diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt index fa4ad4dc29..2a1196f1bb 100644 --- a/examples/CMakeLists.txt +++ b/examples/CMakeLists.txt @@ -149,6 +149,7 @@ add_sdl_example_executable(audio-multiple-streams SOURCES audio/04-multiple-stre add_sdl_example_executable(audio-planar-data SOURCES audio/05-planar-data/planar-data.c) add_sdl_example_executable(input-joystick-polling SOURCES input/01-joystick-polling/joystick-polling.c) add_sdl_example_executable(input-joystick-events SOURCES input/02-joystick-events/joystick-events.c) +add_sdl_example_executable(input-gamepad-polling SOURCES input/03-gamepad-polling/gamepad-polling.c DATAFILES ${CMAKE_CURRENT_SOURCE_DIR}/../test/gamepad_front.bmp) add_sdl_example_executable(camera-read-and-draw SOURCES camera/01-read-and-draw/read-and-draw.c) add_sdl_example_executable(pen-drawing-lines SOURCES pen/01-drawing-lines/drawing-lines.c) add_sdl_example_executable(asyncio-load-bitmaps SOURCES asyncio/01-load-bitmaps/load-bitmaps.c DATAFILES ${CMAKE_CURRENT_SOURCE_DIR}/../test/sample.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/gamepad_front.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/speaker.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/icon2x.bmp) diff --git a/examples/input/03-gamepad-polling/README.txt b/examples/input/03-gamepad-polling/README.txt new file mode 100644 index 0000000000..3d5fad4707 --- /dev/null +++ b/examples/input/03-gamepad-polling/README.txt @@ -0,0 +1,3 @@ +This example code looks for the current gamepad state once per frame, +and draws a visual representation of it. See 01-joystick-polling for the +equivalent example code for the lower-level joystick API. \ No newline at end of file diff --git a/examples/input/03-gamepad-polling/gamepad-polling.c b/examples/input/03-gamepad-polling/gamepad-polling.c new file mode 100644 index 0000000000..bf2685d692 --- /dev/null +++ b/examples/input/03-gamepad-polling/gamepad-polling.c @@ -0,0 +1,221 @@ +/* + * This example code looks for the current gamepad state once per frame, + * and draws a visual representation of it. See 01-joystick-polling for the + * equivalent example code for the lower-level joystick API. + * + * This code is public domain. Feel free to use it for any purpose! + */ + +/* Joysticks are low-level interfaces: there's something with a bunch of + buttons, axes and hats, in no understood order or position. This is + a flexible interface, but you'll need to build some sort of configuration + UI to let people tell you what button, etc, does what. On top of this + interface, SDL offers the "gamepad" API, which works with lots of devices, + and knows how to map arbitrary buttons and such to look like an + Xbox/PlayStation/etc gamepad. This is easier, and better, for many games, + but isn't necessarily a good fit for complex apps and hardware. A flight + simulator, a realistic racing game, etc, might want the joystick interface + instead of gamepads. */ + +/* SDL can handle multiple gamepads, but for simplicity, this program only + deals with the first gamepad it sees. */ + +#define SDL_MAIN_USE_CALLBACKS 1 /* use the callbacks instead of main() */ +#include +#include + +/* We will use this renderer to draw into this window every frame. */ +static SDL_Window *window = NULL; +static SDL_Renderer *renderer = NULL; +static SDL_Texture *texture = NULL; +static SDL_Gamepad *gamepad = NULL; + +#define WINDOW_WIDTH 640 +#define WINDOW_HEIGHT 480 + +/* This function runs once at startup. */ +SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[]) +{ + char *bmp_path = NULL; + SDL_Surface *surface = NULL; + + SDL_SetAppMetadata("Example Input Gamepad Polling", "1.0", "com.example.input-gamepad-polling"); + + if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD)) { + SDL_Log("Couldn't initialize SDL: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + if (!SDL_CreateWindowAndRenderer("examples/input/gamepad-polling", WINDOW_WIDTH, WINDOW_HEIGHT, SDL_WINDOW_RESIZABLE, &window, &renderer)) { + SDL_Log("Couldn't create window/renderer: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + if (!SDL_SetRenderLogicalPresentation(renderer, WINDOW_WIDTH, WINDOW_HEIGHT, SDL_LOGICAL_PRESENTATION_STRETCH)) { + return SDL_APP_FAILURE; + } + + /* Textures are pixel data that we upload to the video hardware for fast drawing. Lots of 2D + engines refer to these as "sprites." We'll do a static texture (upload once, draw many + times) with data from a bitmap file. */ + + /* SDL_Surface is pixel data the CPU can access. SDL_Texture is pixel data the GPU can access. + Load a .bmp into a surface, move it to a texture from there. */ + SDL_asprintf(&bmp_path, "%sgamepad_front.bmp", SDL_GetBasePath()); /* allocate a string of the full file path */ + surface = SDL_LoadBMP(bmp_path); + if (!surface) { + SDL_Log("Couldn't load bitmap: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + SDL_free(bmp_path); /* done with this, the file is loaded. */ + + texture = SDL_CreateTextureFromSurface(renderer, surface); + if (!texture) { + SDL_Log("Couldn't create static texture: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + SDL_DestroySurface(surface); /* done with this, the texture has a copy of the pixels now. */ + + return SDL_APP_CONTINUE; /* carry on with the program! */ +} + +/* This function runs when a new event (mouse input, keypresses, etc) occurs. */ +SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) +{ + if (event->type == SDL_EVENT_QUIT) { + return SDL_APP_SUCCESS; /* end the program, reporting success to the OS. */ + } else if (event->type == SDL_EVENT_GAMEPAD_ADDED) { + /* this event is sent for each hotplugged gamepad, but also each already-connected gamepad during SDL_Init(). */ + if (gamepad == NULL) { /* we don't have a stick yet and one was added, open it! */ + gamepad = SDL_OpenGamepad(event->gdevice.which); + if (!gamepad) { + SDL_Log("Failed to open gamepad ID %u: %s", (unsigned int) event->gdevice.which, SDL_GetError()); + } + } + } else if (event->type == SDL_EVENT_GAMEPAD_REMOVED) { + if (gamepad && (SDL_GetGamepadID(gamepad) == event->gdevice.which)) { + SDL_CloseGamepad(gamepad); /* our controller was unplugged. */ + gamepad = NULL; + } + } + return SDL_APP_CONTINUE; /* carry on with the program! */ +} + +/* This function runs once per frame, and is the heart of the program. */ +SDL_AppResult SDL_AppIterate(void *appstate) +{ + const char *text = "Plug in a gamepad, please."; + static Uint64 leftthumblast = 0xFFFFFFFF; + static Uint64 rightthumblast = 0xFFFFFFFF; + const Uint64 now = SDL_GetTicks(); + Sint16 axis_x, axis_y; + float x, y; + int i; + + if (gamepad) { /* we have a stick opened? */ + text = SDL_GetGamepadName(gamepad); + } + + SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0xFF, 0xFF); /* white */ + SDL_RenderClear(renderer); + + /* note that you can get input as events, instead of polling, which is + better since it won't miss button presses if the system is lagging, + but often times checking the current state per-frame is good enough, + and maybe better if you'd rather _drop_ inputs due to lag. */ + + if (gamepad) { /* we have a stick opened? */ + /* where to draw the buttons */ + const SDL_FRect buttons[] = { + { 497, 266, 38, 38 }, /* SDL_GAMEPAD_BUTTON_SOUTH */ + { 550, 217, 38, 38 }, /* SDL_GAMEPAD_BUTTON_EAST */ + { 445, 221, 38, 38 }, /* SDL_GAMEPAD_BUTTON_WEST */ + { 499, 173, 38, 38 }, /* SDL_GAMEPAD_BUTTON_NORTH */ + { 235, 228, 32, 29 }, /* SDL_GAMEPAD_BUTTON_BACK */ + { 287, 195, 69, 69 }, /* SDL_GAMEPAD_BUTTON_GUIDE */ + { 377, 228, 32, 29 }, /* SDL_GAMEPAD_BUTTON_START */ + { 91, 234, 63, 63 }, /* SDL_GAMEPAD_BUTTON_LEFT_STICK */ + { 381, 354, 63, 63 }, /* SDL_GAMEPAD_BUTTON_RIGHT_STICK */ + { 74, 73, 102, 29 }, /* SDL_GAMEPAD_BUTTON_LEFT_SHOULDER */ + { 468, 73, 102, 29 }, /* SDL_GAMEPAD_BUTTON_RIGHT_SHOULDER */ + { 207, 316, 32, 32 }, /* SDL_GAMEPAD_BUTTON_DPAD_UP */ + { 207, 384, 32, 32 }, /* SDL_GAMEPAD_BUTTON_DPAD_DOWN */ + { 173, 351, 32, 32 }, /* SDL_GAMEPAD_BUTTON_DPAD_LEFT */ + { 242, 351, 32, 32 }, /* SDL_GAMEPAD_BUTTON_DPAD_RIGHT */ + { 310, 286, 23, 27 }, /* SDL_GAMEPAD_BUTTON_MISC1 */ + /* there are other buttons: paddles on the back of the gamepad, touchpads, etc, but this is good enough for now. */ + }; + + SDL_RenderTexture(renderer, texture, NULL, NULL); /* draw the gamepad picture to the whole window. */ + + /* draw green boxes over buttons that are currently pressed. */ + SDL_SetRenderDrawColor(renderer, 0x00, 0xFF, 0x00, 0xFF); /* green */ + for (i = 0; i < SDL_arraysize(buttons); i++) { + if (SDL_GetGamepadButton(gamepad, (SDL_GamepadButton) i)) { + SDL_RenderFillRect(renderer, &buttons[i]); + } + } + + SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0x00, 0xFF); /* yellow */ + + /* left thumb axis. */ + axis_x = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_LEFTX); + axis_y = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_LEFTY); + if ((SDL_abs(axis_x) > 1000) || (SDL_abs(axis_y) > 1000)) { /* zero means centered, but it might be a little off zero... */ + leftthumblast = now; /* keep drawing, we're still moving. */ + } + if ((now - leftthumblast) < 500) { /* draw if there was movement in the last half-second. */ + const SDL_FRect box = { 107 + ((axis_x / 32767.0f) * 30.0f), 252 + ((axis_y / 32767.0f) * 30.0f), 30, 30 }; + SDL_RenderFillRect(renderer, &box); + } + + /* right thumb axis. */ + axis_x = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_RIGHTX); + axis_y = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_RIGHTY); + if ((SDL_abs(axis_x) > 1000) || (SDL_abs(axis_y) > 1000)) { /* zero means centered, but it might be a little off zero... */ + rightthumblast = now; /* keep drawing, we're still moving. */ + } + if ((now - rightthumblast) < 500) { /* draw if there was movement in the last half-second. */ + const SDL_FRect box = { 397 + ((axis_x / 32767.0f) * 30.0f), 370 + ((axis_y / 32767.0f) * 30.0f), 30, 30 }; + SDL_RenderFillRect(renderer, &box); + } + + /* left trigger. */ + axis_y = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_LEFT_TRIGGER); + if (axis_y > 1000) { /* zero means unpressed, but it might be a little off zero... */ + const float height = ((axis_y / 32767.0f) * 65.0f); + const SDL_FRect box = { 127, 1 + (65.0f - height), 37, height }; + SDL_RenderFillRect(renderer, &box); + } + + /* right trigger. */ + axis_y = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_RIGHT_TRIGGER); + if (axis_y > 1000) { /* zero means unpressed, but it might be a little off zero... */ + const float height = ((axis_y / 32767.0f) * 65.0f); + const SDL_FRect box = { 481, 1 + (65.0f - height), 37, height }; + SDL_RenderFillRect(renderer, &box); + } + } + + x = (((float) WINDOW_WIDTH) - (SDL_strlen(text) * SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE)) / 2.0f; + if (gamepad) { + y = (float) (WINDOW_HEIGHT - (SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE + 2)); + } else { + y = (((float) WINDOW_HEIGHT) - SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE) / 2.0f; + } + SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0xFF, 0xFF); /* blue */ + SDL_RenderDebugText(renderer, x, y, text); + SDL_RenderPresent(renderer); + + return SDL_APP_CONTINUE; /* carry on with the program! */ +} + +/* This function runs once at shutdown. */ +void SDL_AppQuit(void *appstate, SDL_AppResult result) +{ + SDL_DestroyTexture(texture); + SDL_CloseGamepad(gamepad); + /* SDL will clean up the window/renderer for us. */ +} diff --git a/examples/input/03-gamepad-polling/onmouseover.webp b/examples/input/03-gamepad-polling/onmouseover.webp new file mode 100644 index 0000000000..91c7bb0dca Binary files /dev/null and b/examples/input/03-gamepad-polling/onmouseover.webp differ diff --git a/examples/input/03-gamepad-polling/thumbnail.png b/examples/input/03-gamepad-polling/thumbnail.png new file mode 100644 index 0000000000..c5bc6e6431 Binary files /dev/null and b/examples/input/03-gamepad-polling/thumbnail.png differ