| /* |
| * 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 <SDL3/SDL.h> |
| #include <SDL3/SDL_main.h> |
| |
| /* 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 *png_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 .png into a surface, move it to a texture from there. */ |
| SDL_asprintf(&png_path, "%sgamepad_front.png", SDL_GetBasePath()); /* allocate a string of the full file path */ |
| surface = SDL_LoadPNG(png_path); |
| if (!surface) { |
| SDL_Log("Couldn't load bitmap: %s", SDL_GetError()); |
| return SDL_APP_FAILURE; |
| } |
| |
| SDL_free(png_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. */ |
| } |
