* dos: Some initial work.
* dos: Turn off buffer on stdio SDL_IOStreams.
Seeking breaks otherwise. We might be able to just fflush() before or seeking
instead?
* dos: Audio implementation using the Sound Blaster 16.
* dos: remove audio Pump interface.
Turns out DosBox-X was having trouble with the Sound Blaster or something;
standard DosBox works correctly directly from the interrupt handler, and
without doubling the buffer size.
* dos: just dump and restore the stdio buffer when seeking.
This is MUCH faster than just leaving buffering disabled, and also works
around getting bogus reads after an fseek. SDL_LoadWAV on test/sample.wav
no longer takes several seconds to finish, and comes up with the correct
data.
I wonder if we're triggering this in LoadWAV because we're malloc'ing data
between seeks/reads, and it's causing the djgpp transfer buffer to change. Or
maybe the Fat DS trick is confusing it? I don't know, I haven't had time to
debug it, it might just be a legit libc bug in djgpp too, for all I know.
* dos: Protect audio device "thread" iterations when streams are locked.
This uses an old trick we used in SDL 1.2 for MacOS Classic, which did its
audio callback in a hardware interrupt. If the audio is locked when the
interrupt fires, make a note of it and return immediately. When the lock is
released, if the interrupt has been fired, run the audio device iteration
right then.
Since there isn't a big device lock in SDL3 (available to the app, at least),
this keeps a counter of when any SDL_AudioStream is locked, which is probably
good enough.
* dos: Implemented initial video subsystem.
This uses VESA interfaces to manage the display and works with the software
renderer.
Events aren't hooked up yet, so prepare to close DosBox on each run. :)
* dos: Whoops, forgot to add these to revision control. Core and Main support.
* dos: Wired up basic filesystem support.
This gets most of the rendering examples, which use SDL_GetBasePath() to
find textures to load, working.
* dos: Fixed compiler warning.
* dos: Initial mouse support!
* dos: Move interrupt hooking code into core/dos.
* dos: Initial keyboard support!
* dos: Use a simple ring buffer for keyboard events.
Of course Quake 1 solved this better, haha. It's smart: less memory, dirt
simple, and you don't even have to worry about synchronizing with the
interrupt handler, because it's safe for both sides no matter when an
interrupt fires.
* ci: add djgpp job
[sdl-ci-filter djgpp]
[sdl-ci-artifacts]
* dos: Fix build issues after rebase onto current main
- SDL_runapp.c: Add SDL_PLATFORM_DOS to the exclusion list so the
generic
SDL_RunApp() is disabled when the DOS-specific one is compiled.
- SDL.c: Exclude SDL_Gtk_Quit() on DOS. DJGPP defines __unix__ which
sets
SDL_PLATFORM_UNIX, but DOS has no GTK/display server. The GTK source
is not compiled (CMake UNIX is false for DOS) so this was a link
error.
- sdlplatform.cmake: Add DOS case to SDL_DetectCMakePlatform so the
platform is properly detected from CMAKE_SYSTEM_NAME=DOS.
- i586-pc-msdosdjgpp.cmake: Add i386-pc-msdosdjgpp-gcc as a fallback
compiler name, since some DJGPP toolchain builds use the i386 prefix.
* Add 8-bit palette support to DOS VESA driver
* Add VBE page-flipping, state restore, and robust keyboard handling
- Implement double-buffered page-flipping for VBE modes with >1 image
page
- Save and restore full VBE state on video init/quit for clean mode
switching
- Improve DOS keyboard handling: support extended scancodes and Pause
key
- Lock ISR code/data to prevent page faults during interrupts
- Always vsync when blitting in single-buffered modes to reduce tearing
* Refactor Sound Blaster audio mixing to main loop
Move audio mixing out of IRQ handler to main loop for improved
stability and to avoid reentrancy issues. Add SDL_DOS_PumpAudio
function, update DMA buffer handling, and adjust sample rate to 22050
Hz.
Silence stale DMA buffer halves to prevent stutter during load.
* Add DOS timer support and update build config
* Add support for pre-SB16 8-bit mono Sound Blaster audio
Detect SB version and select 8-bit mono or 16-bit stereo mode.
Handle DMA and DSP setup for both SB16 and pre-SB16 hardware.
Add FORCE_SB_8BIT option for testing in DOSBox.
* Add SB Pro stereo support and simplify IRQ handler
* Add DOS joystick driver support
* Improve DOS hardware handling and clarify memory allocation
- Poll Sound Blaster DSP status instead of fixed delay after speaker-on
- Clarify DPMI conventional memory is always locked; update comments
- Document and justify DMA memory allocation strategy
- Free IRET wrapper after restoring interrupt vector to avoid leaks
- Throttle joystick axis polling to ~60 Hz to reduce BIOS timing loop
cost
- Always poll joystick buttons directly for responsiveness
* Query and use mouse sensitivity from INT 33h function 0x1B
* Add support for VESA banked framebuffer modes
Implement banked framebuffer access for VBE 1.2+ modes without LFB.
Detect and initialize banked modes, copy framebuffer data using bank
switching, and blank the framebuffer on mode set. Page-flipping is
disabled in banked mode.
* Add optional vsync to page flipping in DOS VESA driver
* Add cooperative threading support for DOS platform
* Move SoundBlaster audio mixing to SDL audio thread
* Fix DOS platform comments and workarounds for DJGPP support
* Fix SoundBlaster IRQ handling and DMA setup for DOS
- Pass IRQ number to DOS_EndOfInterrupt and handle slave PIC EOI
- Validate DMA channel from BLASTER variable
- Correct DMA page register selection for SB16
- Improve BLASTER variable parsing and error messages
- Unmask/mask IRQs on correct PIC in DOS_HookInterrupt
- Rename SDL_dosjoystick.c to SDL_sysjoystick.c
- Include SDL_main_callbacks.h in SDL_sysmain_runapp.c
- Add include guard to SDL_systhread_c.h
* Add DOS platform options and preseed cache for DJGPP
Disable unsupported SDL features when building for DOS. Add
PreseedDOSCache.cmake to pre-populate CMake cache variables for DJGPP.
* cmake: use a 8.3 naming scheme for tests on DOS
* Apply code style
* Update include/SDL3/SDL_platform_defines.h
Co-authored-by: Anonymous Maarten <madebr@users.noreply.github.com>
* Code review clean up
- Split DOS VESA mode-setting into its own file
- Replace magic numbers with named constants
- Update copyright dates to 2026
- Substract time taken by other threads form delays
* Fix DOS bugs and improve compatibility
- Disable fseeko64 for DJGPP due to broken implementation
- Refactor DOS timer delay to always yield and avoid busy-waiting
- Fix animated cursor rendering in DOS VESA backend
- Always set display mode when creating DOS VESA window
- Work around DJGPP allowing invalid file access in testfile.c
- Bump max threads to 16
- Apply workarounds for threading tests
* Add DOS platform documentation and fix a few issues
- Fix fullscreen default resolution
- Improve best mode matching
- Fix builds on GCC older than 7.0
- Fix text input events
* Fix keyboard mapping of "*"
* Fix running, and existing, under PCem
* Apply suggestions from code review
Co-authored-by: Cameron Cawley <ccawley2011@gmail.com>
* Pre-mix audio in ring buffer and copy to DMA via IRQ thread
* Video fixes and optimizations
* DOS: Fix Intel 740 and VGA compatability
* DOS: Update readme
* DOS: Fix thread ID, get GPU name
* DOS: Cap mouse range
* DOS: Map test resources to 8.3 names
* DOS: Skip unsupported WM color modes
* Fix "windowed" resolution selection
* DOS: Hide INDEX8 modes behind SDL_DOS_ALLOW_INDEX8_MODES
* Remove SDL_HINT_DOS_ALLOW_INDEX8_MODES and order modes logically
* Don't convert cursor if dest is not INDEX8
---------
Co-authored-by: Ryan C. Gordon <icculus@icculus.org>
Co-authored-by: Anonymous Maarten <anonymous.maarten@gmail.com>
Co-authored-by: Cameron Cawley <ccawley2011@gmail.com>
Co-authored-by: Gleb Mazovetskiy <glex.spb@gmail.com>
Co-authored-by: Jay Petacat <jay@jayschwa.net>
Tested-by: Cameron Cawley <ccawley2011@gmail.com>
Scales pointer coordinates where needed to fix the following tests when run with the --high-pixel-density flag:
- testaudio
- testaudiostreamdynamicresample
- testhittesting
- testintersections
- testmanymouse
- testoverlay
- testwm
We require stdbool.h in the build environment, so we might as well use the plain bool type.
If your environment doesn't have stdbool.h, this simple replacement will suffice:
typedef signed char bool;
It was intended to make the API easier to use, but various automatic garbage collection all had flaws, and making the application periodically clean up temporary memory added cognitive load to using the API, and in many cases was it was difficult to restructure threaded code to handle this.
So, we're largely going back to the original system, where the API returns allocated results and you free them.
In addition, to solve the problems we originally wanted temporary memory for:
* Short strings with a finite count, like device names, get stored in a per-thread string pool.
* Events continue to use temporary memory internally, which is cleaned up on the next event processing cycle.
These are integer values internally, but the API has been changed to make it easier to mix other render code with querying those values.
Fixes https://github.com/libsdl-org/SDL/issues/7519
We have gotten feedback that abstracting the coordinate system based on the display scale is unexpected and it is difficult to adapt existing applications to the proposed API.
The new approach is to provide the coordinate systems that people expect, but provide additional information that will help applications properly handle high DPI situations.
The concepts needed for high DPI support are documented in README-highdpi.md. An example of automatically adapting the content to display scale changes can be found in SDL_test_common.c, where auto_scale_content is checked.
Also, the SDL_WINDOW_ALLOW_HIGHDPI window flag has been replaced by the SDL_HINT_VIDEO_ENABLE_HIGH_PIXEL_DENSITY hint.
Fixes https://github.com/libsdl-org/SDL/issues/7709
This fixes rounding errors with coordinate scaling and gives more flexibility in the presentation, as well as making it easy to maintain device independent resolution as windows move between different pixel density displays.
By default when a renderer is created, it will match the window size so window coordinates and render coordinates are 1-1.
Mouse and touch events are no longer filtered to change their coordinates, instead you can call SDL_ConvertEventToRenderCoordinates() to explicitly map event coordinates into the rendering viewport.
SDL_RenderWindowToLogical() and SDL_RenderLogicalToWindow() have been renamed SDL_RenderCoordinatesFromWindow() and SDL_RenderCoordinatesToWindow() and take floating point coordinates in both directions.
The viewport, clipping state, and scale for render targets are now persistent and will remain set whenever they are active.
Rather than iterating over display modes using an index, there is a new function SDL_GetFullscreenDisplayModes() to get the list of available fullscreen modes on a display.
{
SDL_DisplayID display = SDL_GetPrimaryDisplay();
int num_modes = 0;
SDL_DisplayMode **modes = SDL_GetFullscreenDisplayModes(display, &num_modes);
if (modes) {
for (i = 0; i < num_modes; ++i) {
SDL_DisplayMode *mode = modes[i];
SDL_Log("Display %" SDL_PRIu32 " mode %d: %dx%d@%gHz, %d%% scale\n",
display, i, mode->pixel_w, mode->pixel_h, mode->refresh_rate, (int)(mode->display_scale * 100.0f));
}
SDL_free(modes);
}
}
SDL_GetDesktopDisplayMode() and SDL_GetCurrentDisplayMode() return pointers to display modes rather than filling in application memory.
Windows now have an explicit fullscreen mode that is set, using SDL_SetWindowFullscreenMode(). The fullscreen mode for a window can be queried with SDL_GetWindowFullscreenMode(), which returns a pointer to the mode, or NULL if the window will be fullscreen desktop. SDL_SetWindowFullscreen() just takes a boolean value, setting the correct fullscreen state based on the selected mode.
SDL_DisplayMode now includes the pixel size, the screen size and the relationship between the two. For example, a 4K display at 200% scale could have a pixel size of 3840x2160, a screen size of 1920x1080, and a display scale of 2.0.
