lg_textures.h

/*
 *      LibGame - Copyright (C) Emmanuel Thomas-Maurin 2011-2026
 *      All rights reserved
 */
 
#ifndef LG_TEXTURES_H
#define LG_TEXTURES_H
 
#define LG_FIRST_NODE_TEX_ID    500001
#define LG_INVALID_TEX_ID       500002
 
#define LG_TEX_TYPE_UNKNOWN     (-1)
 
#define LG_MAX_TEX_UNITS        256
 
#define CUBEMAP_N_FACES         6
 
#define LG_TEX_SIG              "LG_Texture"
#define LG_TEX_SIG_LEN          10
 
typedef struct __attribute__((packed)) {
        uint8_t         sig[8];         /* {0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a} */
        uint8_t         padding1[8];
        uint32_t        width;          /* Big-endian */
        uint32_t        height;         /* Big-endian */
} PNG_Header;
 
#if 0
typedef struct __attribute__((packed)) {
} JPG_Header;
#endif
 
/* TODO: specify if mipmaps were generated ? */
typedef enum {
        LG_TC_UNCOMPRESSED,     /* Never with mipmaps */
        LG_TC_DXT1,
        LG_TC_DXT3,
        LG_TC_ASTC,             /* TODO: specify block size ? */
        LG_TC_ETC1,
        LG_TC_UNKNOWN
} lg_tc_format;
 
/*
 * Actually a texture node in textures doubly-linked list
 */
typedef struct LG_Texture LG_Texture;
 
struct LG_Texture {
        uint32_t        id;                     /* Texture 'handle', set to LG_INVALID_TEX_ID if not valid */
        int32_t         unit;                   /* GL_TEXTURE0 -> GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS - 1 */
        int             type;                   /* GL_TEXTURE_2D or GL_TEXTURE_CUBE_MAP (so far ...) */
        int             w;
        int             h;
        int             tc_format;              /* lg_tc_format enum */
        LG_Path         path;
        LG_Texture      *prev;
        LG_Texture      *next;
        uint8_t         sig[LG_TEX_SIG_LEN];    /* Not NULL-terminated */
};
 
typedef struct {
        LG_Path         path[CUBEMAP_N_FACES];
} LG_CubeMap_Paths;
 
void            lg_init_textures_module();
 
void            lg_tex_set_min_filter(int);
 
void            lg_tex_set_mag_filter(int);
 
int             lg_tex_get_min_filter();
 
int             lg_tex_get_mag_filter();
 
LG_Texture      *lg_texture_new_from_data(lg_tc_format, int, LG_Path, void *, void **, size_t, int, int, int);
 
LG_Texture      *lg_texture_new_from_file(int, LG_Path, LG_CubeMap_Paths *);
 
SDL_Surface     *lg_sdl_surf_from_file(LG_Path, int, int);
 
void            *lg_compressed_texdata_from_file(LG_Path, lg_tc_format *, size_t *, int *, int *, int *);
 
zboolean        lg_test_file_extension(const char *, const char *);
 
int             lg_get_png_dims(LG_Path, int *, int *);
/*
 * === Doubly-linked list ops ===
 */
zboolean        is_lg_tex(LG_Texture *);
 
void            lg_texture_remove(LG_Texture *);
 
void            lg_texture_remove_all();
 
LG_Texture      *lg_texture_first(LG_Texture *);
 
LG_Texture      *lg_texture_last(LG_Texture *);
 
LG_Texture      *lg_texture_find_by_id(uint32_t);
 
int             lg_texture_count_nodes();
 
int             lg_texture_count_gl_tex();
 
void            lg_texture_info(const LG_Texture *);
 
void            lg_texture_info_all();
 
void            lg_texture_list_all();
/*
 * Other stuff
 */
zboolean        lg_read_pixels_from_screen(void *, Rec2Di);
 
zboolean        lg_write_pixels_to_screen(void *, const Rec2Di *);
 
void            lg_texture_unbind(LG_Texture *);
 
void            lg_tex_units_info();
 
unsigned int    lg_get_active_tex();
 
void            lg_active_tex_info();
 
void            lg_free_sdl_surf(SDL_Surface *);
 
int             lg_surf_depth(SDL_Surface *);
 
void            lg_info_out_read_framebuffer();
 
#endif /* LG_TEXTURES_H */