Resize Cursors SDL

resize.c

#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"
#define STBIR_NO_ALPHA_EPSILON
#define STB_IMAGE_RESIZE_IMPLEMENTATION
#include "stb_image_resize.h"

#include <stdbool.h>

#include <SDL2/SDL.h>

struct cursor_def
{
    const char *path;
    SDL_Surface *image;
    SDL_Surface *image_resized;
    SDL_Cursor *cursor;
    SDL_Cursor *cursor_resized;
};

struct cursor_def cursors[] = {
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_default.bmp"        , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_attack_default.bmp" , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_item_drop.bmp"      , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_cannot_buy.bmp"     , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_spell_team.bmp"     , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_default_enemy.bmp"  , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_test.bmp"           , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_spell_enemy.bmp"    , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_move.bmp"           , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_spell_illegal.bmp"  , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_spell_default.bmp"  , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_coach.bmp"          , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_default_team.bmp"   , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_attack_team.bmp"    , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_spell_walkto.bmp"   , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_attack_illegal.bmp" , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_learnability.bmp"   , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_inivisible.bmp"     , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_learn_ability.bmp"  , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_attack_enemy.bmp"   , NULL, NULL, NULL, NULL},
    {"/home/josh/.steam/steam/SteamApps/common/dota 2 beta/dota/resource/cursor_old/cursor_buy.bmp"            , NULL, NULL, NULL, NULL}
};

#define COUNT(X) (sizeof(X) / sizeof(0[X]))

int main(int argc, const char **argv)
{
    SDL_Init(SDL_INIT_VIDEO);

    SDL_Window *window = SDL_CreateWindow("cursor test",
            SDL_WINDOWPOS_UNDEFINED,
            SDL_WINDOWPOS_UNDEFINED,
            800, 600,
            0);

    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, 0);

    int factor = 2;

    for(int i = 0; i < COUNT(cursors); i++)
    {
        struct cursor_def *cursor_def = &cursors[i];
        int w, h, n;
        unsigned char *data = stbi_load(cursor_def->path, &w, &h, &n, 0);

        if(data == NULL)
        {
            fprintf(stderr, "failed to load image %s: %s\n", cursor_def->path, stbi_failure_reason());
            exit(1);
        }

        int ww = w * factor, hh = h * factor;

        unsigned char *resize_data = malloc(ww * hh * n);
        if(stbir_resize_uint8(data, w, h, 0, resize_data, ww, hh, 0, n) == 0)
        {
            fprintf(stderr, "failed to resize image %s\n", cursor_def->path);
            exit(1);
        }

        SDL_Surface *surface = SDL_CreateRGBSurfaceFrom(data, w, h, 32, w * 4, 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000);
        SDL_Surface *surface_resized = SDL_CreateRGBSurfaceFrom(resize_data, ww, hh, 32, ww * 4, 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000);

        SDL_Cursor *cursor = SDL_CreateColorCursor(surface, 0, 0);
        SDL_Cursor *cursor_resized = SDL_CreateColorCursor(surface_resized, 0, 0);

        printf("%p, %p, %p, %p\n", surface, surface_resized, cursor, cursor_resized);

        cursor_def->image = surface;
        cursor_def->image_resized = surface_resized;
        cursor_def->cursor = cursor;
        cursor_def->cursor_resized = cursor_resized;
    }

    bool resized = false;
    unsigned current_cursor = 0;
    bool recreate = true;

    for(;;)
    {
        SDL_Event event;
        while(SDL_PollEvent(&event))
        {
            switch(event.type)
            {
                case SDL_QUIT:
                    goto shutdown;

                case SDL_KEYDOWN:
                    switch(event.key.keysym.sym)
                    {
                        case SDLK_ESCAPE: goto shutdown;
                    };
                    break;

                case SDL_KEYUP:
                    switch(event.key.keysym.sym)
                    {
                        case SDLK_TAB:
                            current_cursor = (current_cursor + 1) % COUNT(cursors);
                            recreate = true;
                            break;
                        case SDLK_SPACE:
                            resized = !resized;
                            recreate = true;
                            break;
                    };
                    break;

                default:
                    break;
            }
        }

        struct cursor_def *cursor_def = &cursors[current_cursor];

        if(recreate)
        {
            SDL_SetCursor(resized ? cursor_def->cursor_resized : cursor_def->cursor);
            printf("CHANGED TO %s%s\n", cursor_def->path, resized ? " resized" : "");
            recreate = false;
            SDL_ShowCursor(1);
        }

        SDL_SetRenderDrawColor(renderer, 154, 206, 235, 255);
        SDL_RenderClear(renderer);
        SDL_RenderPresent(renderer);
        SDL_Delay(1);
    }

shutdown:

    return 0;
}