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author3gg <3gg@shellblade.net>2026-03-06 13:26:57 -0800
committer3gg <3gg@shellblade.net>2026-03-06 13:26:57 -0800
commitf5c89b3bd5d74849757fd5b4d1a300068522a3ca (patch)
treed6f6e4c81745b393d7594b334710f30c0b2df3bd /SDL-3.2.8/examples/renderer/11-color-mods
Initial commitHEADmain
Diffstat (limited to 'SDL-3.2.8/examples/renderer/11-color-mods')
-rw-r--r--SDL-3.2.8/examples/renderer/11-color-mods/README.txt3
-rw-r--r--SDL-3.2.8/examples/renderer/11-color-mods/color-mods.c134
-rw-r--r--SDL-3.2.8/examples/renderer/11-color-mods/onmouseover.webpbin0 -> 278286 bytes
-rw-r--r--SDL-3.2.8/examples/renderer/11-color-mods/thumbnail.pngbin0 -> 122439 bytes
4 files changed, 137 insertions, 0 deletions
diff --git a/SDL-3.2.8/examples/renderer/11-color-mods/README.txt b/SDL-3.2.8/examples/renderer/11-color-mods/README.txt
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@@ -0,0 +1,3 @@
1This example creates an SDL window and renderer, loads a texture from a
2.bmp file, and then draws it a few times each frame, adjusting the colors.
3
diff --git a/SDL-3.2.8/examples/renderer/11-color-mods/color-mods.c b/SDL-3.2.8/examples/renderer/11-color-mods/color-mods.c
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+++ b/SDL-3.2.8/examples/renderer/11-color-mods/color-mods.c
@@ -0,0 +1,134 @@
1/*
2 * This example creates an SDL window and renderer, and then draws some
3 * textures to it every frame, adjusting their color.
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 Color Mods", "1.0", "com.example.renderer-color-mods");
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/color-mods", 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;
82 const double now = ((double)SDL_GetTicks()) / 1000.0; /* convert from milliseconds to seconds. */
83 /* choose the modulation values for the center texture. The sine wave trick makes it fade between colors smoothly. */
84 const float red = (float) (0.5 + 0.5 * SDL_sin(now));
85 const float green = (float) (0.5 + 0.5 * SDL_sin(now + SDL_PI_D * 2 / 3));
86 const float blue = (float) (0.5 + 0.5 * SDL_sin(now + SDL_PI_D * 4 / 3));
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 /* Just draw the static texture a few times. You can think of it like a
93 stamp, there isn't a limit to the number of times you can draw with it. */
94
95 /* Color modulation multiplies each pixel's red, green, and blue intensities by the mod values,
96 so multiplying by 1.0f will leave a color intensity alone, 0.0f will shut off that color
97 completely, etc. */
98
99 /* top left; let's make this one blue! */
100 dst_rect.x = 0.0f;
101 dst_rect.y = 0.0f;
102 dst_rect.w = (float) texture_width;
103 dst_rect.h = (float) texture_height;
104 SDL_SetTextureColorModFloat(texture, 0.0f, 0.0f, 1.0f); /* kill all red and green. */
105 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
106
107 /* center this one, and have it cycle through red/green/blue modulations. */
108 dst_rect.x = ((float) (WINDOW_WIDTH - texture_width)) / 2.0f;
109 dst_rect.y = ((float) (WINDOW_HEIGHT - texture_height)) / 2.0f;
110 dst_rect.w = (float) texture_width;
111 dst_rect.h = (float) texture_height;
112 SDL_SetTextureColorModFloat(texture, red, green, blue);
113 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
114
115 /* bottom right; let's make this one red! */
116 dst_rect.x = (float) (WINDOW_WIDTH - texture_width);
117 dst_rect.y = (float) (WINDOW_HEIGHT - texture_height);
118 dst_rect.w = (float) texture_width;
119 dst_rect.h = (float) texture_height;
120 SDL_SetTextureColorModFloat(texture, 1.0f, 0.0f, 0.0f); /* kill all green and blue. */
121 SDL_RenderTexture(renderer, texture, NULL, &dst_rect);
122
123 SDL_RenderPresent(renderer); /* put it all on the screen! */
124
125 return SDL_APP_CONTINUE; /* carry on with the program! */
126}
127
128/* This function runs once at shutdown. */
129void SDL_AppQuit(void *appstate, SDL_AppResult result)
130{
131 SDL_DestroyTexture(texture);
132 /* SDL will clean up the window/renderer for us. */
133}
134
diff --git a/SDL-3.2.8/examples/renderer/11-color-mods/onmouseover.webp b/SDL-3.2.8/examples/renderer/11-color-mods/onmouseover.webp
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+++ b/SDL-3.2.8/examples/renderer/11-color-mods/onmouseover.webp
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diff --git a/SDL-3.2.8/examples/renderer/11-color-mods/thumbnail.png b/SDL-3.2.8/examples/renderer/11-color-mods/thumbnail.png
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