load_bmp.c

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#include <banjo/app.h>
#include <banjo/main.h>
#include <banjo/bitmap.h>
#include <banjo/event.h>
#include <banjo/log.h>
#include <banjo/memory.h>
#include <banjo/system.h>
#include <banjo/time.h>
#include <banjo/window.h>
 
bj_window* window               = 0;
bj_bitmap* bmp_sprite_sheet     = 0;
 
// Static image: just stretch-blit the loaded sprite sheet to the
// framebuffer whenever banjo asks for a paint. The user's model (the
// loaded bitmap) persists across calls.
static void on_draw(
    struct bj_window*        w,
    struct bj_render_target* target,
    const struct bj_rect*    dirty,
    void*                    user_data
) {
    (void)w; (void)dirty; (void)user_data;
    bj_blit_stretched(bmp_sprite_sheet, 0, bj_render_target_bitmap(target), 0, BJ_BLIT_OP_COPY);
}
 
static void* setup(struct bj_app* app, void* init_data) {
    (void)init_data;
 
    // Load a BMP file from disk. BANJO_ASSETS_DIR is a macro pointing to the
    // assets directory. The second parameter is an optional error pointer.
    // Returns NULL on failure (file not found, invalid format, etc.).
    bmp_sprite_sheet = bj_create_bitmap_from_file(BANJO_ASSETS_DIR"/bmp/gabe-idle-run.bmp", 0);
 
    if (!bj_begin(BJ_VIDEO_SYSTEM, 0)) {
        bj_quit_app(app, 1);
        return 0;
    }
 
    // Create a window sized to the loaded bitmap. bj_bitmap_width() and
    // bj_bitmap_height() query the dimensions. We scale by 10 for visibility
    // since the sprite sheet is small.
    window = bj_bind_window("sprite sheet - Banjo", 0, 0,
        bj_bitmap_width(bmp_sprite_sheet) * 10,
        bj_bitmap_height(bmp_sprite_sheet) * 10,
        0, 0
    );
 
    bj_set_key_callback(bj_close_on_escape, 0);
    bj_set_draw_callback(window, on_draw, 0);
    bj_invalidate_window(window);
    return 0;
}
 
static void step(struct bj_app* app, struct bj_tick_info tick, void* user_data) {
    (void)tick;
    (void)user_data;
 
    bj_dispatch_events();
 
    if (bj_should_close_window(window)) {
        bj_quit_app(app, 0);
    }
}
 
static void teardown(struct bj_app* app, void* user_data) {
    (void)user_data;
    bj_unbind_window(window);
    bj_end();
 
    // Always destroy loaded bitmaps to free memory. Do this after bj_end()
    // to ensure the bitmap isn't referenced by any Banjo subsystems.
    bj_destroy_bitmap(bmp_sprite_sheet);
}
 
int main(int argc, char* argv[]) {
    (void)argc; (void)argv;
    return bj_run_app(setup, step, 0, teardown, 0);
}