple build instructions:
$./autogen.sh
$./configure --enable-video-kmsdrm
$make
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
Simon McVittie
Sam Lantinga
M Stoeckl
Wladimir J. van der Laan
Philipp Wiesemann