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author3gg <3gg@shellblade.net>2025-08-30 16:53:58 -0700
committer3gg <3gg@shellblade.net>2025-08-30 16:53:58 -0700
commit6aaedb813fa11ba0679c3051bc2eb28646b9506c (patch)
tree34acbfc9840e02cb4753e6306ea7ce978bf8b58e /src/contrib/SDL-3.2.20/examples/renderer/14-viewport
parent8f228ade99dd3d4c8da9b78ade1815c9adf85c8f (diff)
Update to SDL3
Diffstat (limited to 'src/contrib/SDL-3.2.20/examples/renderer/14-viewport')
-rw-r--r--src/contrib/SDL-3.2.20/examples/renderer/14-viewport/README.txt4
-rw-r--r--src/contrib/SDL-3.2.20/examples/renderer/14-viewport/thumbnail.pngbin0 -> 146306 bytes
-rw-r--r--src/contrib/SDL-3.2.20/examples/renderer/14-viewport/viewport.c136
3 files changed, 140 insertions, 0 deletions
diff --git a/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/README.txt b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/README.txt
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+++ b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/README.txt
@@ -0,0 +1,4 @@
1This example creates an SDL window and renderer, loads a texture
2from a .bmp file, and then draws it a few times each frame, adjusting
3the viewport before each draw.
4
diff --git a/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/thumbnail.png b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/thumbnail.png
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+++ b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/thumbnail.png
Binary files differ
diff --git a/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/viewport.c b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/viewport.c
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+++ b/src/contrib/SDL-3.2.20/examples/renderer/14-viewport/viewport.c
@@ -0,0 +1,136 @@
1/*
2 * This example creates an SDL window and renderer, and then draws some
3 * textures to it every frame, adjusting the viewport.
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. */
13static SDL_Window *window = NULL;
14static SDL_Renderer *renderer = NULL;
15static SDL_Texture *texture = NULL;
16static int texture_width = 0;
17static int texture_height = 0;
18
19#define WINDOW_WIDTH 640
20#define WINDOW_HEIGHT 480
21
22/* This function runs once at startup. */
23SDL_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 Viewport", "1.0", "com.example.renderer-viewport");
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/viewport", 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. */
70SDL_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. */
79SDL_AppResult SDL_AppIterate(void *appstate)
80{
81 SDL_FRect dst_rect = { 0, 0, (float) texture_width, (float) texture_height };
82 SDL_Rect viewport;
83
84 /* Setting a viewport has the effect of limiting the area that rendering
85 can happen, and making coordinate (0, 0) live somewhere else in the
86 window. It does _not_ scale rendering to fit the viewport. */
87
88 /* as you can see from this, rendering draws over whatever was drawn before it. */
89 SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE); /* black, full alpha */
90 SDL_RenderClear(renderer); /* start with a blank canvas. */
91
92 /* Draw once with the whole window as the viewport. */
93 viewport.x = 0;
94 viewport.y = 0;
95 viewport.w = WINDOW_WIDTH / 2;
96 viewport.h = WINDOW_HEIGHT / 2;
97 SDL_SetRenderViewport(renderer, NULL); /* NULL means "use the whole window" */
98 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
99
100 /* top right quarter of the window. */
101 viewport.x = WINDOW_WIDTH / 2;
102 viewport.y = WINDOW_HEIGHT / 2;
103 viewport.w = WINDOW_WIDTH / 2;
104 viewport.h = WINDOW_HEIGHT / 2;
105 SDL_SetRenderViewport(renderer, &viewport);
106 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
107
108 /* bottom 20% of the window. Note it clips the width! */
109 viewport.x = 0;
110 viewport.y = WINDOW_HEIGHT - (WINDOW_HEIGHT / 5);
111 viewport.w = WINDOW_WIDTH / 5;
112 viewport.h = WINDOW_HEIGHT / 5;
113 SDL_SetRenderViewport(renderer, &viewport);
114 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
115
116 /* what happens if you try to draw above the viewport? It should clip! */
117 viewport.x = 100;
118 viewport.y = 200;
119 viewport.w = WINDOW_WIDTH;
120 viewport.h = WINDOW_HEIGHT;
121 SDL_SetRenderViewport(renderer, &viewport);
122 dst_rect.y = -50;
123 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
124
125 SDL_RenderPresent(renderer); /* put it all on the screen! */
126
127 return SDL_APP_CONTINUE; /* carry on with the program! */
128}
129
130/* This function runs once at shutdown. */
131void SDL_AppQuit(void *appstate, SDL_AppResult result)
132{
133 SDL_DestroyTexture(texture);
134 /* SDL will clean up the window/renderer for us. */
135}
136