diff options
author | 3gg <3gg@shellblade.net> | 2025-08-30 16:53:58 -0700 |
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committer | 3gg <3gg@shellblade.net> | 2025-08-30 16:53:58 -0700 |
commit | 6aaedb813fa11ba0679c3051bc2eb28646b9506c (patch) | |
tree | 34acbfc9840e02cb4753e6306ea7ce978bf8b58e /src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c | |
parent | 8f228ade99dd3d4c8da9b78ade1815c9adf85c8f (diff) |
Update to SDL3
Diffstat (limited to 'src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c')
-rw-r--r-- | src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c b/src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c new file mode 100644 index 0000000..bf309bc --- /dev/null +++ b/src/contrib/SDL-3.2.20/examples/renderer/07-streaming-textures/streaming-textures.c | |||
@@ -0,0 +1,109 @@ | |||
1 | /* | ||
2 | * This example creates an SDL window and renderer, and then draws a streaming | ||
3 | * texture to it every frame. | ||
4 | * | ||
5 | * This code is public domain. Feel free to use it for any purpose! | ||
6 | */ | ||
7 | |||
8 | #define SDL_MAIN_USE_CALLBACKS 1 /* use the callbacks instead of main() */ | ||
9 | #include <SDL3/SDL.h> | ||
10 | #include <SDL3/SDL_main.h> | ||
11 | |||
12 | /* We will use this renderer to draw into this window every frame. */ | ||
13 | static SDL_Window *window = NULL; | ||
14 | static SDL_Renderer *renderer = NULL; | ||
15 | static SDL_Texture *texture = NULL; | ||
16 | |||
17 | #define TEXTURE_SIZE 150 | ||
18 | |||
19 | #define WINDOW_WIDTH 640 | ||
20 | #define WINDOW_HEIGHT 480 | ||
21 | |||
22 | /* This function runs once at startup. */ | ||
23 | SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[]) | ||
24 | { | ||
25 | SDL_SetAppMetadata("Example Renderer Streaming Textures", "1.0", "com.example.renderer-streaming-textures"); | ||
26 | |||
27 | if (!SDL_Init(SDL_INIT_VIDEO)) { | ||
28 | SDL_Log("Couldn't initialize SDL: %s", SDL_GetError()); | ||
29 | return SDL_APP_FAILURE; | ||
30 | } | ||
31 | |||
32 | if (!SDL_CreateWindowAndRenderer("examples/renderer/streaming-textures", WINDOW_WIDTH, WINDOW_HEIGHT, 0, &window, &renderer)) { | ||
33 | SDL_Log("Couldn't create window/renderer: %s", SDL_GetError()); | ||
34 | return SDL_APP_FAILURE; | ||
35 | } | ||
36 | |||
37 | texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA8888, SDL_TEXTUREACCESS_STREAMING, TEXTURE_SIZE, TEXTURE_SIZE); | ||
38 | if (!texture) { | ||
39 | SDL_Log("Couldn't create streaming texture: %s", SDL_GetError()); | ||
40 | return SDL_APP_FAILURE; | ||
41 | } | ||
42 | |||
43 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
44 | } | ||
45 | |||
46 | /* This function runs when a new event (mouse input, keypresses, etc) occurs. */ | ||
47 | SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) | ||
48 | { | ||
49 | if (event->type == SDL_EVENT_QUIT) { | ||
50 | return SDL_APP_SUCCESS; /* end the program, reporting success to the OS. */ | ||
51 | } | ||
52 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
53 | } | ||
54 | |||
55 | /* This function runs once per frame, and is the heart of the program. */ | ||
56 | SDL_AppResult SDL_AppIterate(void *appstate) | ||
57 | { | ||
58 | SDL_FRect dst_rect; | ||
59 | const Uint64 now = SDL_GetTicks(); | ||
60 | SDL_Surface *surface = NULL; | ||
61 | |||
62 | /* we'll have some color move around over a few seconds. */ | ||
63 | const float direction = ((now % 2000) >= 1000) ? 1.0f : -1.0f; | ||
64 | const float scale = ((float) (((int) (now % 1000)) - 500) / 500.0f) * direction; | ||
65 | |||
66 | /* To update a streaming texture, you need to lock it first. This gets you access to the pixels. | ||
67 | Note that this is considered a _write-only_ operation: the buffer you get from locking | ||
68 | might not acutally have the existing contents of the texture, and you have to write to every | ||
69 | locked pixel! */ | ||
70 | |||
71 | /* You can use SDL_LockTexture() to get an array of raw pixels, but we're going to use | ||
72 | SDL_LockTextureToSurface() here, because it wraps that array in a temporary SDL_Surface, | ||
73 | letting us use the surface drawing functions instead of lighting up individual pixels. */ | ||
74 | if (SDL_LockTextureToSurface(texture, NULL, &surface)) { | ||
75 | SDL_Rect r; | ||
76 | SDL_FillSurfaceRect(surface, NULL, SDL_MapRGB(SDL_GetPixelFormatDetails(surface->format), NULL, 0, 0, 0)); /* make the whole surface black */ | ||
77 | r.w = TEXTURE_SIZE; | ||
78 | r.h = TEXTURE_SIZE / 10; | ||
79 | r.x = 0; | ||
80 | r.y = (int) (((float) (TEXTURE_SIZE - r.h)) * ((scale + 1.0f) / 2.0f)); | ||
81 | SDL_FillSurfaceRect(surface, &r, SDL_MapRGB(SDL_GetPixelFormatDetails(surface->format), NULL, 0, 255, 0)); /* make a strip of the surface green */ | ||
82 | SDL_UnlockTexture(texture); /* upload the changes (and frees the temporary surface)! */ | ||
83 | } | ||
84 | |||
85 | /* as you can see from this, rendering draws over whatever was drawn before it. */ | ||
86 | SDL_SetRenderDrawColor(renderer, 66, 66, 66, SDL_ALPHA_OPAQUE); /* grey, full alpha */ | ||
87 | SDL_RenderClear(renderer); /* start with a blank canvas. */ | ||
88 | |||
89 | /* Just draw the static texture a few times. You can think of it like a | ||
90 | stamp, there isn't a limit to the number of times you can draw with it. */ | ||
91 | |||
92 | /* Center this one. It'll draw the latest version of the texture we drew while it was locked. */ | ||
93 | dst_rect.x = ((float) (WINDOW_WIDTH - TEXTURE_SIZE)) / 2.0f; | ||
94 | dst_rect.y = ((float) (WINDOW_HEIGHT - TEXTURE_SIZE)) / 2.0f; | ||
95 | dst_rect.w = dst_rect.h = (float) TEXTURE_SIZE; | ||
96 | SDL_RenderTexture(renderer, texture, NULL, &dst_rect); | ||
97 | |||
98 | SDL_RenderPresent(renderer); /* put it all on the screen! */ | ||
99 | |||
100 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
101 | } | ||
102 | |||
103 | /* This function runs once at shutdown. */ | ||
104 | void SDL_AppQuit(void *appstate, SDL_AppResult result) | ||
105 | { | ||
106 | SDL_DestroyTexture(texture); | ||
107 | /* SDL will clean up the window/renderer for us. */ | ||
108 | } | ||
109 | |||