SDL_strcasecmp (even when calling into a C runtime) does not work with
Unicode chars, and depending on the user's locale, might not work with
even basic ASCII strings.
This implements the function from scratch, using "case-folding,"
which is a more robust method that deals with various languages. It
involves a hashtable of a few hundred codepoints that are "uppercase" and
how to map them to lowercase equivalents (possibly increasing the size of
the string in the process). The vast majority of human languages (and
Unicode) do not have letters with different cases, but still, this static
table takes about 10 kilobytes on a 64-bit machine.
Even this will fail in one known case: the Turkish 'i' folds differently
if you're writing in Turkish vs other languages. Generally this is seen as
unfortunate collateral damage in cases where you can't specify the language
in use.
In addition to case-folding the codepoints, the new functions also know how
to decode the various formats to turn them into codepoints in the first
place, instead of blindly stepping by one byte (or one wchar_t) per
character.
Also included is casefolding.txt from the Unicode Consortium and a perl
script to generate the hashtable from that text file, so we can trivially
update this if new languages are added in the future.
A simple test using the new function:
```c
#include <SDL3/SDL.h>
int main(void)
{
const char *a = "α ε η";
const char *b = "Α Ε Η";
SDL_Log(" strcasecmp(\"%s\", \"%s\") == %d\n", a, b, strcasecmp(a, b));
SDL_Log("SDL_strcasecmp(\"%s\", \"%s\") == %d\n", a, b, SDL_strcasecmp(a, b));
return 0;
}
```
Produces:
```
INFO: strcasecmp("α ε η", "Α Ε Η") == 32
INFO: SDL_strcasecmp("α ε η", "Α Ε Η") == 0
```
glibc strcasecmp() fails to compare a Greek lowercase string to its uppercase
equivalent, even with a UTF-8 locale, but SDL_strcasecmp() works.
Other SDL_stdinc.h functions are changed to be more consistent, which is to
say they now ignore any C runtime and often dictate that only English-based
low-ASCII works with them.
Fixes Issue #9313.
- SDL_RWops is now an opaque struct.
- SDL_AllocRW is gone. If an app is creating a custom RWops, they pass the
function pointers to SDL_CreateRW(), which are stored internally.
- SDL_RWclose is gone, there is only SDL_DestroyRW(), which calls the
implementation's `->close` method before freeing other things.
- There is only one path to create and use RWops now, so we don't have to
worry about whether `->close` will call SDL_DestroyRW, or if this will
risk any Properties not being released, etc.
- SDL_RWFrom* still works as expected, for getting a RWops without having
to supply your own implementation. Objects from these functions are also
destroyed with SDL_DestroyRW.
- Lots of other cleanup and SDL3ization of the library code.
Eventually we can re-add a fast path for that data down to the individual renderers. Setting color scale would still require converting to float, and most hardware accelerated renderers prefer to consume colors as float, so this requires some thought and performance testing.
Fixes https://github.com/libsdl-org/SDL/issues/9009
Add a mode that forces Wayland windows to output with scaling that forces 1:1 pixel mapping.
This is intended to allow legacy applications to be displayed without desktop scaling being applied, and may have issues with some display configurations, as this forces the window to behave in a way that Wayland desktops were not designed to accommodate (rounding errors can result from certain combinations of window/scale values, the window may be unusably small, jump in size at times, or appear to be larger than the desktop space, and cursor precision may be reduced).
Windows flagged as DPI-aware are not affected by this.
The automated video test suite passes with the hint turned on.
Specifically, SDL_WinRTRunApp, SDL_UIKitRunApp, and SDL_GDKRunApp macros were
removed, as likely unnecessary to SDL3 users. A note was added to the
migration doc about how to roll replacements. These are not going into
SDL_oldnames.h.
Fixes#8245.
Modern C runtimes have well optimized memset and memcpy, so use those instead of dispatching into SDL's versions. In addition, some compilers can analyze memset and memcpy calls and directly turn them into optimized assembly.
Add the ability to import and wrap external surfaces from external toolkits such as Qt and GTK.
Wayland surfaces and windows are more intrinsically tied to the client library than other windowing systems, so it is necessary to provide a way to initialize SDL with an existing wl_display object, which needs to be set prior to video system initialization, or export the internal SDL wl_display object for use by external applications or toolkits. For this, the global property SDL_PROPERTY_GLOBAL_VIDEO_WAYLAND_WL_DISPLAY_POINTER is used.
A Wayland example was added to testnative, and a basic example of Qt 6 interoperation is provided in the Wayland readme to demonstrate the use of external windows with both SDL owning the wl_display, and an external toolkit owning it.
Allow for the creation of SDL windows with a roleless surface that applications can use for their own purposes, such as with a windowing protocol other than XDG toplevel.
The property `wayland.surface_role_custom` will create a window with a surface that SDL can render to and handles input for, but is not associated with a toplevel window, so applications can use it for their own, custom purposes (e.g. wlr_layer_shell).
A test/minimal example is included in tests/testwaylandcustom.c
Wayland will be increasingly encountered going forward and needs to be handled by applications requesting window handles to initialize the Vulkan WSI and such, so include it in the migration example to reflect current best practices.
Petar Popovic
Sam Lantinga
Ryan C. Gordon
Mirko Galimberti
Cameron Gutman
SDL Wiki Bot
Susko3
Anonymous Maarten
Frank Praznik
Anonymous Maarten
Edoardo Lolletti
chalonverse