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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/10-geometry/geometry.c | |
parent | 8f228ade99dd3d4c8da9b78ade1815c9adf85c8f (diff) |
Update to SDL3
Diffstat (limited to 'src/contrib/SDL-3.2.20/examples/renderer/10-geometry/geometry.c')
-rw-r--r-- | src/contrib/SDL-3.2.20/examples/renderer/10-geometry/geometry.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/src/contrib/SDL-3.2.20/examples/renderer/10-geometry/geometry.c b/src/contrib/SDL-3.2.20/examples/renderer/10-geometry/geometry.c new file mode 100644 index 0000000..77ff863 --- /dev/null +++ b/src/contrib/SDL-3.2.20/examples/renderer/10-geometry/geometry.c | |||
@@ -0,0 +1,166 @@ | |||
1 | /* | ||
2 | * This example creates an SDL window and renderer, and then draws some | ||
3 | * geometry (arbitrary polygons) 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 | static int texture_width = 0; | ||
17 | static int texture_height = 0; | ||
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_Surface *surface = NULL; | ||
26 | char *bmp_path = NULL; | ||
27 | |||
28 | SDL_SetAppMetadata("Example Renderer Geometry", "1.0", "com.example.renderer-geometry"); | ||
29 | |||
30 | if (!SDL_Init(SDL_INIT_VIDEO)) { | ||
31 | SDL_Log("Couldn't initialize SDL: %s", SDL_GetError()); | ||
32 | return SDL_APP_FAILURE; | ||
33 | } | ||
34 | |||
35 | if (!SDL_CreateWindowAndRenderer("examples/renderer/geometry", WINDOW_WIDTH, WINDOW_HEIGHT, 0, &window, &renderer)) { | ||
36 | SDL_Log("Couldn't create window/renderer: %s", SDL_GetError()); | ||
37 | return SDL_APP_FAILURE; | ||
38 | } | ||
39 | |||
40 | /* Textures are pixel data that we upload to the video hardware for fast drawing. Lots of 2D | ||
41 | engines refer to these as "sprites." We'll do a static texture (upload once, draw many | ||
42 | times) with data from a bitmap file. */ | ||
43 | |||
44 | /* SDL_Surface is pixel data the CPU can access. SDL_Texture is pixel data the GPU can access. | ||
45 | Load a .bmp into a surface, move it to a texture from there. */ | ||
46 | SDL_asprintf(&bmp_path, "%ssample.bmp", SDL_GetBasePath()); /* allocate a string of the full file path */ | ||
47 | surface = SDL_LoadBMP(bmp_path); | ||
48 | if (!surface) { | ||
49 | SDL_Log("Couldn't load bitmap: %s", SDL_GetError()); | ||
50 | return SDL_APP_FAILURE; | ||
51 | } | ||
52 | |||
53 | SDL_free(bmp_path); /* done with this, the file is loaded. */ | ||
54 | |||
55 | texture_width = surface->w; | ||
56 | texture_height = surface->h; | ||
57 | |||
58 | texture = SDL_CreateTextureFromSurface(renderer, surface); | ||
59 | if (!texture) { | ||
60 | SDL_Log("Couldn't create static texture: %s", SDL_GetError()); | ||
61 | return SDL_APP_FAILURE; | ||
62 | } | ||
63 | |||
64 | SDL_DestroySurface(surface); /* done with this, the texture has a copy of the pixels now. */ | ||
65 | |||
66 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
67 | } | ||
68 | |||
69 | /* This function runs when a new event (mouse input, keypresses, etc) occurs. */ | ||
70 | SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) | ||
71 | { | ||
72 | if (event->type == SDL_EVENT_QUIT) { | ||
73 | return SDL_APP_SUCCESS; /* end the program, reporting success to the OS. */ | ||
74 | } | ||
75 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
76 | } | ||
77 | |||
78 | /* This function runs once per frame, and is the heart of the program. */ | ||
79 | SDL_AppResult SDL_AppIterate(void *appstate) | ||
80 | { | ||
81 | const Uint64 now = SDL_GetTicks(); | ||
82 | |||
83 | /* we'll have the triangle grow and shrink over a few seconds. */ | ||
84 | const float direction = ((now % 2000) >= 1000) ? 1.0f : -1.0f; | ||
85 | const float scale = ((float) (((int) (now % 1000)) - 500) / 500.0f) * direction; | ||
86 | const float size = 200.0f + (200.0f * scale); | ||
87 | |||
88 | SDL_Vertex vertices[4]; | ||
89 | int i; | ||
90 | |||
91 | /* as you can see from this, rendering draws over whatever was drawn before it. */ | ||
92 | SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE); /* black, full alpha */ | ||
93 | SDL_RenderClear(renderer); /* start with a blank canvas. */ | ||
94 | |||
95 | /* Draw a single triangle with a different color at each vertex. Center this one and make it grow and shrink. */ | ||
96 | /* You always draw triangles with this, but you can string triangles together to form polygons. */ | ||
97 | SDL_zeroa(vertices); | ||
98 | vertices[0].position.x = ((float) WINDOW_WIDTH) / 2.0f; | ||
99 | vertices[0].position.y = (((float) WINDOW_HEIGHT) - size) / 2.0f; | ||
100 | vertices[0].color.r = 1.0f; | ||
101 | vertices[0].color.a = 1.0f; | ||
102 | vertices[1].position.x = (((float) WINDOW_WIDTH) + size) / 2.0f; | ||
103 | vertices[1].position.y = (((float) WINDOW_HEIGHT) + size) / 2.0f; | ||
104 | vertices[1].color.g = 1.0f; | ||
105 | vertices[1].color.a = 1.0f; | ||
106 | vertices[2].position.x = (((float) WINDOW_WIDTH) - size) / 2.0f; | ||
107 | vertices[2].position.y = (((float) WINDOW_HEIGHT) + size) / 2.0f; | ||
108 | vertices[2].color.b = 1.0f; | ||
109 | vertices[2].color.a = 1.0f; | ||
110 | |||
111 | SDL_RenderGeometry(renderer, NULL, vertices, 3, NULL, 0); | ||
112 | |||
113 | /* you can also map a texture to the geometry! Texture coordinates go from 0.0f to 1.0f. That will be the location | ||
114 | in the texture bound to this vertex. */ | ||
115 | SDL_zeroa(vertices); | ||
116 | vertices[0].position.x = 10.0f; | ||
117 | vertices[0].position.y = 10.0f; | ||
118 | vertices[0].color.r = vertices[0].color.g = vertices[0].color.b = vertices[0].color.a = 1.0f; | ||
119 | vertices[0].tex_coord.x = 0.0f; | ||
120 | vertices[0].tex_coord.y = 0.0f; | ||
121 | vertices[1].position.x = 150.0f; | ||
122 | vertices[1].position.y = 10.0f; | ||
123 | vertices[1].color.r = vertices[1].color.g = vertices[1].color.b = vertices[1].color.a = 1.0f; | ||
124 | vertices[1].tex_coord.x = 1.0f; | ||
125 | vertices[1].tex_coord.y = 0.0f; | ||
126 | vertices[2].position.x = 10.0f; | ||
127 | vertices[2].position.y = 150.0f; | ||
128 | vertices[2].color.r = vertices[2].color.g = vertices[2].color.b = vertices[2].color.a = 1.0f; | ||
129 | vertices[2].tex_coord.x = 0.0f; | ||
130 | vertices[2].tex_coord.y = 1.0f; | ||
131 | SDL_RenderGeometry(renderer, texture, vertices, 3, NULL, 0); | ||
132 | |||
133 | /* Did that only draw half of the texture? You can do multiple triangles sharing some vertices, | ||
134 | using indices, to get the whole thing on the screen: */ | ||
135 | |||
136 | /* Let's just move this over so it doesn't overlap... */ | ||
137 | for (i = 0; i < 3; i++) { | ||
138 | vertices[i].position.x += 450; | ||
139 | } | ||
140 | |||
141 | /* we need one more vertex, since the two triangles can share two of them. */ | ||
142 | vertices[3].position.x = 600.0f; | ||
143 | vertices[3].position.y = 150.0f; | ||
144 | vertices[3].color.r = vertices[3].color.g = vertices[3].color.b = vertices[3].color.a = 1.0f; | ||
145 | vertices[3].tex_coord.x = 1.0f; | ||
146 | vertices[3].tex_coord.y = 1.0f; | ||
147 | |||
148 | /* And an index to tell it to reuse some of the vertices between triangles... */ | ||
149 | { | ||
150 | /* 4 vertices, but 6 actual places they used. Indices need less bandwidth to transfer and can reorder vertices easily! */ | ||
151 | const int indices[] = { 0, 1, 2, 1, 2, 3 }; | ||
152 | SDL_RenderGeometry(renderer, texture, vertices, 4, indices, SDL_arraysize(indices)); | ||
153 | } | ||
154 | |||
155 | SDL_RenderPresent(renderer); /* put it all on the screen! */ | ||
156 | |||
157 | return SDL_APP_CONTINUE; /* carry on with the program! */ | ||
158 | } | ||
159 | |||
160 | /* This function runs once at shutdown. */ | ||
161 | void SDL_AppQuit(void *appstate, SDL_AppResult result) | ||
162 | { | ||
163 | SDL_DestroyTexture(texture); | ||
164 | /* SDL will clean up the window/renderer for us. */ | ||
165 | } | ||
166 | |||