From 6aaedb813fa11ba0679c3051bc2eb28646b9506c Mon Sep 17 00:00:00 2001 From: 3gg <3gg@shellblade.net> Date: Sat, 30 Aug 2025 16:53:58 -0700 Subject: Update to SDL3 --- .../examples/renderer/15-cliprect/cliprect.c | 137 +++++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 src/contrib/SDL-3.2.20/examples/renderer/15-cliprect/cliprect.c (limited to 'src/contrib/SDL-3.2.20/examples/renderer/15-cliprect/cliprect.c') diff --git a/src/contrib/SDL-3.2.20/examples/renderer/15-cliprect/cliprect.c b/src/contrib/SDL-3.2.20/examples/renderer/15-cliprect/cliprect.c new file mode 100644 index 0000000..058072c --- /dev/null +++ b/src/contrib/SDL-3.2.20/examples/renderer/15-cliprect/cliprect.c @@ -0,0 +1,137 @@ +/* + * This example creates an SDL window and renderer, and then draws a scene + * to it every frame, while sliding around a clipping rectangle. + * + * This code is public domain. Feel free to use it for any purpose! + */ + +#define SDL_MAIN_USE_CALLBACKS 1 /* use the callbacks instead of main() */ +#include +#include + +#define WINDOW_WIDTH 640 +#define WINDOW_HEIGHT 480 +#define CLIPRECT_SIZE 250 +#define CLIPRECT_SPEED 200 /* pixels per second */ + +/* 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_FPoint cliprect_position; +static SDL_FPoint cliprect_direction; +static Uint64 last_time = 0; + +/* A lot of this program is examples/renderer/02-primitives, so we have a good + visual that we can slide a clip rect around. The actual new magic in here + is the SDL_SetRenderClipRect() function. */ + +/* This function runs once at startup. */ +SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[]) +{ + SDL_Surface *surface = NULL; + char *bmp_path = NULL; + + SDL_SetAppMetadata("Example Renderer Clipping Rectangle", "1.0", "com.example.renderer-cliprect"); + + if (!SDL_Init(SDL_INIT_VIDEO)) { + SDL_Log("Couldn't initialize SDL: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + if (!SDL_CreateWindowAndRenderer("examples/renderer/cliprect", WINDOW_WIDTH, WINDOW_HEIGHT, 0, &window, &renderer)) { + SDL_Log("Couldn't create window/renderer: %s", SDL_GetError()); + return SDL_APP_FAILURE; + } + + cliprect_direction.x = cliprect_direction.y = 1.0f; + + last_time = SDL_GetTicks(); + + /* 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, "%ssample.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. */ + } + 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 SDL_Rect cliprect = { (int) SDL_roundf(cliprect_position.x), (int) SDL_roundf(cliprect_position.y), CLIPRECT_SIZE, CLIPRECT_SIZE }; + const Uint64 now = SDL_GetTicks(); + const float elapsed = ((float) (now - last_time)) / 1000.0f; /* seconds since last iteration */ + const float distance = elapsed * CLIPRECT_SPEED; + + /* Set a new clipping rectangle position */ + cliprect_position.x += distance * cliprect_direction.x; + if (cliprect_position.x < 0.0f) { + cliprect_position.x = 0.0f; + cliprect_direction.x = 1.0f; + } else if (cliprect_position.x >= (WINDOW_WIDTH - CLIPRECT_SIZE)) { + cliprect_position.x = (WINDOW_WIDTH - CLIPRECT_SIZE) - 1; + cliprect_direction.x = -1.0f; + } + + cliprect_position.y += distance * cliprect_direction.y; + if (cliprect_position.y < 0.0f) { + cliprect_position.y = 0.0f; + cliprect_direction.y = 1.0f; + } else if (cliprect_position.y >= (WINDOW_HEIGHT - CLIPRECT_SIZE)) { + cliprect_position.y = (WINDOW_HEIGHT - CLIPRECT_SIZE) - 1; + cliprect_direction.y = -1.0f; + } + SDL_SetRenderClipRect(renderer, &cliprect); + + last_time = now; + + /* okay, now draw! */ + + /* Note that SDL_RenderClear is _not_ affected by the clipping rectangle! */ + SDL_SetRenderDrawColor(renderer, 33, 33, 33, SDL_ALPHA_OPAQUE); /* grey, full alpha */ + SDL_RenderClear(renderer); /* start with a blank canvas. */ + + /* stretch the texture across the entire window. Only the piece in the + clipping rectangle will actually render, though! */ + SDL_RenderTexture(renderer, texture, NULL, NULL); + + SDL_RenderPresent(renderer); /* put it all on the screen! */ + + 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 will clean up the window/renderer for us. */ +} + -- cgit v1.2.3