/*

SDL_image: An example image loading library for use with SDL

Copyright (C) 1997-2009 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public

License as published by the Free Software Foundation; either

version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this library; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Sam Lantinga

slouken@libsdl.org

*/

/* This is a XCF image file loading framework */

#include <stdio.h>

#include <ctype.h>

#include <string.h>

#include <stdlib.h>

#include "SDL_endian.h"

#include "SDL_image.h"

#ifdef LOAD_XCF

#if DEBUG

static char prop_names [][30] = {

"end",

"colormap",

"active_layer",

"active_channel",

"selection",

"floating_selection",

"opacity",

"mode",

"visible",

"linked",

"preserve_transparency",

"apply_mask",

"edit_mask",

"show_mask",

"show_masked",

"offsets",

"color",

"compression",

"guides",

"resolution",

"tattoo",

"parasites",

"unit",

"paths",

"user_unit"

};

#endif

typedef enum

{

PROP_END = 0,

PROP_COLORMAP = 1,

PROP_ACTIVE_LAYER = 2,

PROP_ACTIVE_CHANNEL = 3,

PROP_SELECTION = 4,

PROP_FLOATING_SELECTION = 5,

PROP_OPACITY = 6,

PROP_MODE = 7,

PROP_VISIBLE = 8,

PROP_LINKED = 9,

PROP_PRESERVE_TRANSPARENCY = 10,

PROP_APPLY_MASK = 11,

PROP_EDIT_MASK = 12,

PROP_SHOW_MASK = 13,

PROP_SHOW_MASKED = 14,

PROP_OFFSETS = 15,

PROP_COLOR = 16,

PROP_COMPRESSION = 17,

PROP_GUIDES = 18,

PROP_RESOLUTION = 19,

PROP_TATTOO = 20,

PROP_PARASITES = 21,

PROP_UNIT = 22,

PROP_PATHS = 23,

PROP_USER_UNIT = 24

} xcf_prop_type;

typedef enum {

COMPR_NONE = 0,

COMPR_RLE = 1,

COMPR_ZLIB = 2,

COMPR_FRACTAL = 3

} xcf_compr_type;

typedef enum {

IMAGE_RGB = 0,

IMAGE_GREYSCALE = 1,

IMAGE_INDEXED = 2

} xcf_image_type;

typedef struct {

Uint32 id;

Uint32 length;

union {

struct {

Uint32 num;

char * cmap;

} colormap; // 1

struct {

Uint32 drawable_offset;

} floating_selection; // 5

Sint32 opacity;

Sint32 mode;

int visible;

int linked;

int preserve_transparency;

int apply_mask;

int show_mask;

struct {

Sint32 x;

Sint32 y;

} offset;

unsigned char color [3];

Uint8 compression;

struct {

Sint32 x;

Sint32 y;

} resolution;

struct {

char * name;

Uint32 flags;

Uint32 size;

char * data;

} parasite;

} data;

} xcf_prop;

typedef struct {

char sign [14];

Uint32 width;

Uint32 height;

Sint32 image_type;

xcf_prop * properties;

Uint32 * layer_file_offsets;

Uint32 * channel_file_offsets;

xcf_compr_type compr;

Uint32 cm_num;

unsigned char * cm_map;

} xcf_header;

typedef struct {

Uint32 width;

Uint32 height;

Sint32 layer_type;

char * name;

xcf_prop * properties;

Uint32 hierarchy_file_offset;

Uint32 layer_mask_offset;

Uint32 offset_x;

Uint32 offset_y;

int visible;

} xcf_layer;

typedef struct {

Uint32 width;

Uint32 height;

char * name;

xcf_prop * properties;

Uint32 hierarchy_file_offset;

Uint32 color;

Uint32 opacity;

int selection;

int visible;

} xcf_channel;

typedef struct {

Uint32 width;

Uint32 height;

Uint32 bpp;

Uint32 * level_file_offsets;

} xcf_hierarchy;

typedef struct {

Uint32 width;

Uint32 height;

Uint32 * tile_file_offsets;

} xcf_level;

typedef unsigned char * xcf_tile;

typedef unsigned char * (* load_tile_type) (SDL_RWops *, Uint32, int, int, int);

/* See if an image is contained in a data source */

int IMG_isXCF(SDL_RWops *src)

{

int start;

int is_XCF;

char magic[14];

if ( !src )

return 0;

start = SDL_RWtell(src);

is_XCF = 0;

if ( SDL_RWread(src, magic, sizeof(magic), 1) ) {

if (strncmp(magic, "gimp xcf ", 9) == 0) {

is_XCF = 1;

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_XCF);

}

static char * read_string (SDL_RWops * src) {

Uint32 tmp;

char * data;

tmp = SDL_ReadBE32 (src);

if (tmp > 0) {

data = (char *) malloc (sizeof (char) * tmp);

SDL_RWread (src, data, tmp, 1);

}

else {

data = NULL;

}

return data;

}

static Uint32 Swap32 (Uint32 v) {

return

((v & 0x000000FF) << 16)

| ((v & 0x0000FF00))

| ((v & 0x00FF0000) >> 16)

| ((v & 0xFF000000));

}

static void xcf_read_property (SDL_RWops * src, xcf_prop * prop) {

prop->id = SDL_ReadBE32 (src);

prop->length = SDL_ReadBE32 (src);

#if DEBUG

printf ("%.8X: %s: %d\n", SDL_RWtell (src), prop->id < 25 ? prop_names [prop->id] : "unknown", prop->length);

#endif

switch (prop->id) {

case PROP_COLORMAP:

prop->data.colormap.num = SDL_ReadBE32 (src);

prop->data.colormap.cmap = (char *) malloc (sizeof (char) * prop->data.colormap.num * 3);

SDL_RWread (src, prop->data.colormap.cmap, prop->data.colormap.num*3, 1);

break;

case PROP_OFFSETS:

prop->data.offset.x = SDL_ReadBE32 (src);

prop->data.offset.y = SDL_ReadBE32 (src);

break;

case PROP_OPACITY:

prop->data.opacity = SDL_ReadBE32 (src);

break;

case PROP_COMPRESSION:

case PROP_COLOR:

SDL_RWread (src, &prop->data, prop->length, 1);

break;

case PROP_VISIBLE:

prop->data.visible = SDL_ReadBE32 (src);

break;

default:

// SDL_RWread (src, &prop->data, prop->length, 1);

SDL_RWseek (src, prop->length, SEEK_CUR);

}

}

static void free_xcf_header (xcf_header * h) {

if (h->cm_num)

free (h->cm_map);

free (h);

}

static xcf_header * read_xcf_header (SDL_RWops * src) {

xcf_header * h;

xcf_prop prop;

h = (xcf_header *) malloc (sizeof (xcf_header));

SDL_RWread (src, h->sign, 14, 1);

h->width = SDL_ReadBE32 (src);

h->height = SDL_ReadBE32 (src);

h->image_type = SDL_ReadBE32 (src);

h->properties = NULL;

h->compr = COMPR_NONE;

h->cm_num = 0;

h->cm_map = NULL;

// Just read, don't save

do {

xcf_read_property (src, &prop);

if (prop.id == PROP_COMPRESSION)

h->compr = prop.data.compression;

else if (prop.id == PROP_COLORMAP) {

// unused var: int i;

h->cm_num = prop.data.colormap.num;

h->cm_map = (unsigned char *) malloc (sizeof (unsigned char) * 3 * h->cm_num);

memcpy (h->cm_map, prop.data.colormap.cmap, 3*sizeof (char)*h->cm_num);

free (prop.data.colormap.cmap);

}

} while (prop.id != PROP_END);

return h;

}

static void free_xcf_layer (xcf_layer * l) {

free (l->name);

free (l);

}

static xcf_layer * read_xcf_layer (SDL_RWops * src) {

xcf_layer * l;

xcf_prop prop;

l = (xcf_layer *) malloc (sizeof (xcf_layer));

l->width = SDL_ReadBE32 (src);

l->height = SDL_ReadBE32 (src);

l->layer_type = SDL_ReadBE32 (src);

l->name = read_string (src);

do {

xcf_read_property (src, &prop);

if (prop.id == PROP_OFFSETS) {

l->offset_x = prop.data.offset.x;

l->offset_y = prop.data.offset.y;

} else if (prop.id == PROP_VISIBLE) {

l->visible = prop.data.visible ? 1 : 0;

}

} while (prop.id != PROP_END);

l->hierarchy_file_offset = SDL_ReadBE32 (src);

l->layer_mask_offset = SDL_ReadBE32 (src);

return l;

}

static void free_xcf_channel (xcf_channel * c) {

free (c->name);

free (c);

}

static xcf_channel * read_xcf_channel (SDL_RWops * src) {

xcf_channel * l;

xcf_prop prop;

l = (xcf_channel *) malloc (sizeof (xcf_channel));

l->width = SDL_ReadBE32 (src);

l->height = SDL_ReadBE32 (src);

l->name = read_string (src);

l->selection = 0;

do {

xcf_read_property (src, &prop);

switch (prop.id) {

case PROP_OPACITY:

l->opacity = prop.data.opacity << 24;

break;

case PROP_COLOR:

l->color = ((Uint32) prop.data.color[0] << 16)

| ((Uint32) prop.data.color[1] << 8)

| ((Uint32) prop.data.color[2]);

break;

case PROP_SELECTION:

l->selection = 1;

break;

case PROP_VISIBLE:

l->visible = prop.data.visible ? 1 : 0;

break;

default:

;

}

} while (prop.id != PROP_END);

l->hierarchy_file_offset = SDL_ReadBE32 (src);

return l;

}

static void free_xcf_hierarchy (xcf_hierarchy * h) {

free (h->level_file_offsets);

free (h);

}

static xcf_hierarchy * read_xcf_hierarchy (SDL_RWops * src) {

xcf_hierarchy * h;

int i;

h = (xcf_hierarchy *) malloc (sizeof (xcf_hierarchy));

h->width = SDL_ReadBE32 (src);

h->height = SDL_ReadBE32 (src);

h->bpp = SDL_ReadBE32 (src);

h->level_file_offsets = NULL;

i = 0;

do {

h->level_file_offsets = (Uint32 *) realloc (h->level_file_offsets, sizeof (Uint32) * (i+1));

h->level_file_offsets [i] = SDL_ReadBE32 (src);

} while (h->level_file_offsets [i++]);

return h;

}

static void free_xcf_level (xcf_level * l) {

free (l->tile_file_offsets);

free (l);

}

static xcf_level * read_xcf_level (SDL_RWops * src) {

xcf_level * l;

int i;

l = (xcf_level *) malloc (sizeof (xcf_level));

l->width = SDL_ReadBE32 (src);

l->height = SDL_ReadBE32 (src);

l->tile_file_offsets = NULL;

i = 0;

do {

l->tile_file_offsets = (Uint32 *) realloc (l->tile_file_offsets, sizeof (Uint32) * (i+1));

l->tile_file_offsets [i] = SDL_ReadBE32 (src);

} while (l->tile_file_offsets [i++]);

return l;

}

static void free_xcf_tile (unsigned char * t) {

free (t);

}

static unsigned char * load_xcf_tile_none (SDL_RWops * src, Uint32 len, int bpp, int x, int y) {

unsigned char * load;

load = (unsigned char *) malloc (len); // expect this is okay

SDL_RWread (src, load, len, 1);

return load;

}

static unsigned char * load_xcf_tile_rle (SDL_RWops * src, Uint32 len, int bpp, int x, int y) {

unsigned char * load, * t, * data, * d;

Uint32 reallen;

int i, size, count, j, length;

unsigned char val;

t = load = (unsigned char *) malloc (len);

reallen = SDL_RWread (src, t, 1, len);

data = (unsigned char *) malloc (x*y*bpp);

for (i = 0; i < bpp; i++) {

d = data + i;

size = x*y;

count = 0;

while (size > 0) {

val = *t++;

length = val;

if (length >= 128) {

length = 255 - (length - 1);

if (length == 128) {

length = (*t << 8) + t[1];

t += 2;

}

count += length;

size -= length;

while (length-- > 0) {

*d = *t++;

d += bpp;

}

}

else {

length += 1;

if (length == 128) {

length = (*t << 8) + t[1];

t += 2;

}

count += length;

size -= length;

val = *t++;

for (j = 0; j < length; j++) {

*d = val;

d += bpp;

}

}

}

}

free (load);

return (data);

}

static Uint32 rgb2grey (Uint32 a) {

Uint8 l;

l = 0.2990 * ((a && 0x00FF0000) >> 16)

+ 0.5870 * ((a && 0x0000FF00) >> 8)

+ 0.1140 * ((a && 0x000000FF));

return (l << 16) | (l << 8) | l;

}

static void create_channel_surface (SDL_Surface * surf, xcf_image_type itype, Uint32 color, Uint32 opacity) {

Uint32 c = 0;

switch (itype) {

case IMAGE_RGB:

case IMAGE_INDEXED:

c = opacity | color;

break;

case IMAGE_GREYSCALE:

c = opacity | rgb2grey (color);

break;

}

SDL_FillRect (surf, NULL, c);

}

static int do_layer_surface (SDL_Surface * surface, SDL_RWops * src, xcf_header * head, xcf_layer * layer, load_tile_type load_tile) {

xcf_hierarchy * hierarchy;

xcf_level * level;

unsigned char * tile;

Uint8 * p8;

Uint16 * p16;

Uint32 * p;

int x, y, tx, ty, ox, oy, i, j;

Uint32 *row;

SDL_RWseek (src, layer->hierarchy_file_offset, SEEK_SET);

hierarchy = read_xcf_hierarchy (src);

level = NULL;

for (i = 0; hierarchy->level_file_offsets [i]; i++) {

SDL_RWseek (src, hierarchy->level_file_offsets [i], SEEK_SET);

level = read_xcf_level (src);

ty = tx = 0;

for (j = 0; level->tile_file_offsets [j]; j++) {

SDL_RWseek (src, level->tile_file_offsets [j], SEEK_SET);

ox = tx+64 > level->width ? level->width % 64 : 64;

oy = ty+64 > level->height ? level->height % 64 : 64;

if (level->tile_file_offsets [j+1]) {

tile = load_tile

(src,

level->tile_file_offsets [j+1] - level->tile_file_offsets [j],

hierarchy->bpp,

ox, oy);

}

else {

tile = load_tile

(src,

ox*oy*6,

hierarchy->bpp,

ox, oy);

}

p8 = tile;

p16 = (Uint16 *) p8;

p = (Uint32 *) p8;

for (y=ty; y < ty+oy; y++) {

row = (Uint32 *)((Uint8 *)surface->pixels + y*surface->pitch + tx*4);

switch (hierarchy->bpp) {

case 4:

for (x=tx; x < tx+ox; x++)

*row++ = Swap32 (*p++);

break;

case 3:

for (x=tx; x < tx+ox; x++) {

*row = 0xFF000000;

*row |= ((Uint32) *(p8++) << 16);

*row |= ((Uint32) *(p8++) << 8);

*row |= ((Uint32) *(p8++) << 0);

row++;

}

break;

case 2: // Indexed/Greyscale + Alpha

switch (head->image_type) {

case IMAGE_INDEXED:

for (x=tx; x < tx+ox; x++) {

*row = ((Uint32) (head->cm_map [*p8*3]) << 16);

*row |= ((Uint32) (head->cm_map [*p8*3+1]) << 8);

*row |= ((Uint32) (head->cm_map [*p8++*3+2]) << 0);

*row |= ((Uint32) *p8++ << 24);;

row++;

}

break;

case IMAGE_GREYSCALE:

for (x=tx; x < tx+ox; x++) {

*row = ((Uint32) *p8 << 16);

*row |= ((Uint32) *p8 << 8);

*row |= ((Uint32) *p8++ << 0);

*row |= ((Uint32) *p8++ << 24);;

row++;

}

break;

default:

fprintf (stderr, "Unknown Gimp image type (%d)\n", head->image_type);

return 1;

}

break;

case 1: // Indexed/Greyscale

switch (head->image_type) {

case IMAGE_INDEXED:

for (x = tx; x < tx+ox; x++) {

*row++ = 0xFF000000

| ((Uint32) (head->cm_map [*p8*3]) << 16)

| ((Uint32) (head->cm_map [*p8*3+1]) << 8)

| ((Uint32) (head->cm_map [*p8*3+2]) << 0);

p8++;

}

break;

case IMAGE_GREYSCALE:

for (x=tx; x < tx+ox; x++) {

*row++ = 0xFF000000

| (((Uint32) (*p8)) << 16)

| (((Uint32) (*p8)) << 8)

| (((Uint32) (*p8)) << 0);

++p8;

}

break;

default:

fprintf (stderr, "Unknown Gimp image type (%d)\n", head->image_type);

return 1;

}

break;

}

}

tx += 64;

if (tx >= level->width) {

tx = 0;

ty += 64;

}

if (ty >= level->height) {

break;

}

free_xcf_tile (tile);

}

free_xcf_level (level);

}

free_xcf_hierarchy (hierarchy);

return 0;

}

SDL_Surface *IMG_LoadXCF_RW(SDL_RWops *src)

{

int start;

const char *error = NULL;

SDL_Surface *surface, *lays;

xcf_header * head;

xcf_layer * layer;

xcf_channel ** channel;

int chnls, i, offsets;

Uint32 offset, fp;

unsigned char * (* load_tile) (SDL_RWops *, Uint32, int, int, int);

if ( !src ) {

/* The error message has been set in SDL_RWFromFile */

return NULL;

}

start = SDL_RWtell(src);

/* Initialize the data we will clean up when we're done */

surface = NULL;

head = read_xcf_header (src);

switch (head->compr) {

case COMPR_NONE:

load_tile = load_xcf_tile_none;

break;

case COMPR_RLE:

load_tile = load_xcf_tile_rle;

break;

default:

fprintf (stderr, "Unsupported Compression.\n");

free_xcf_header (head);

return NULL;

}

/* Create the surface of the appropriate type */

surface = SDL_AllocSurface(SDL_SWSURFACE, head->width, head->height, 32,

0x00FF0000,0x0000FF00,0x000000FF,0xFF000000);

if ( surface == NULL ) {

error = "Out of memory";

goto done;

}

head->layer_file_offsets = NULL;

offsets = 0;

while ((offset = SDL_ReadBE32 (src))) {

head->layer_file_offsets = (Uint32 *) realloc (head->layer_file_offsets, sizeof (Uint32) * (offsets+1));

head->layer_file_offsets [offsets] = offset;

offsets++;

}

fp = SDL_RWtell (src);

lays = SDL_AllocSurface(SDL_SWSURFACE, head->width, head->height, 32,

0x00FF0000,0x0000FF00,0x000000FF,0xFF000000);

if ( lays == NULL ) {

error = "Out of memory";

goto done;

}

// Blit layers backwards, because Gimp saves them highest first

for (i = offsets; i > 0; i--) {

SDL_Rect rs, rd;

SDL_RWseek (src, head->layer_file_offsets [i-1], SEEK_SET);

layer = read_xcf_layer (src);

do_layer_surface (lays, src, head, layer, load_tile);

rs.x = 0;

rs.y = 0;

rs.w = layer->width;

rs.h = layer->height;

rd.x = layer->offset_x;

rd.y = layer->offset_y;

rd.w = layer->width;

rd.h = layer->height;

if (layer->visible)

SDL_BlitSurface (lays, &rs, surface, &rd);

free_xcf_layer (layer);

}

SDL_FreeSurface (lays);

SDL_RWseek (src, fp, SEEK_SET);

// read channels

channel = NULL;

chnls = 0;

while ((offset = SDL_ReadBE32 (src))) {

channel = (xcf_channel **) realloc (channel, sizeof (xcf_channel *) * (chnls+1));

fp = SDL_RWtell (src);

SDL_RWseek (src, offset, SEEK_SET);

channel [chnls++] = (read_xcf_channel (src));

SDL_RWseek (src, fp, SEEK_SET);

}

if (chnls) {

SDL_Surface * chs;

chs = SDL_AllocSurface(SDL_SWSURFACE, head->width, head->height, 32,

0x00FF0000,0x0000FF00,0x000000FF,0xFF000000);

if (chs == NULL) {

error = "Out of memory";

goto done;

}

for (i = 0; i < chnls; i++) {

// printf ("CNLBLT %i\n", i);

if (!channel [i]->selection && channel [i]->visible) {

create_channel_surface (chs, head->image_type, channel [i]->color, channel [i]->opacity);

SDL_BlitSurface (chs, NULL, surface, NULL);

}

free_xcf_channel (channel [i]);

}

SDL_FreeSurface (chs);

}

done:

free_xcf_header (head);

if ( error ) {

SDL_RWseek(src, start, SEEK_SET);

if ( surface ) {

SDL_FreeSurface(surface);

surface = NULL;

}

IMG_SetError(error);

}

return(surface);

}

#else

/* See if an image is contained in a data source */

int IMG_isXCF(SDL_RWops *src)

{

return(0);

}

/* Load a XCF type image from an SDL datasource */

SDL_Surface *IMG_LoadXCF_RW(SDL_RWops *src)

{

return(NULL);

}

#endif /* LOAD_XCF */