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libretro.h
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libretro.h
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/* Copyright (C) 2010-2014 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this libretro API header (libretro.h).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef LIBRETRO_H__
#define LIBRETRO_H__
#include <stdint.h>
#include <stddef.h>
#include <limits.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef __cplusplus
#if defined(_MSC_VER) && !defined(SN_TARGET_PS3)
/* Hack applied for MSVC when compiling in C89 mode as it isn't C99 compliant. */
#define bool unsigned char
#define true 1
#define false 0
#else
#include <stdbool.h>
#endif
#endif
// Used for checking API/ABI mismatches that can break libretro implementations.
// It is not incremented for compatible changes to the API.
#define RETRO_API_VERSION 1
//
// Libretros fundamental device abstractions.
/////////
//
// Libretros input system consists of some standardized device types such as a joypad (with/without analog),
// mouse, keyboard, lightgun and a pointer. The functionality of these devices are fixed, and individual cores map
// their own concept of a controller to libretros abstractions.
// This makes it possible for frontends to map the abstract types to a real input device,
// and not having to worry about binding input correctly to arbitrary controller layouts.
#define RETRO_DEVICE_TYPE_SHIFT 8
#define RETRO_DEVICE_MASK ((1 << RETRO_DEVICE_TYPE_SHIFT) - 1)
#define RETRO_DEVICE_SUBCLASS(base, id) (((id + 1) << RETRO_DEVICE_TYPE_SHIFT) | base)
// Input disabled.
#define RETRO_DEVICE_NONE 0
// The JOYPAD is called RetroPad. It is essentially a Super Nintendo controller,
// but with additional L2/R2/L3/R3 buttons, similar to a PS1 DualShock.
#define RETRO_DEVICE_JOYPAD 1
// The mouse is a simple mouse, similar to Super Nintendo's mouse.
// X and Y coordinates are reported relatively to last poll (poll callback).
// It is up to the libretro implementation to keep track of where the mouse pointer is supposed to be on the screen.
// The frontend must make sure not to interfere with its own hardware mouse pointer.
#define RETRO_DEVICE_MOUSE 2
// KEYBOARD device lets one poll for raw key pressed.
// It is poll based, so input callback will return with the current pressed state.
// For event/text based keyboard input, see RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK.
#define RETRO_DEVICE_KEYBOARD 3
// Lightgun X/Y coordinates are reported relatively to last poll, similar to mouse.
#define RETRO_DEVICE_LIGHTGUN 4
// The ANALOG device is an extension to JOYPAD (RetroPad).
// Similar to DualShock it adds two analog sticks.
// This is treated as a separate device type as it returns values in the full analog range
// of [-0x8000, 0x7fff]. Positive X axis is right. Positive Y axis is down.
// Only use ANALOG type when polling for analog values of the axes.
#define RETRO_DEVICE_ANALOG 5
// Abstracts the concept of a pointing mechanism, e.g. touch.
// This allows libretro to query in absolute coordinates where on the screen a mouse (or something similar) is being placed.
// For a touch centric device, coordinates reported are the coordinates of the press.
//
// Coordinates in X and Y are reported as:
// [-0x7fff, 0x7fff]: -0x7fff corresponds to the far left/top of the screen,
// and 0x7fff corresponds to the far right/bottom of the screen.
// The "screen" is here defined as area that is passed to the frontend and later displayed on the monitor.
// The frontend is free to scale/resize this screen as it sees fit, however,
// (X, Y) = (-0x7fff, -0x7fff) will correspond to the top-left pixel of the game image, etc.
//
// To check if the pointer coordinates are valid (e.g. a touch display actually being touched),
// PRESSED returns 1 or 0.
// If using a mouse on a desktop, PRESSED will usually correspond to the left mouse button, but this is a frontend decision.
// PRESSED will only return 1 if the pointer is inside the game screen.
//
// For multi-touch, the index variable can be used to successively query more presses.
// If index = 0 returns true for _PRESSED, coordinates can be extracted
// with _X, _Y for index = 0. One can then query _PRESSED, _X, _Y with index = 1, and so on.
// Eventually _PRESSED will return false for an index. No further presses are registered at this point.
#define RETRO_DEVICE_POINTER 6
// Buttons for the RetroPad (JOYPAD).
// The placement of these is equivalent to placements on the Super Nintendo controller.
// L2/R2/L3/R3 buttons correspond to the PS1 DualShock.
#define RETRO_DEVICE_ID_JOYPAD_B 0
#define RETRO_DEVICE_ID_JOYPAD_Y 1
#define RETRO_DEVICE_ID_JOYPAD_SELECT 2
#define RETRO_DEVICE_ID_JOYPAD_START 3
#define RETRO_DEVICE_ID_JOYPAD_UP 4
#define RETRO_DEVICE_ID_JOYPAD_DOWN 5
#define RETRO_DEVICE_ID_JOYPAD_LEFT 6
#define RETRO_DEVICE_ID_JOYPAD_RIGHT 7
#define RETRO_DEVICE_ID_JOYPAD_A 8
#define RETRO_DEVICE_ID_JOYPAD_X 9
#define RETRO_DEVICE_ID_JOYPAD_L 10
#define RETRO_DEVICE_ID_JOYPAD_R 11
#define RETRO_DEVICE_ID_JOYPAD_L2 12
#define RETRO_DEVICE_ID_JOYPAD_R2 13
#define RETRO_DEVICE_ID_JOYPAD_L3 14
#define RETRO_DEVICE_ID_JOYPAD_R3 15
// Index / Id values for ANALOG device.
#define RETRO_DEVICE_INDEX_ANALOG_LEFT 0
#define RETRO_DEVICE_INDEX_ANALOG_RIGHT 1
#define RETRO_DEVICE_ID_ANALOG_X 0
#define RETRO_DEVICE_ID_ANALOG_Y 1
// Id values for MOUSE.
#define RETRO_DEVICE_ID_MOUSE_X 0
#define RETRO_DEVICE_ID_MOUSE_Y 1
#define RETRO_DEVICE_ID_MOUSE_LEFT 2
#define RETRO_DEVICE_ID_MOUSE_RIGHT 3
// Id values for LIGHTGUN types.
#define RETRO_DEVICE_ID_LIGHTGUN_X 0
#define RETRO_DEVICE_ID_LIGHTGUN_Y 1
#define RETRO_DEVICE_ID_LIGHTGUN_TRIGGER 2
#define RETRO_DEVICE_ID_LIGHTGUN_CURSOR 3
#define RETRO_DEVICE_ID_LIGHTGUN_TURBO 4
#define RETRO_DEVICE_ID_LIGHTGUN_PAUSE 5
#define RETRO_DEVICE_ID_LIGHTGUN_START 6
// Id values for POINTER.
#define RETRO_DEVICE_ID_POINTER_X 0
#define RETRO_DEVICE_ID_POINTER_Y 1
#define RETRO_DEVICE_ID_POINTER_PRESSED 2
// Returned from retro_get_region().
#define RETRO_REGION_NTSC 0
#define RETRO_REGION_PAL 1
// Passed to retro_get_memory_data/size().
// If the memory type doesn't apply to the implementation NULL/0 can be returned.
#define RETRO_MEMORY_MASK 0xff
// Regular save ram. This ram is usually found on a game cartridge, backed up by a battery.
// If save game data is too complex for a single memory buffer,
// the SAVE_DIRECTORY (preferably) or SYSTEM_DIRECTORY environment callback can be used.
#define RETRO_MEMORY_SAVE_RAM 0
// Some games have a built-in clock to keep track of time.
// This memory is usually just a couple of bytes to keep track of time.
#define RETRO_MEMORY_RTC 1
// System ram lets a frontend peek into a game systems main RAM.
#define RETRO_MEMORY_SYSTEM_RAM 2
// Video ram lets a frontend peek into a game systems video RAM (VRAM).
#define RETRO_MEMORY_VIDEO_RAM 3
// Keysyms used for ID in input state callback when polling RETRO_KEYBOARD.
enum retro_key
{
RETROK_UNKNOWN = 0,
RETROK_FIRST = 0,
RETROK_BACKSPACE = 8,
RETROK_TAB = 9,
RETROK_CLEAR = 12,
RETROK_RETURN = 13,
RETROK_PAUSE = 19,
RETROK_ESCAPE = 27,
RETROK_SPACE = 32,
RETROK_EXCLAIM = 33,
RETROK_QUOTEDBL = 34,
RETROK_HASH = 35,
RETROK_DOLLAR = 36,
RETROK_AMPERSAND = 38,
RETROK_QUOTE = 39,
RETROK_LEFTPAREN = 40,
RETROK_RIGHTPAREN = 41,
RETROK_ASTERISK = 42,
RETROK_PLUS = 43,
RETROK_COMMA = 44,
RETROK_MINUS = 45,
RETROK_PERIOD = 46,
RETROK_SLASH = 47,
RETROK_0 = 48,
RETROK_1 = 49,
RETROK_2 = 50,
RETROK_3 = 51,
RETROK_4 = 52,
RETROK_5 = 53,
RETROK_6 = 54,
RETROK_7 = 55,
RETROK_8 = 56,
RETROK_9 = 57,
RETROK_COLON = 58,
RETROK_SEMICOLON = 59,
RETROK_LESS = 60,
RETROK_EQUALS = 61,
RETROK_GREATER = 62,
RETROK_QUESTION = 63,
RETROK_AT = 64,
RETROK_LEFTBRACKET = 91,
RETROK_BACKSLASH = 92,
RETROK_RIGHTBRACKET = 93,
RETROK_CARET = 94,
RETROK_UNDERSCORE = 95,
RETROK_BACKQUOTE = 96,
RETROK_a = 97,
RETROK_b = 98,
RETROK_c = 99,
RETROK_d = 100,
RETROK_e = 101,
RETROK_f = 102,
RETROK_g = 103,
RETROK_h = 104,
RETROK_i = 105,
RETROK_j = 106,
RETROK_k = 107,
RETROK_l = 108,
RETROK_m = 109,
RETROK_n = 110,
RETROK_o = 111,
RETROK_p = 112,
RETROK_q = 113,
RETROK_r = 114,
RETROK_s = 115,
RETROK_t = 116,
RETROK_u = 117,
RETROK_v = 118,
RETROK_w = 119,
RETROK_x = 120,
RETROK_y = 121,
RETROK_z = 122,
RETROK_DELETE = 127,
RETROK_KP0 = 256,
RETROK_KP1 = 257,
RETROK_KP2 = 258,
RETROK_KP3 = 259,
RETROK_KP4 = 260,
RETROK_KP5 = 261,
RETROK_KP6 = 262,
RETROK_KP7 = 263,
RETROK_KP8 = 264,
RETROK_KP9 = 265,
RETROK_KP_PERIOD = 266,
RETROK_KP_DIVIDE = 267,
RETROK_KP_MULTIPLY = 268,
RETROK_KP_MINUS = 269,
RETROK_KP_PLUS = 270,
RETROK_KP_ENTER = 271,
RETROK_KP_EQUALS = 272,
RETROK_UP = 273,
RETROK_DOWN = 274,
RETROK_RIGHT = 275,
RETROK_LEFT = 276,
RETROK_INSERT = 277,
RETROK_HOME = 278,
RETROK_END = 279,
RETROK_PAGEUP = 280,
RETROK_PAGEDOWN = 281,
RETROK_F1 = 282,
RETROK_F2 = 283,
RETROK_F3 = 284,
RETROK_F4 = 285,
RETROK_F5 = 286,
RETROK_F6 = 287,
RETROK_F7 = 288,
RETROK_F8 = 289,
RETROK_F9 = 290,
RETROK_F10 = 291,
RETROK_F11 = 292,
RETROK_F12 = 293,
RETROK_F13 = 294,
RETROK_F14 = 295,
RETROK_F15 = 296,
RETROK_NUMLOCK = 300,
RETROK_CAPSLOCK = 301,
RETROK_SCROLLOCK = 302,
RETROK_RSHIFT = 303,
RETROK_LSHIFT = 304,
RETROK_RCTRL = 305,
RETROK_LCTRL = 306,
RETROK_RALT = 307,
RETROK_LALT = 308,
RETROK_RMETA = 309,
RETROK_LMETA = 310,
RETROK_LSUPER = 311,
RETROK_RSUPER = 312,
RETROK_MODE = 313,
RETROK_COMPOSE = 314,
RETROK_HELP = 315,
RETROK_PRINT = 316,
RETROK_SYSREQ = 317,
RETROK_BREAK = 318,
RETROK_MENU = 319,
RETROK_POWER = 320,
RETROK_EURO = 321,
RETROK_UNDO = 322,
RETROK_LAST,
RETROK_DUMMY = INT_MAX // Ensure sizeof(enum) == sizeof(int)
};
enum retro_mod
{
RETROKMOD_NONE = 0x0000,
RETROKMOD_SHIFT = 0x01,
RETROKMOD_CTRL = 0x02,
RETROKMOD_ALT = 0x04,
RETROKMOD_META = 0x08,
RETROKMOD_NUMLOCK = 0x10,
RETROKMOD_CAPSLOCK = 0x20,
RETROKMOD_SCROLLOCK = 0x40,
RETROKMOD_DUMMY = INT_MAX // Ensure sizeof(enum) == sizeof(int)
};
// If set, this call is not part of the public libretro API yet. It can change or be removed at any time.
#define RETRO_ENVIRONMENT_EXPERIMENTAL 0x10000
// Environment callback to be used internally in frontend.
#define RETRO_ENVIRONMENT_PRIVATE 0x20000
// Environment commands.
#define RETRO_ENVIRONMENT_SET_ROTATION 1 // const unsigned * --
// Sets screen rotation of graphics.
// Is only implemented if rotation can be accelerated by hardware.
// Valid values are 0, 1, 2, 3, which rotates screen by 0, 90, 180, 270 degrees
// counter-clockwise respectively.
//
#define RETRO_ENVIRONMENT_GET_OVERSCAN 2 // bool * --
// Boolean value whether or not the implementation should use overscan, or crop away overscan.
//
#define RETRO_ENVIRONMENT_GET_CAN_DUPE 3 // bool * --
// Boolean value whether or not frontend supports frame duping,
// passing NULL to video frame callback.
//
// Environ 4, 5 are no longer supported (GET_VARIABLE / SET_VARIABLES), and reserved to avoid possible ABI clash.
#define RETRO_ENVIRONMENT_SET_MESSAGE 6 // const struct retro_message * --
// Sets a message to be displayed in implementation-specific manner for a certain amount of 'frames'.
// Should not be used for trivial messages, which should simply be logged via RETRO_ENVIRONMENT_GET_LOG_INTERFACE (or as a fallback, stderr).
#define RETRO_ENVIRONMENT_SHUTDOWN 7 // N/A (NULL) --
// Requests the frontend to shutdown.
// Should only be used if game has a specific
// way to shutdown the game from a menu item or similar.
//
#define RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL 8
// const unsigned * --
// Gives a hint to the frontend how demanding this implementation
// is on a system. E.g. reporting a level of 2 means
// this implementation should run decently on all frontends
// of level 2 and up.
//
// It can be used by the frontend to potentially warn
// about too demanding implementations.
//
// The levels are "floating", but roughly defined as:
// 0: Low-powered embedded devices such as Raspberry Pi
// 1: 6th generation consoles, such as Wii/Xbox 1, and phones, tablets, etc.
// 2: 7th generation consoles, such as PS3/360, with sub-par CPUs.
// 3: Modern desktop/laptops with reasonably powerful CPUs.
// 4: High-end desktops with very powerful CPUs.
//
// This function can be called on a per-game basis,
// as certain games an implementation can play might be
// particularily demanding.
// If called, it should be called in retro_load_game().
//
#define RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY 9
// const char ** --
// Returns the "system" directory of the frontend.
// This directory can be used to store system specific ROMs such as BIOSes, configuration data, etc.
// The returned value can be NULL.
// If so, no such directory is defined,
// and it's up to the implementation to find a suitable directory.
//
// NOTE: Some cores used this folder also for "save" data such as memory cards, etc, for lack of a better place to put it.
// This is now discouraged, and if possible, cores should try to use the new GET_SAVE_DIRECTORY.
//
#define RETRO_ENVIRONMENT_SET_PIXEL_FORMAT 10
// const enum retro_pixel_format * --
// Sets the internal pixel format used by the implementation.
// The default pixel format is RETRO_PIXEL_FORMAT_0RGB1555.
// This pixel format however, is deprecated (see enum retro_pixel_format).
// If the call returns false, the frontend does not support this pixel format.
// This function should be called inside retro_load_game() or retro_get_system_av_info().
//
#define RETRO_ENVIRONMENT_SET_INPUT_DESCRIPTORS 11
// const struct retro_input_descriptor * --
// Sets an array of retro_input_descriptors.
// It is up to the frontend to present this in a usable way.
// The array is terminated by retro_input_descriptor::description being set to NULL.
// This function can be called at any time, but it is recommended to call it as early as possible.
#define RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK 12
// const struct retro_keyboard_callback * --
// Sets a callback function used to notify core about keyboard events.
//
#define RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE 13
// const struct retro_disk_control_callback * --
// Sets an interface which frontend can use to eject and insert disk images.
// This is used for games which consist of multiple images and must be manually
// swapped out by the user (e.g. PSX).
#define RETRO_ENVIRONMENT_SET_HW_RENDER 14
// struct retro_hw_render_callback * --
// Sets an interface to let a libretro core render with hardware acceleration.
// Should be called in retro_load_game().
// If successful, libretro cores will be able to render to a frontend-provided framebuffer.
// The size of this framebuffer will be at least as large as max_width/max_height provided in get_av_info().
// If HW rendering is used, pass only RETRO_HW_FRAME_BUFFER_VALID or NULL to retro_video_refresh_t.
#define RETRO_ENVIRONMENT_GET_VARIABLE 15
// struct retro_variable * --
// Interface to acquire user-defined information from environment
// that cannot feasibly be supported in a multi-system way.
// 'key' should be set to a key which has already been set by SET_VARIABLES.
// 'data' will be set to a value or NULL.
//
#define RETRO_ENVIRONMENT_SET_VARIABLES 16
// const struct retro_variable * --
// Allows an implementation to signal the environment
// which variables it might want to check for later using GET_VARIABLE.
// This allows the frontend to present these variables to a user dynamically.
// This should be called as early as possible (ideally in retro_set_environment).
//
// 'data' points to an array of retro_variable structs terminated by a { NULL, NULL } element.
// retro_variable::key should be namespaced to not collide with other implementations' keys. E.g. A core called 'foo' should use keys named as 'foo_option'.
// retro_variable::value should contain a human readable description of the key as well as a '|' delimited list of expected values.
// The number of possible options should be very limited, i.e. it should be feasible to cycle through options without a keyboard.
// First entry should be treated as a default.
//
// Example entry:
// { "foo_option", "Speed hack coprocessor X; false|true" }
//
// Text before first ';' is description. This ';' must be followed by a space, and followed by a list of possible values split up with '|'.
// Only strings are operated on. The possible values will generally be displayed and stored as-is by the frontend.
//
#define RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE 17
// bool * --
// Result is set to true if some variables are updated by
// frontend since last call to RETRO_ENVIRONMENT_GET_VARIABLE.
// Variables should be queried with GET_VARIABLE.
//
#define RETRO_ENVIRONMENT_SET_SUPPORT_NO_GAME 18
// const bool * --
// If true, the libretro implementation supports calls to retro_load_game() with NULL as argument.
// Used by cores which can run without particular game data.
// This should be called within retro_set_environment() only.
//
#define RETRO_ENVIRONMENT_GET_LIBRETRO_PATH 19
// const char ** --
// Retrieves the absolute path from where this libretro implementation was loaded.
// NULL is returned if the libretro was loaded statically (i.e. linked statically to frontend), or if the path cannot be determined.
// Mostly useful in cooperation with SET_SUPPORT_NO_GAME as assets can be loaded without ugly hacks.
//
//
// Environment 20 was an obsolete version of SET_AUDIO_CALLBACK. It was not used by any known core at the time,
// and was removed from the API.
#define RETRO_ENVIRONMENT_SET_AUDIO_CALLBACK 22
// const struct retro_audio_callback * --
// Sets an interface which is used to notify a libretro core about audio being available for writing.
// The callback can be called from any thread, so a core using this must have a thread safe audio implementation.
// It is intended for games where audio and video are completely asynchronous and audio can be generated on the fly.
// This interface is not recommended for use with emulators which have highly synchronous audio.
//
// The callback only notifies about writability; the libretro core still has to call the normal audio callbacks
// to write audio. The audio callbacks must be called from within the notification callback.
// The amount of audio data to write is up to the implementation.
// Generally, the audio callback will be called continously in a loop.
//
// Due to thread safety guarantees and lack of sync between audio and video, a frontend
// can selectively disallow this interface based on internal configuration. A core using
// this interface must also implement the "normal" audio interface.
//
// A libretro core using SET_AUDIO_CALLBACK should also make use of SET_FRAME_TIME_CALLBACK.
#define RETRO_ENVIRONMENT_SET_FRAME_TIME_CALLBACK 21
// const struct retro_frame_time_callback * --
// Lets the core know how much time has passed since last invocation of retro_run().
// The frontend can tamper with the timing to fake fast-forward, slow-motion, frame stepping, etc.
// In this case the delta time will use the reference value in frame_time_callback..
//
#define RETRO_ENVIRONMENT_GET_RUMBLE_INTERFACE 23
// struct retro_rumble_interface * --
// Gets an interface which is used by a libretro core to set state of rumble motors in controllers.
// A strong and weak motor is supported, and they can be controlled indepedently.
//
#define RETRO_ENVIRONMENT_GET_INPUT_DEVICE_CAPABILITIES 24
// uint64_t * --
// Gets a bitmask telling which device type are expected to be handled properly in a call to retro_input_state_t.
// Devices which are not handled or recognized always return 0 in retro_input_state_t.
// Example bitmask: caps = (1 << RETRO_DEVICE_JOYPAD) | (1 << RETRO_DEVICE_ANALOG).
// Should only be called in retro_run().
//
#define RETRO_ENVIRONMENT_GET_SENSOR_INTERFACE (25 | RETRO_ENVIRONMENT_EXPERIMENTAL)
// struct retro_sensor_interface * --
// Gets access to the sensor interface.
// The purpose of this interface is to allow
// setting state related to sensors such as polling rate, enabling/disable it entirely, etc.
// Reading sensor state is done via the normal input_state_callback API.
//
#define RETRO_ENVIRONMENT_GET_CAMERA_INTERFACE (26 | RETRO_ENVIRONMENT_EXPERIMENTAL)
// struct retro_camera_callback * --
// Gets an interface to a video camera driver.
// A libretro core can use this interface to get access to a video camera.
// New video frames are delivered in a callback in same thread as retro_run().
//
// GET_CAMERA_INTERFACE should be called in retro_load_game().
//
// Depending on the camera implementation used, camera frames will be delivered as a raw framebuffer,
// or as an OpenGL texture directly.
//
// The core has to tell the frontend here which types of buffers can be handled properly.
// An OpenGL texture can only be handled when using a libretro GL core (SET_HW_RENDER).
// It is recommended to use a libretro GL core when using camera interface.
//
// The camera is not started automatically. The retrieved start/stop functions must be used to explicitly
// start and stop the camera driver.
//
#define RETRO_ENVIRONMENT_GET_LOG_INTERFACE 27
// struct retro_log_callback * --
// Gets an interface for logging. This is useful for logging in a cross-platform way
// as certain platforms cannot use use stderr for logging. It also allows the frontend to
// show logging information in a more suitable way.
// If this interface is not used, libretro cores should log to stderr as desired.
#define RETRO_ENVIRONMENT_GET_PERF_INTERFACE 28
// struct retro_perf_callback * --
// Gets an interface for performance counters. This is useful for performance logging in a
// cross-platform way and for detecting architecture-specific features, such as SIMD support.
#define RETRO_ENVIRONMENT_GET_LOCATION_INTERFACE 29
// struct retro_location_callback * --
// Gets access to the location interface.
// The purpose of this interface is to be able to retrieve location-based information from the host device,
// such as current latitude / longitude.
//
#define RETRO_ENVIRONMENT_GET_CONTENT_DIRECTORY 30
// const char ** --
// Returns the "content" directory of the frontend.
// This directory can be used to store specific assets that the core relies upon, such as art assets,
// input data, etc etc.
// The returned value can be NULL.
// If so, no such directory is defined,
// and it's up to the implementation to find a suitable directory.
//
#define RETRO_ENVIRONMENT_GET_SAVE_DIRECTORY 31
// const char ** --
// Returns the "save" directory of the frontend.
// This directory can be used to store SRAM, memory cards, high scores, etc, if the libretro core
// cannot use the regular memory interface (retro_get_memory_data()).
//
// NOTE: libretro cores used to check GET_SYSTEM_DIRECTORY for similar things before.
// They should still check GET_SYSTEM_DIRECTORY if they want to be backwards compatible.
// The path here can be NULL. It should only be non-NULL if the frontend user has set a specific save path.
//
#define RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO 32
// const struct retro_system_av_info * --
// Sets a new av_info structure. This can only be called from within retro_run().
// This should *only* be used if the core is completely altering the internal resolutions, aspect ratios, timings, sampling rate, etc.
// Calling this can require a full reinitialization of video/audio drivers in the frontend,
// so it is important to call it very sparingly, and usually only with the users explicit consent.
// An eventual driver reinit will happen so that video and audio callbacks
// happening after this call within the same retro_run() call will target the newly initialized driver.
//
// This callback makes it possible to support configurable resolutions in games, which can be useful to
// avoid setting the "worst case" in max_width/max_height.
//
// ***HIGHLY RECOMMENDED*** Do not call this callback every time resolution changes in an emulator core if it's
// expected to be a temporary change, for the reasons of possible driver reinit.
// This call is not a free pass for not trying to provide correct values in retro_get_system_av_info().
//
// If this returns false, the frontend does not acknowledge a changed av_info struct.
#define RETRO_ENVIRONMENT_SET_PROC_ADDRESS_CALLBACK 33
// const struct retro_get_proc_address_interface * --
// Allows a libretro core to announce support for the get_proc_address() interface.
// This interface allows for a standard way to extend libretro where use of environment calls are too indirect,
// e.g. for cases where the frontend wants to call directly into the core.
//
// If a core wants to expose this interface, SET_PROC_ADDRESS_CALLBACK **MUST** be called from within retro_set_environment().
//
#define RETRO_ENVIRONMENT_SET_SUBSYSTEM_INFO 34
// const struct retro_subsystem_info * --
// This environment call introduces the concept of libretro "subsystems".
// A subsystem is a variant of a libretro core which supports different kinds of games.
// The purpose of this is to support e.g. emulators which might have special needs, e.g. Super Nintendos Super GameBoy, Sufami Turbo.
// It can also be used to pick among subsystems in an explicit way if the libretro implementation is a multi-system emulator itself.
//
// Loading a game via a subsystem is done with retro_load_game_special(),
// and this environment call allows a libretro core to expose which subsystems are supported for use with retro_load_game_special().
// A core passes an array of retro_game_special_info which is terminated with a zeroed out retro_game_special_info struct.
//
// If a core wants to use this functionality, SET_SUBSYSTEM_INFO **MUST** be called from within retro_set_environment().
//
#define RETRO_ENVIRONMENT_SET_CONTROLLER_INFO 35
// const struct retro_controller_info * --
// This environment call lets a libretro core tell the frontend which
// controller types are recognized in calls to retro_set_controller_port_device().
//
// Some emulators such as Super Nintendo
// support multiple lightgun types which must be specifically selected from.
// It is therefore sometimes necessary for a frontend to be able to tell
// the core about a special kind of input device which is not covered by the
// libretro input API.
//
// In order for a frontend to understand the workings of an input device,
// it must be a specialized type
// of the generic device types already defined in the libretro API.
//
// Which devices are supported can vary per input port.
// The core must pass an array of const struct retro_controller_info which is terminated with
// a blanked out struct. Each element of the struct corresponds to an ascending port index to retro_set_controller_port_device().
// Even if special device types are set in the libretro core, libretro should only poll input based on the base input device types.
struct retro_controller_description
{
// Human-readable description of the controller. Even if using a generic input device type, this can be
// set to the particular device type the core uses.
const char *desc;
// Device type passed to retro_set_controller_port_device(). If the device type is a sub-class of a generic input device type,
// use the RETRO_DEVICE_SUBCLASS macro to create an ID. E.g. RETRO_DEVICE_SUBCLASS(RETRO_DEVICE_JOYPAD, 1).
unsigned id;
};
struct retro_controller_info
{
const struct retro_controller_description *types;
unsigned num_types;
};
struct retro_subsystem_memory_info
{
const char *extension; // The extension associated with a memory type, e.g. "psram".
unsigned type; // The memory type for retro_get_memory(). This should be at least 0x100 to avoid conflict with standardized libretro memory types.
};
struct retro_subsystem_rom_info
{
const char *desc; // Describes what the ROM is (SGB bios, GB rom, etc).
const char *valid_extensions; // Same definition as retro_get_system_info().
bool need_fullpath; // Same definition as retro_get_system_info().
bool block_extract; // Same definition as retro_get_system_info().
bool required; // This is set if the ROM is required to load a game. If this is set to false, a zeroed-out retro_game_info can be passed.
// ROMs can have multiple associated persistent memory types (retro_get_memory()).
const struct retro_subsystem_memory_info *memory;
unsigned num_memory;
};
struct retro_subsystem_info
{
const char *desc; // Human-readable string of the subsystem type, e.g. "Super GameBoy"
// A computer friendly short string identifier for the subsystem type.
// This name must be [a-z].
// E.g. if desc is "Super GameBoy", this can be "sgb".
// This identifier can be used for command-line interfaces, etc.
const char *ident;
// Infos for each ROM. The first entry is assumed to be the "most significant" ROM for frontend purposes.
// E.g. with Super GameBoy, the first ROM should be the GameBoy ROM, as it is the most "significant" ROM to a user.
// If a frontend creates new file paths based on the ROM used (e.g. savestates), it should use the path for the first ROM to do so.
const struct retro_subsystem_rom_info *roms;
unsigned num_roms; // Number of ROMs associated with a subsystem.
unsigned id; // The type passed to retro_load_game_special().
};
typedef void (*retro_proc_address_t)(void);
// libretro API extension functions:
// (None here so far).
//////
// Get a symbol from a libretro core.
// Cores should only return symbols which are actual extensions to the libretro API.
// Frontends should not use this to obtain symbols to standard libretro entry points (static linking or dlsym).
// The symbol name must be equal to the function name, e.g. if void retro_foo(void); exists, the symbol must be called "retro_foo".
// The returned function pointer must be cast to the corresponding type.
typedef retro_proc_address_t (*retro_get_proc_address_t)(const char *sym);
struct retro_get_proc_address_interface
{
retro_get_proc_address_t get_proc_address;
};
enum retro_log_level
{
RETRO_LOG_DEBUG = 0,
RETRO_LOG_INFO,
RETRO_LOG_WARN,
RETRO_LOG_ERROR,
RETRO_LOG_DUMMY = INT_MAX
};
// Logging function. Takes log level argument as well.
typedef void (*retro_log_printf_t)(enum retro_log_level level, const char *fmt, ...);
struct retro_log_callback
{
retro_log_printf_t log;
};
// Performance related functions
//
// ID values for SIMD CPU features
#define RETRO_SIMD_SSE (1 << 0)
#define RETRO_SIMD_SSE2 (1 << 1)
#define RETRO_SIMD_VMX (1 << 2)
#define RETRO_SIMD_VMX128 (1 << 3)
#define RETRO_SIMD_AVX (1 << 4)
#define RETRO_SIMD_NEON (1 << 5)
#define RETRO_SIMD_SSE3 (1 << 6)
#define RETRO_SIMD_SSSE3 (1 << 7)
#define RETRO_SIMD_MMX (1 << 8)
#define RETRO_SIMD_MMXEXT (1 << 9)
#define RETRO_SIMD_SSE4 (1 << 10)
#define RETRO_SIMD_SSE42 (1 << 11)
#define RETRO_SIMD_AVX2 (1 << 12)
#define RETRO_SIMD_VFPU (1 << 13)
#define RETRO_SIMD_PS (1 << 14)
typedef uint64_t retro_perf_tick_t;
typedef int64_t retro_time_t;
struct retro_perf_counter
{
const char *ident;
retro_perf_tick_t start;
retro_perf_tick_t total;
retro_perf_tick_t call_cnt;
bool registered;
};
// Returns current time in microseconds. Tries to use the most accurate timer available.
typedef retro_time_t (*retro_perf_get_time_usec_t)(void);
// A simple counter. Usually nanoseconds, but can also be CPU cycles.
// Can be used directly if desired (when creating a more sophisticated performance counter system).
typedef retro_perf_tick_t (*retro_perf_get_counter_t)(void);
// Returns a bit-mask of detected CPU features (RETRO_SIMD_*).
typedef uint64_t (*retro_get_cpu_features_t)(void);
// Asks frontend to log and/or display the state of performance counters.
// Performance counters can always be poked into manually as well.
typedef void (*retro_perf_log_t)(void);
// Register a performance counter.
// ident field must be set with a discrete value and other values in retro_perf_counter must be 0.
// Registering can be called multiple times. To avoid calling to frontend redundantly, you can check registered field first.
typedef void (*retro_perf_register_t)(struct retro_perf_counter *counter);
// Starts and stops a registered counter.
typedef void (*retro_perf_start_t)(struct retro_perf_counter *counter);
typedef void (*retro_perf_stop_t)(struct retro_perf_counter *counter);
// For convenience it can be useful to wrap register, start and stop in macros.
// E.g.:
// #ifdef LOG_PERFORMANCE
// #define RETRO_PERFORMANCE_INIT(perf_cb, name) static struct retro_perf_counter name = {#name}; if (!name.registered) perf_cb.perf_register(&(name))
// #define RETRO_PERFORMANCE_START(perf_cb, name) perf_cb.perf_start(&(name))
// #define RETRO_PERFORMANCE_STOP(perf_cb, name) perf_cb.perf_stop(&(name))
// #else
// ... Blank macros ...
// #endif
// These can then be used mid-functions around code snippets.
//
// extern struct retro_perf_callback perf_cb; // Somewhere in the core.
//
// void do_some_heavy_work(void)
// {
// RETRO_PERFORMANCE_INIT(cb, work_1);
// RETRO_PERFORMANCE_START(cb, work_1);
// heavy_work_1();
// RETRO_PERFORMANCE_STOP(cb, work_1);
//
// RETRO_PERFORMANCE_INIT(cb, work_2);
// RETRO_PERFORMANCE_START(cb, work_2);
// heavy_work_2();
// RETRO_PERFORMANCE_STOP(cb, work_2);
// }
//
// void retro_deinit(void)
// {
// perf_cb.perf_log(); // Log all perf counters here for example.
// }
struct retro_perf_callback
{
retro_perf_get_time_usec_t get_time_usec;
retro_get_cpu_features_t get_cpu_features;
retro_perf_get_counter_t get_perf_counter;
retro_perf_register_t perf_register;
retro_perf_start_t perf_start;
retro_perf_stop_t perf_stop;
retro_perf_log_t perf_log;
};
// FIXME: Document the sensor API and work out behavior.
// It will be marked as experimental until then.
enum retro_sensor_action
{
RETRO_SENSOR_ACCELEROMETER_ENABLE = 0,
RETRO_SENSOR_ACCELEROMETER_DISABLE,
RETRO_SENSOR_DUMMY = INT_MAX
};
// Id values for SENSOR types.
#define RETRO_SENSOR_ACCELEROMETER_X 0
#define RETRO_SENSOR_ACCELEROMETER_Y 1
#define RETRO_SENSOR_ACCELEROMETER_Z 2
typedef bool (*retro_set_sensor_state_t)(unsigned port, enum retro_sensor_action action, unsigned rate);
typedef float (*retro_sensor_get_input_t)(unsigned port, unsigned id);
struct retro_sensor_interface
{
retro_set_sensor_state_t set_sensor_state;
retro_sensor_get_input_t get_sensor_input;
};
////
enum retro_camera_buffer
{
RETRO_CAMERA_BUFFER_OPENGL_TEXTURE = 0,
RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER,
RETRO_CAMERA_BUFFER_DUMMY = INT_MAX
};
// Starts the camera driver. Can only be called in retro_run().
typedef bool (*retro_camera_start_t)(void);
// Stops the camera driver. Can only be called in retro_run().
typedef void (*retro_camera_stop_t)(void);
// Callback which signals when the camera driver is initialized and/or deinitialized.
// retro_camera_start_t can be called in initialized callback.
typedef void (*retro_camera_lifetime_status_t)(void);
// A callback for raw framebuffer data. buffer points to an XRGB8888 buffer.
// Width, height and pitch are similar to retro_video_refresh_t.
// First pixel is top-left origin.
typedef void (*retro_camera_frame_raw_framebuffer_t)(const uint32_t *buffer, unsigned width, unsigned height, size_t pitch);
// A callback for when OpenGL textures are used.
//
// texture_id is a texture owned by camera driver.
// Its state or content should be considered immutable, except for things like texture filtering and clamping.
//
// texture_target is the texture target for the GL texture.
// These can include e.g. GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE, and possibly more depending on extensions.
//
// affine points to a packed 3x3 column-major matrix used to apply an affine transform to texture coordinates. (affine_matrix * vec3(coord_x, coord_y, 1.0))
// After transform, normalized texture coord (0, 0) should be bottom-left and (1, 1) should be top-right (or (width, height) for RECTANGLE).
//
// GL-specific typedefs are avoided here to avoid relying on gl.h in the API definition.
typedef void (*retro_camera_frame_opengl_texture_t)(unsigned texture_id, unsigned texture_target, const float *affine);
struct retro_camera_callback
{
uint64_t caps; // Set by libretro core. Example bitmask: caps = (1 << RETRO_CAMERA_BUFFER_OPENGL_TEXTURE) | (1 << RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER).
unsigned width; // Desired resolution for camera. Is only used as a hint.
unsigned height;
retro_camera_start_t start; // Set by frontend.
retro_camera_stop_t stop; // Set by frontend.
retro_camera_frame_raw_framebuffer_t frame_raw_framebuffer; // Set by libretro core if raw framebuffer callbacks will be used.
retro_camera_frame_opengl_texture_t frame_opengl_texture; // Set by libretro core if OpenGL texture callbacks will be used.
// Set by libretro core. Called after camera driver is initialized and ready to be started.
// Can be NULL, in which this callback is not called.
retro_camera_lifetime_status_t initialized;
// Set by libretro core. Called right before camera driver is deinitialized.
// Can be NULL, in which this callback is not called.
retro_camera_lifetime_status_t deinitialized;
};
// Sets the interval of time and/or distance at which to update/poll location-based data.
// To ensure compatibility with all location-based implementations, values for both
// interval_ms and interval_distance should be provided.
// interval_ms is the interval expressed in milliseconds.
// interval_distance is the distance interval expressed in meters.
typedef void (*retro_location_set_interval_t)(unsigned interval_ms, unsigned interval_distance);
// Start location services. The device will start listening for changes to the
// current location at regular intervals (which are defined with retro_location_set_interval_t).
typedef bool (*retro_location_start_t)(void);
// Stop location services. The device will stop listening for changes to the current
// location.
typedef void (*retro_location_stop_t)(void);
// Get the position of the current location. Will set parameters to 0 if no new
// location update has happened since the last time.
typedef bool (*retro_location_get_position_t)(double *lat, double *lon, double *horiz_accuracy,
double *vert_accuracy);
// Callback which signals when the location driver is initialized and/or deinitialized.
// retro_location_start_t can be called in initialized callback.
typedef void (*retro_location_lifetime_status_t)(void);
struct retro_location_callback
{
retro_location_start_t start;
retro_location_stop_t stop;
retro_location_get_position_t get_position;
retro_location_set_interval_t set_interval;
retro_location_lifetime_status_t initialized;
retro_location_lifetime_status_t deinitialized;
};
enum retro_rumble_effect
{
RETRO_RUMBLE_STRONG = 0,
RETRO_RUMBLE_WEAK = 1,
RETRO_RUMBLE_DUMMY = INT_MAX
};
// Sets rumble state for joypad plugged in port 'port'. Rumble effects are controlled independently,
// and setting e.g. strong rumble does not override weak rumble.
// Strength has a range of [0, 0xffff].
//
// Returns true if rumble state request was honored. Calling this before first retro_run() is likely to return false.
typedef bool (*retro_set_rumble_state_t)(unsigned port, enum retro_rumble_effect effect, uint16_t strength);
struct retro_rumble_interface
{
retro_set_rumble_state_t set_rumble_state;
};
// Notifies libretro that audio data should be written.
typedef void (*retro_audio_callback_t)(void);
// True: Audio driver in frontend is active, and callback is expected to be called regularily.
// False: Audio driver in frontend is paused or inactive. Audio callback will not be called until set_state has been called with true.
// Initial state is false (inactive).
typedef void (*retro_audio_set_state_callback_t)(bool enabled);
struct retro_audio_callback
{
retro_audio_callback_t callback;
retro_audio_set_state_callback_t set_state;
};
// Notifies a libretro core of time spent since last invocation of retro_run() in microseconds.
// It will be called right before retro_run() every frame.
// The frontend can tamper with timing to support cases like fast-forward, slow-motion and framestepping.
// In those scenarios the reference frame time value will be used.
typedef int64_t retro_usec_t;
typedef void (*retro_frame_time_callback_t)(retro_usec_t usec);
struct retro_frame_time_callback
{
retro_frame_time_callback_t callback;
retro_usec_t reference; // Represents the time of one frame. It is computed as 1000000 / fps, but the implementation will resolve the rounding to ensure that framestepping, etc is exact.
};
// Pass this to retro_video_refresh_t if rendering to hardware.
// Passing NULL to retro_video_refresh_t is still a frame dupe as normal.
#define RETRO_HW_FRAME_BUFFER_VALID ((void*)-1)
// Invalidates the current HW context.
// Any GL state is lost, and must not be deinitialized explicitly. If explicit deinitialization is desired by the libretro core,
// it should implement context_destroy callback.
// If called, all GPU resources must be reinitialized.
// Usually called when frontend reinits video driver.
// Also called first time video driver is initialized, allowing libretro core to init resources.
typedef void (*retro_hw_context_reset_t)(void);
// Gets current framebuffer which is to be rendered to. Could change every frame potentially.
typedef uintptr_t (*retro_hw_get_current_framebuffer_t)(void);
// Get a symbol from HW context.
typedef retro_proc_address_t (*retro_hw_get_proc_address_t)(const char *sym);
enum retro_hw_context_type
{
RETRO_HW_CONTEXT_NONE = 0,
RETRO_HW_CONTEXT_OPENGL, // OpenGL 2.x. Latest version available before 3.x+. Driver can choose to use latest compatibility context.
RETRO_HW_CONTEXT_OPENGLES2, // GLES 2.0
RETRO_HW_CONTEXT_OPENGL_CORE, // Modern desktop core GL context. Use major/minor fields to set GL version.