Go to file
Ryan C. Gordon e2ec1eb12e audio: converting int32 to/from float shouldn't use doubles.
The concern is that a massive int sample, like 0x7FFFFFFF, won't fit in a
float32, which doesn't have enough bits to hold a whole number this large,
just to divide it to get a value between 0 and 1.
Previously we would convert to double, to get more bits, do the division, and
cast back to a float, but this is expensive.

Casting to double is more accurate, but it's 2x to 3x slower. Shifting out
the least significant byte of an int32, so it'll definitely fit in a float,
and dividing by 0x7FFFFF is still accurate to about 5 decimal places, and the
difference doesn't appear to be perceptable.
2018-05-15 01:04:11 -04:00
VisualC Merged latest changes from Steam Link app 2018-05-18 13:09:30 -07:00
VisualC-WinRT Windows Phone 8.0 is no longer supported 2018-02-09 08:03:03 -08:00
Xcode Fixed bug 4088 - Fix Metal link errors with test programs in SDLTest.xcodeproj 2018-02-20 09:04:31 -08:00
Xcode-iOS Added missing file to tvOS build 2018-02-24 08:40:30 -08:00
acinclude Fixed bug 3481 - Configure fails to detect dynamic library support on powerpc64le 2016-11-06 20:26:48 -08:00
android-project Reimplemented Android cursor API support using reflection so it builds with older SDKs 2018-03-16 11:08:53 -07:00
android-project-ant Added the old ant Android build project structure 2017-10-28 12:11:25 -07:00
build-scripts Fixed bug 4065 - SDL_wave.c fail to compile in armeabi with ndk r16b 2018-01-27 12:05:26 -08:00
cmake Fixed bug 4027 - CheckLibSampleRate macro in sdlchecks.cmake never defines HAVE_LIBSAMPLERATE{,_SHARED}, so they're always reported as disabled by MESSAGE_TESTED_OPTION macro in macros.cmake 2018-02-13 13:25:59 -08:00
debian Updated copyright for 2018 2018-01-03 10:03:25 -08:00
docs On Android show the system UI when an SDL window is windowed, hide the system UI when it's fullscreen, like we do on iOS. 2018-02-11 18:23:37 -08:00
include cpuinfo: Added SDL_HasAVX512F(). 2018-05-21 11:35:42 -04:00
src audio: converting int32 to/from float shouldn't use doubles. 2018-05-15 01:04:11 -04:00
test cpuinfo: Added SDL_HasAVX512F(). 2018-05-21 11:35:42 -04:00
visualtest Renaming of guard header names to quiet -Wreserved-id-macro 2017-08-28 00:22:23 -07:00
.hgignore Updated SDL's YUV support, many thanks to Adrien Descamps 2017-11-12 22:51:12 -08:00
Android.mk Added Android build script for SDL 2017-12-16 10:40:41 -08:00
BUGS.txt BUGS.txt: Changed mailing list link to discourse.libsdl.org. 2017-04-01 00:05:25 -04:00
CMakeLists.txt Fixed bug 4135 - Broken symlink libSDL2.so since rev11940 2018-04-15 09:37:51 -07:00
COPYING.txt Updated copyright for 2018 2018-01-03 10:03:25 -08:00
CREDITS.txt Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00
INSTALL.txt More HTTPS doc tweaks. 2017-02-16 16:59:07 -05:00
Makefile.in vulkan: Initial Vulkan support! 2017-08-27 22:15:57 -04:00
Makefile.minimal Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00
Makefile.pandora pandora: Fixed compiler warning about redefining SDL_REVISION. 2017-06-18 23:00:27 +02:00
Makefile.psp PSP: Added missing object for generic TLS to Makefile. 2016-02-13 17:34:14 +01:00
Makefile.wiz Pandora: Updated SDL version in Makefile. 2016-07-19 21:01:30 +02:00
README-SDL.txt More HTTPS changes in the documentation. 2017-02-16 16:52:03 -05:00
README.txt readme: correct webpage URL to use HTTPS. 2017-02-16 13:30:34 -05:00
SDL2.spec.in Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00
SDL2Config.cmake Fixed bug 3651 - CMake build does not install CMake package configuration 2017-08-09 19:03:10 -07:00
TODO.txt Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00
VisualC.html Fixed two typos in documentation. 2016-01-12 22:23:53 +01:00
WhatsNew.txt Added SDL_GameControllerMappingForDeviceIndex() to get the mapping for a controller before it's opened 2018-03-07 13:30:40 -08:00
autogen.sh Don't use pushd/popd in autogen.sh; Ubuntu's /bin/sh doesn't support it. 2016-12-26 22:58:58 -05:00
cmake_uninstall.cmake.in Fixed bug 3867 - Can't find install_manifest.txt when running 'uninstall' target 2017-10-12 08:44:45 -07:00
configure Fixed bug 4154 - Fix three empty variable tests in configure 2018-05-05 10:31:03 -07:00
configure.in Fixed bug 4154 - Fix three empty variable tests in configure 2018-05-05 10:31:03 -07:00
sdl2-config.cmake.in Applied Ubuntu patch bug_822210_fix_sdl2-config.cmake_whitespace.patch 2016-10-07 15:08:37 -07:00
sdl2-config.in Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00
sdl2.m4 Fixed bug 3429 - Update AM_PATH_SDL2() to also check for SDL2.framework 2016-09-29 16:37:08 -07:00
sdl2.pc.in Fixed crash if initialization of EGL failed but was tried again later. 2015-06-21 17:33:46 +02:00

README.txt

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.


                         Simple DirectMedia Layer

                                  (SDL)

                                Version 2.0

---
https://www.libsdl.org/

Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.

More extensive documentation is available in the docs directory, starting
with README.md

Enjoy!
	Sam Lantinga				(slouken@libsdl.org)