Martin Fiedler
To be precise, this is about *desktop OpenGL* on X11. For OpenGL ES, EGL is already used (as it's the only way to get an OpenGL ES context), as Sylvain noted above.
To shine some light on why this is needed:
In 99% of all cases, using GLX on X11 is fine, even though it's effectively deprecated in favor of EGL [1]. However, there's at least one use case that *requires* the OpenGL context being created with EGL instead of GLX, and that's DRM_PRIME interoperability: The function glEGLImageTargetTexture2DOES simply doesn't work with GLX. (Currently, Mesa actually crashes when trying that.)
Some example code:
https://gist.github.com/kajott/d1b29c613be30893c855621edd1f212e
Runs on Intel and open-source AMD drivers just fine (others unconfirmed), but with #define USE_EGL 0 (i.e. forcing it to GLX), it crashes. The same happens when using SDL for window and context creation.
The good news is that most of the pieces for EGL support on X11 are already in place: SDL_egl.c is pretty complete (and used for desktop OpenGL on Wayland, for example), and SDL_x11opengl.c has the aforementioned OpenGL-ES-on-EGL support. However, when it comes to desktop OpenGL, it's hardcoded to fall back to GLX.
I'm not advocating to make EGL the default for desktop OpenGL on X11; don't fix what ain't broken. But something like an SDL_HINT_VIDEO_X11_FORCE_EGL would be very appreciated to make use cases like the above work with SDL.
[1] source: Eric Anholt, major Linux graphics stack developer, 7 years ago already - see last paragraph of https://www.phoronix.com/scan.php?page=news_item&px=MTE3MTI
Aaron Barany
Add SDL_HINT_VIDEO_EXTERNAL_CONTEXT hint to notify SDL that the graphics context is external. This disables the automatic context save/restore behavior on Android and avoids using OpenGL by default when SDL_WINDOW_VUKLAN isn't set.
When the application wishes to manage the OpenGL contexts on Android, this avoids cases where SDL unbinds the context and creates new contexts, which can interfere with the application's operation.
When using Vulkan and Metal renderer implementations, this avoids SDL forcing OpenGL to be enabled on certain platforms. While using the SDL_WINDOW_VULKAN flag can be used to achieve the same thing, it also causes Vulkan to be loaded. If the application uses Vulkan directly, this is not necessary, and fails window creation when using Metal due to Vulkan not being present. (assuming MoltenVK isn't installed)
It causes the HIDAPI devices to always be opened on enumeration, which causes crashes in the Windows drivers when multiple applications are reading and writing at the same time. We can revisit this after 2.0.10 release.
Simon Hug
Attached is a minor cleanup patch. It changes the option name of one hint to something better, puts one or two more checks in, and adds explicit casting where warnings could appear otherwise.
I hope the naming of the hints and their options is acceptable. It would be kind of awkward to change them after they get released with an official SDL version.
Simon Hug
I had a look at this and made some additions to SDL_wave.c.
The attached patch adds many checks and error messages. For some reason I also added A-law and ?-law decoders. Forgot exactly why... but hey, they're small.
The WAVE format is seriously underspecified (at least by the documents that are publicly available on the internet) and it's a shame Microsoft never put something better out there. The language used in them is so loose at times, it's not surprising the encoders and decoders behave very differently. The Windows Media Player doesn't even support MS ADPCM correctly.
The patch also adds some hints to make the decoder more strict at the cost of compatibility with weird WAVE files.
I still think it needs a bit of cleaning up (Not happy with the MultiplySize function. Don't like the name and other SDL code may want to use something like this too.) and some duplicated code may be folded together. It does work in this state and I have thrown all kinds of WAVE files at it. The AFL files also pass with it and some even play (obviously just noise). Crafty little fuzzer.
Any critique would be welcome. I have a fork of SDL with a audio-loadwav branch over here if someone wants to use the commenting feature of Bitbucket:
https://bitbucket.org/ChliHug/SDL
I also cobbled some Lua scripts together to create WAVE test files:
https://bitbucket.org/ChliHug/gendat
java layer runs as if separate mouse and touch was 1,
Use SDL_HINT_MOUSE_TOUCH_EVENTS and SDL_HINT_TOUCH_MOUSE_EVENTS
for generating synthetic touch/mouse events
Note that a single USB device is responsible for all 4 joysticks, so a large
rewrite of the DeviceDriver functions was necessary to allow a single device to
produce multiple joysticks.
Callum McGing
This patch allows the user to disable the behaviour that blocks the compositor through a new hint: SDL_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR. This allows tools or other windowed applications to behave properly under KWin.
This variable can be set to the following values:
"0" - The indicator bar is not hidden (default for windowed applications)
"1" - The indicator bar is hidden and is shown when the screen is touched (useful for movie playback applications)
"2" - The indicator bar is dim and the first swipe makes it visible and the second swipe performs the "home" action (default for fullscreen applications)
Dominik Reichardt
As discussed in 2012 the iOS onscreen keyboard hides when you hit RETURN (see https://discourse.libsdl.org/t/on-screen-keyboard-change/19216).
IMO this is a bad idea to not be able to influence this behavior and just recently this was fixed for Android by adding the hint SDL_HINT_ANDROID_RETURN_HIDES_IME in changeset 11768 6ce3bb5e38a5.
Alexey
Seems to be a missing functionality. I want to set an icon from RC file. I cant pass MAKEINTRESOURCE(X) string to SDL_RegisterApp() cause string returned by MAKEINTRESOURCE string is not actually a string and SDL_strlen will crash. Moreover LoadImage seems to be loading wrong icon size. LoadIcon seems to be fine.
It's easier for Visual Studio users that want this information to turn it on
or live without it, than it is to explain why every debugger that isn't Visual
Studio crashes out here. Eventually SetThreadDescription() will be the thing
everyone uses anyhow.
Fixes Bugzilla #3645.
(and several others).
