Cross-platform, sophisticated frontend for the libretro API. Licensed GPLv3.
Go to file
2020-02-18 02:53:28 +01:00
.github Update FUNDING.yml 2019-10-14 01:33:37 +02:00
.vscode Move menu_widgets to gfx/ and call it gfx_widgets 2020-02-17 01:54:07 +01:00
audio (JACK) Get rid of configuration.h dependency 2020-02-12 17:13:47 +01:00
bootstrap [VITA] Fixing gl1 video driver crashes. 2019-11-12 15:37:37 +01:00
camera/drivers Cleanups 2020-02-04 06:05:00 +01:00
cheevos-new Get rid of menu_texture_item 2020-02-17 22:28:21 +01:00
cores Fix crash on seeking when using HW decoding in some cases. 2020-02-04 21:29:35 +01:00
ctr Cleanups 2020-02-04 06:05:00 +01:00
defines
deps qb: Support building with a system version of glslang. 2020-02-01 16:12:54 -08:00
discord Merge branch 'master' of git://github.com/celerizer/RetroArch into celerizer-test 2020-02-14 21:56:14 +01:00
dist-scripts Update dist-cores.sh 2019-11-19 10:04:45 +01:00
docs Revert "Remove BSV code - was obsolete and no longer working - input recording" 2019-07-08 18:21:46 +02:00
emscripten emscripten: add hack to prevent ERRNO_CODES from being optimized away 2019-08-07 22:07:09 -05:00
frontend Try to make it more portable for BSD 2020-02-16 19:37:59 +01:00
gfx HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
griffin HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
input Try to make it more portable for BSD 2020-02-16 19:37:59 +01:00
intl French translation update 2020-02-15 13:37:33 +07:00
led (led_driver) Take out settings_t dependency 2020-02-14 14:05:35 +01:00
libretro-common Update audio resampler 2020-02-07 07:53:23 +01:00
libretro-db Cleanups 2020-02-04 06:05:00 +01:00
location/drivers Cleanups 2020-02-04 06:05:00 +01:00
managers (Managers) Get rid of settings_t dependencies 2020-02-14 14:24:38 +01:00
media Move #pragma code_page(932) into rarch.rc, as #pragma code_page is ignored for included files. Fixes locale problems for Japanese resources. 2019-05-21 20:09:05 -05:00
memory
menu (Ozone) Add two TODO/FIXMEs 2020-02-17 22:45:13 +01:00
midi Style nits 2020-02-10 13:18:27 +01:00
network (network) Turn some functions into static functions 2020-02-12 20:06:21 +01:00
pkg (MSVC 2005) Add HAVE_OZONE 2020-02-18 02:53:28 +01:00
ps2 (PS2) Cleanups 2020-02-14 17:43:00 +01:00
qb HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
record/drivers (record_ffmpeg) No more settings_t dependency 2020-02-13 21:48:52 +01:00
reference Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
samples/tasks/database Split up VFS file_path code into separate file 2020-01-09 15:44:48 +01:00
shaders Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
shaders-hlsl Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
shaders-hlsl-no-opt/asm/frag Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
shaders-msl Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
shaders-no-opt/asm/frag Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
tasks HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
tests-other Squashed 'deps/SPIRV-Cross/' changes from 9c57364f18..8aa6731925 2019-07-09 18:49:50 +02:00
tools Replace while (1) with for (;;) - avoids MSVC warnings 2020-01-30 16:15:52 +01:00
ui qt: add menu widget scaling new settings 2020-02-14 21:44:35 +01:00
uwp Turn while (true) into for (;;) for easier MSVC backwards compatibility 2020-02-01 04:15:22 +01:00
wifi HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
wii (Wii) Style nits 2020-02-14 17:43:58 +01:00
wiiu Prevent warnings 2020-02-10 20:45:17 +01:00
.editorconfig
.gitignore (iOS/tvOS): IOS/tvOS build fixes: 2019-09-14 12:59:22 -07:00
.gitlab-ci.yml add restart menu option 2019-05-21 04:25:34 +02:00
.project
.travis.yml Added additional CI test for passing sysroot flags via CC and CXX. 2020-01-09 23:14:50 +01:00
10bpc-gl.diff Clean up white space. 2019-02-03 16:00:50 -08:00
accessibility.h (Accessibility) Cleanups 2020-01-12 22:04:31 +01:00
AUTHORS.h update AUTHORS.h with github-contributors script 2019-05-07 21:41:49 -04:00
autosave.h
CHANGES.md Update CHANGES.md 2020-02-17 16:44:33 +01:00
command.h Turn command_set_shader private 2020-02-01 17:17:36 +01:00
config.def.h HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
config.def.keybinds.h Revert "Get rid of send debug info - if we ever bring this back, needs to be" 2020-01-25 15:55:11 +01:00
config.features.h Initial port to dingux platform 2020-01-04 12:20:03 -05:00
configuration.c Get rid of header include 2020-02-16 16:54:58 +01:00
configuration.h menu_thumbnail and menu_thumbnail_path now decoupled from menu 2020-02-16 16:38:17 +01:00
configure qb: Don't create config.log with ./configure --help. 2019-07-28 22:12:26 -07:00
content.h [subsystem] add a function to get the friendly name 2019-04-11 18:51:27 -05:00
CONTRIBUTING.md Update CONTRIBUTING.md 2019-12-05 06:00:02 +01:00
COPYING
core_info.c Cleanup 2020-02-16 20:27:22 +01:00
core_info.h add "required hw api" to core info files, block content loading if core is incompatible with current graphics API/version 2019-07-23 22:44:45 -04:00
core_type.h initial cdrom reading work 2019-06-30 18:33:59 -04:00
core_updater_list.c Start reducing dependency on settings struct 2020-01-02 17:41:52 +01:00
core_updater_list.h Start reducing dependency on settings struct 2020-01-02 17:41:52 +01:00
core.h (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
database_info.c Header cleanups 2020-01-25 17:51:07 +01:00
database_info.h update copyright 2019-02-22 19:13:36 -05:00
defaults.h (Gradle/Android Studio) Update 2019-07-10 12:21:18 +02:00
disk_control_interface.c (libnx) Try to silence warnings 2020-02-10 12:36:11 +01:00
disk_control_interface.h (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
disk_index_file.c (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
disk_index_file.h (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
Doxyfile doxygen: quiet output 2018-09-30 23:37:45 -04:00
driver.h Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
dynamic.h Create HAS_SET_SUBSYSTEMS for rarch_ctl 2019-12-30 07:46:33 +01:00
fetch-submodules.sh Clean up white space. 2019-02-03 16:00:50 -08:00
file_path_special.c Get rid of fill_pathname_slash here 2020-02-18 02:42:41 +01:00
file_path_special.h (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
file_path_str.c (Disk Control Interface) Add support for saving/restoring last used disk in playlists + code overhaul 2020-01-22 17:09:12 +00:00
github-contributors.py update AUTHORS.h with github-contributors script 2019-05-07 21:41:49 -04:00
lakka.h Wi-Fi Access Point in RetroArch Settings 2019-10-05 13:18:15 +02:00
list_special.h dir_list_new_special - no more dependency on settings_t 2020-02-14 12:12:59 +01:00
Makefile qb: Improve the NOUNUSED checks. 2020-01-15 11:05:38 -08:00
Makefile.apple Clean up white space. 2019-02-03 16:00:50 -08:00
Makefile.classic_sega_mini SEGA Mini/SNESC update 2019-09-29 21:41:13 +01:00
Makefile.classic_snesc SEGA Mini/SNESC update 2019-09-29 21:41:13 +01:00
Makefile.common HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.ctr Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.ctr.salamander Update Makefile.ctr.salamander 2020-01-09 15:49:24 +01:00
Makefile.dingux HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.emscripten HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.griffin HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.libnx HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.libogc Clean up white space. 2019-02-03 16:00:50 -08:00
Makefile.msvc HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.openpandora Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.orbis HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.pandora Clean up white space. 2019-02-03 16:00:50 -08:00
Makefile.ps2 Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.ps3 HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.ps3.cobra Get rid of unused code libdbgfont 2019-08-13 11:42:46 +02:00
Makefile.ps3.salamander Split up VFS file_path code into separate file 2020-01-09 15:44:48 +01:00
Makefile.psl1ght Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.psp1 Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.psp1.salamander Split up VFS file_path code into separate file 2020-01-09 15:44:48 +01:00
Makefile.switch Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.vita HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
Makefile.vita.salamander Split up VFS file_path code into separate file 2020-01-09 15:44:48 +01:00
Makefile.wii.salamander Split up VFS file_path code into separate file 2020-01-09 15:44:48 +01:00
Makefile.wiiu Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
Makefile.win Add back HAVE_CONFIGFILE ifdef - will strip out remaps and overrides 2020-02-02 21:27:38 +01:00
manual_content_scan.c dir_list_new_special - no more dependency on settings_t 2020-02-14 12:12:59 +01:00
manual_content_scan.h dir_list_new_special - no more dependency on settings_t 2020-02-14 12:12:59 +01:00
msg_hash.c More build fixes. 2019-12-04 20:11:02 -08:00
msg_hash.h Merge pull request from guoyunhe/translation-update-script 2020-02-15 02:39:31 +01:00
no-xib.diff Clean up white space. 2019-02-03 16:00:50 -08:00
paths.h Cleanups 2020-02-01 03:27:58 +01:00
performance_counters.c implement video_shader_delay setting (in ms), which delays auto-shaders 2019-08-27 16:01:48 +02:00
performance_counters.h implement video_shader_delay setting (in ms), which delays auto-shaders 2019-08-27 16:01:48 +02:00
playlist.c Cleanups 2020-02-03 07:44:00 +01:00
playlist.h menu_thumbnail and menu_thumbnail_path now decoupled from menu 2020-02-16 16:38:17 +01:00
README-exynos.md
README-mali_fbdev_r4p0.md Re-enable RXML and purge libxml 2019-03-17 03:04:35 +00:00
README-OMAP.md
README.md Re-enable RXML and purge libxml 2019-03-17 03:04:35 +00:00
retroarch-android-debug.diff
retroarch-mingw-build.sh Clean up white space. 2019-02-03 16:00:50 -08:00
retroarch.c Fix memory leak 2020-02-18 02:02:22 +01:00
retroarch.cfg (Playlists) Make sure history list can be set to 1 as a bare minimum - 2020-01-09 16:49:52 +01:00
retroarch.desktop
retroarch.h HAVE_MENU_WIDGETS now decoupled from HAVE_MENU 2020-02-17 21:28:42 +01:00
runtime_file.c Improve ifdef - should be compiled in only if HAVE_OZONE is defined 2020-02-14 14:31:02 +01:00
runtime_file.h Move enums to related header 2020-02-17 03:06:07 +01:00
setting_list.h (Menu settings) Turn function static and some style nits 2019-08-20 03:44:17 +02:00
switch_performance_profiles.h lakka-switch: adding extra overclocks 2019-05-11 21:05:57 -04:00
translation_defines.h Remove unfinished translation files 2019-09-08 20:14:23 -07:00
travis_metal_deploy.sh Wait longer for the notarization server 2019-11-21 11:12:54 +07:00
travis-deploy-key.enc travis: deploy OSX Metal build 2018-09-02 21:57:06 -04:00
verbosity.c Remove retro_main_log_file function 2020-02-01 23:56:51 +01:00
verbosity.h Remove retro_main_log_file function 2020-02-01 23:56:51 +01:00
version_git.c Remove trailing blank lines. 2019-01-17 19:39:38 -08:00
version_git.h Remove trailing blank lines. 2019-01-17 19:39:38 -08:00
version.all Update version.all 2020-01-15 17:05:43 +01:00
version.dtd Update version.dtd 2020-01-15 17:06:00 +01:00
version.h
wiiu-devel.properties.template

Build Status Coverity Scan Build Status

RetroArch

RetroArch is the reference frontend for the libretro API. Popular examples of implementations for this API includes video game system emulators and game engines as well as more generalized 3D programs. These programs are instantiated as dynamic libraries. We refer to these as "libretro cores".

XMB menu driver

rgui menu driver

glui menu driver

libretro

libretro is an API that exposes generic audio/video/input callbacks. A frontend for libretro (such as RetroArch) handles video output, audio output, input and application lifecycle. A libretro core written in portable C or C++ can run seamlessly on many platforms with very little to no porting effort.

While RetroArch is the reference frontend for libretro, several other projects have used the libretro interface to include support for emulators and/or game engines. libretro is completely open and free for anyone to use.

libretro API header

Binaries

Latest binaries are currently hosted on the buildbot.

Support

To reach developers, either make an issue here on GitHub, make a thread on the forum, chat on discord, or visit our IRC channel: #retroarch @ irc.freenode.org.

Documentation

See our Documentation Center. On Unix, man-pages are provided. More developer-centric stuff is found here.

Philosophy

RetroArch attempts to be small and lean while still having all the useful core features expected from an emulator. It is designed to be very portable and features a gamepad-centric and touchscreen UI. It also has a full-featured command-line interface.

In some areas, RetroArch goes beyond and emphasizes on not-so-common technical features such as multi-pass shader support, real-time rewind (Braid-style), video recording (using FFmpeg), run-ahead input latency removal, etc.

RetroArch also emphasizes being easy to integrate into various launcher frontends.

Platforms

RetroArch has been ported to the following platforms:

  • DOS
  • Windows
  • Linux
  • Emscripten (WebAssembly and JavaScript)
  • FreeBSD
  • NetBSD
  • OpenBSD
  • Haiku
  • Solaris
  • macOS (PPC, x86-32 and x86-64)
  • PlayStation 3
  • PlayStation Portable
  • PlayStation Vita
  • Original Microsoft Xbox
  • Microsoft Xbox 360 (Libxenon/XeXDK)
  • Nintendo GameCube
  • Nintendo Wii
  • Nintendo Wii U
  • Nintendo 3DS
  • Nintendo Switch
  • Nintendo NES/SNES Classic Edition
  • Raspberry Pi
  • Android
  • iOS
  • Blackberry

Dependencies (PC)

There are no true hard dependencies per se.

On Windows, RetroArch can run with only Win32 as dependency.

On Linux, there are no true dependencies. For optimal usage, the following dependencies come as recommended:

  • GL headers / Vulkan headers
  • X11 headers and libs, or EGL/KMS/GBM

OSX port of RetroArch requires latest versions of XCode to build.

RetroArch can utilize these libraries if enabled:

  • nvidia-cg-toolkit
  • libfreetype2 (TTF font rendering on screen)

RetroArch needs at least one of these audio driver libraries:

  • ALSA
  • OSS
  • RoarAudio
  • RSound
  • OpenAL
  • JACK
  • SDL
  • PulseAudio
  • XAudio2 (Win32, Xbox 360)
  • DirectSound (Win32, Xbox 1)
  • CoreAudio (OSX, iOS)

To run properly, RetroArch requires a libretro implementation present; however, as it's typically loaded dynamically, it's not required at build time.

Dependencies (Console ports, mobile)

Console ports have their own dependencies, but generally do not require anything other than what the respective SDKs provide.

Configuring

The default configuration is defined in config.def.h. It is not recommended to change this unless you know what you're doing. These can later be tweaked by using a config file. A sample configuration file is installed to /etc/retroarch.cfg. This is the system-wide config file.

RetroArch will on startup create a config file in $XDG\_CONFIG\_HOME/retroarch/retroarch.cfg if it does not exist. Users only need to configure a certain option if the desired value deviates from the value defined in config.def.h.

To configure joypads, use the built-in menu or the retroarch-joyconfig command-line tool.

Compiling and installing

Instructions for compiling and installing RetroArch can be found in the Libretro/RetroArch Documentation Center.

CRT 15Khz Resolution Switching

CRT SwitchRes will turn on, on the fly. However, you will need to restart RetroArch to disable it. With CRT SwitchRes enable RetroArch will start in 2560 x 480 @ 60.

If you are running Windows, before enabling the CRT SwitchRes options please make sure you have installed CRTEmudriver and installed some modelines. The minimum modelines for all games to switch correctly are:

  • 2560 x 192 @ 60.000000
  • 2560 x 200 @ 60.000000
  • 2560 x 240 @ 60.000000
  • 2560 x 224 @ 60.000000
  • 2560 x 237 @ 60.000000
  • 2560 x 256 @ 50.000000
  • 2560 x 254 @ 55.000000
  • 2560 x 448 @ 60.000000
  • 2560 x 480 @ 60.000000

Install these modelines replacing 2560 with your desired super resolution. The above resolutions are NTSC only so if you would be playing any PAL content please add PAL modelines:

  • 2560 x 192 @ 50.000000
  • 2560 x 200 @ 50.000000
  • 2560 x 240 @ 50.000000
  • 2560 x 224 @ 50.000000
  • 2560 x 288 @ 50.000000
  • 2560 x 237 @ 50.000000
  • 2560 x 254 @ 55.000000
  • 2560 x 448 @ 50.000000
  • 2560 x 480 @ 50.000000

Some games will require higher PAL resolutions which should also be installed:

  • 2560 x 512 @ 50.000000
  • 2560 x 576 @ 50.000000

Ideally install all these modelines and everything will work great.

Super Resolutions

The default super resolution is 2560. It is displayed just under the CRT switch option, which can be found in video settings. This can be changed within the retroarch.cfg. The only compatible resolutions are 1920, 2560 and 3840. Any other resolutions will be ignored and native switching will be activated.

Native Resolutions

If native resolutions are activated you will need a whole new set of modelines:

  • 256 x 240 @ 50.006977 SNESpal

  • 256 x 448 @ 50.006977 SNESpal

  • 512 x 224 @ 50.006977 SNESpal

  • 512 x 240 @ 50.006977 SNESpal

  • 512 x 448 @ 50.006977 SNESpal

  • 256 x 240 @ 60.098812 SNESntsc

  • 256 x 448 @ 60.098812 SNESntsc

  • 512 x 240 @ 60.098812 SNESntsc

  • 512 x 224 @ 60.098812 SNESntsc

  • 512 x 448 @ 60.098812 SNESntsc

  • 256 x 192 @ 59.922745 MDntsc

  • 256 x 224 @ 59.922745 MDntsc

  • 320 x 224 @ 59.922745 MDntsc

  • 320 x 240 @ 59.922745 MDntsc

  • 320 x 448 @ 59.922745 MDntsc

  • 320 x 480 @ 59.922745 MDntsc

  • 256 x 192 @ 49.701458 MDpal

  • 256 x 224 @ 49.701458 MDpal

  • 320 x 224 @ 49.701458 MDpal

  • 320 x 240 @ 49.701458 MDpal

  • 320 x 288 @ 49.701458 MDpal

  • 320 x 448 @ 49.701458 MDpal

  • 320 x 480 @ 49.701458 MDpal

  • 320 x 576 @ 49.701458 MDpal

  • 256 x 288 @ 49.701458 MSYSpal

  • 256 x 240 @ 60.098812 NESntsc

  • 256 x 240 @ 50.006977 NESpal

  • 640 x 237 @ 60.130001 N64ntsc

  • 640 x 240 @ 60.130001 N64ntsc

  • 640 x 480 @ 60.130001 N64ntsc

  • 640 x 288 @ 50.000000 N64pal

  • 640 x 480 @ 50.000000 N64pal

  • 640 x 576 @ 50.000000 N64pal

  • 256 x 252 @ 49.759998 PSXpal

  • 320 x 252 @ 49.759998 PSXpal

  • 384 x 252 @ 49.759998 PSXpal

  • 640 x 252 @ 49.759998 PSXpal

  • 640 x 540 @ 49.759998 PSXpal

  • 384 x 240 @ 59.941002 PSXntsc

  • 256 x 480 @ 59.941002 PSXntsc

  • 352 x 240 @ 59.820000 Saturn/SGFX_NTSCp

  • 704 x 240 @ 59.820000 SaturnNTSCp

  • 352 x 480 @ 59.820000 SaturnNTSCi

  • 704 x 480 @ 59.820000 SaturnNTSCi

  • 352 x 288 @ 49.701458 SaturnPALp

  • 704 x 288 @ 49.701458 SaturnPALp

  • 352 x 576 @ 49.701458 SaturnPALi

  • 704 x 576 @ 49.701458 SaturnPALi

  • 240 x 160 @ 59.730000 GBA

  • 320 x 200 @ 60.000000 Doom

// Arcade

  • 400 x 254 @ 54.706841 MK
  • 384 x 224 @ 59.637405 CPS1

These modelines are more accurate giving exact hz. However, some games may have unwanted results. This is due to mid-scanline resolution changes on the original hardware. For the best results super resolutions are the way to go.

CRT resolution switching & MAME

Some arcade resolutions can be very different from consumer CRTs. There is resolution detection to ensure MAME games will be displayed in the closest available resolution but drawn at their native resolution within this resolution. Meaning that the MAME game will look just like the original hardware.

MAME ROMs that run in a vertical aspect like DoDonPachi need to be rotated within MAME before resolution switching and aspect correction will work. Do this before enabling CRT SwitchRes so that RetroArch will run in your desktop resolution. Once you have rotated any games that may need it turn CRT SwitchRes on.