/*

IMGLIB: An example image loading library for use with SDL

Copyright (C) 1999 Sam Lantinga

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

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 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

Library General Public License for more details.

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

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

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Sam Lantinga

5635-34 Springhouse Dr.

Pleasanton, CA 94588 (USA)

slouken@devolution.com

*/

/* This is an XPM image file loading framework */

#include <stdio.h>

#include <string.h>

#include <ctype.h>

#include "SDL_image.h"

#ifdef LOAD_XPM

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

int IMG_isXPM(SDL_RWops *src)

{

int is_XPM;

char magic[10];

is_XPM = 0;

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

if ( strncmp(magic, "/* XPM */", 9) == 0 ) {

is_XPM = 1;

}

}

return(is_XPM);

}

static char *SDL_RWgets(char *string, int maxlen, SDL_RWops *src)

{

int i;

for ( i=0; i<(maxlen-1); ++i ) {

if ( SDL_RWread(src, &string[i], 1, 1) <= 0 ) {

/* EOF or error */

if ( i == 0 ) {

/* Hmm, EOF on initial read, return NULL */

string = NULL;

}

break;

}

/* In this case it's okay to use either '\r' or '\n'

as line separators because blank lines are just

ignored by the XPM format.

*/

if ( (string[i] == '\n') || (string[i] == '\n') ) {

break;

}

}

if ( string ) {

string[i] = '\0';

}

return(string);

}

/* Hash table to look up colors from pixel strings */

#define HASH_SIZE 256

struct color_hash {

struct hash_entry {

int keylen;

char *key;

Uint32 color;

struct hash_entry *next;

} *entries[HASH_SIZE];

};

static int hash_key(const char *key, int cpp)

{

int hash;

hash = 0;

while ( cpp-- > 0 ) {

hash += *key++;

}

return(hash%HASH_SIZE);

}

static struct color_hash *create_colorhash(void)

{

struct color_hash *hash;

hash = (struct color_hash *)malloc(sizeof *hash);

if ( hash ) {

memset(hash, 0, (sizeof *hash));

}

return(hash);

}

static int add_colorhash(struct color_hash *hash,

const char *key, int cpp, Uint32 color)

{

int hash_index;

struct hash_entry *prev, *entry;

/* Create the hash entry */

entry = (struct hash_entry *)malloc(sizeof *entry);

if ( ! entry ) {

return(0);

}

entry->keylen = cpp;

entry->key = strdup(key);

if ( ! entry->key ) {

free(entry);

return(0);

}

entry->color = color;

entry->next = NULL;

/* Add it to the hash table */

hash_index = hash_key(key, cpp);

for ( prev = hash->entries[hash_index];

prev && prev->next; prev = prev->next ) {

/* Go to the end of the list */ ;

}

if ( prev ) {

prev->next = entry;

} else {

hash->entries[hash_index] = entry;

}

return(1);

}

static int get_colorhash(struct color_hash *hash,

const char *key, int cpp, Uint32 *color)

{

int hash_index;

struct hash_entry *entry;

hash_index = hash_key(key, cpp);

for ( entry = hash->entries[hash_index]; entry; entry = entry->next ) {

if ( strncmp(key, entry->key, entry->keylen) == 0 ) {

*color = entry->color;

return(1);

}

}

return(0);

}

static void free_colorhash(struct color_hash *hash)

{

int i;

struct hash_entry *entry, *freeable;

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

entry = hash->entries[i];

while ( entry ) {

freeable = entry;

entry = entry->next;

free(freeable->key);

free(freeable);

}

}

free(hash);

}

static int color_to_rgb(const char *colorspec, int *r, int *g, int *b)

{

char rbuf[3];

char gbuf[3];

char bbuf[3];

/* Handle monochrome black and white */

if ( strcasecmp(colorspec, "black") == 0 ) {

*r = 0;

*g = 0;

*b = 0;

return(1);

}

if ( strcasecmp(colorspec, "white") == 0 ) {

*r = 255;

*g = 255;

*b = 255;

return(1);

}

/* Normal hexidecimal color */

switch (strlen(colorspec)) {

case 3:

rbuf[0] = colorspec[0];

rbuf[1] = colorspec[0];

gbuf[0] = colorspec[1];

gbuf[1] = colorspec[1];

bbuf[0] = colorspec[2];

bbuf[1] = colorspec[2];

break;

case 6:

rbuf[0] = colorspec[0];

rbuf[1] = colorspec[1];

gbuf[0] = colorspec[2];

gbuf[1] = colorspec[3];

bbuf[0] = colorspec[4];

bbuf[1] = colorspec[5];

break;

case 12:

rbuf[0] = colorspec[0];

rbuf[1] = colorspec[1];

gbuf[0] = colorspec[4];

gbuf[1] = colorspec[5];

bbuf[0] = colorspec[8];

bbuf[1] = colorspec[9];

break;

default:

return(0);

}

rbuf[2] = '\0';

*r = (int)strtol(rbuf, NULL, 16);

gbuf[2] = '\0';

*g = (int)strtol(gbuf, NULL, 16);

bbuf[2] = '\0';

*b = (int)strtol(bbuf, NULL, 16);

return(1);

}

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

SDL_Surface *IMG_LoadXPM_RW(SDL_RWops *src)

{

SDL_Surface *image;

char line[1024];

char *here, *stop;

int index;

int i, x, y;

int w, h, ncolors, cpp;

int found;

int r, g, b;

Uint32 colorkey;

char *colorkey_string;

int pixels_len;

char *pixels;

int indexed;

Uint8 *dst;

Uint32 pixel;

struct color_hash *colors;

/* Skip to the first string, which describes the image */

image = NULL;

do {

here = SDL_RWgets(line, sizeof(line), src);

if ( ! here ) {

IMG_SetError("Premature end of data");

return(NULL);

}

if ( *here == '"' ) {

++here;

/* Skip to width */

while ( isspace(*here) ) ++here;

w = atoi(here);

while ( ! isspace(*here) ) ++here;

/* Skip to height */

while ( isspace(*here) ) ++here;

h = atoi(here);

while ( ! isspace(*here) ) ++here;

/* Skip to number of colors */

while ( isspace(*here) ) ++here;

ncolors = atoi(here);

while ( ! isspace(*here) ) ++here;

/* Skip to characters per pixel */

while ( isspace(*here) ) ++here;

cpp = atoi(here);

while ( ! isspace(*here) ) ++here;

/* Verify the parameters */

if ( !w || !h || !ncolors || !cpp ) {

IMG_SetError("Invalid format description");

return(NULL);

}

pixels_len = 1+w*cpp+1+1;

pixels = (char *)malloc(pixels_len);

if ( ! pixels ) {

IMG_SetError("Out of memory");

return(NULL);

}

/* Create the new surface */

if ( ncolors <= 256 ) {

indexed = 1;

image = SDL_CreateRGBSurface(SDL_SWSURFACE,

w, h, 8, 0, 0, 0, 0);

} else {

int rmask, gmask, bmask;

indexed = 0;

if ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) {

rmask = 0x000000ff;

gmask = 0x0000ff00;

bmask = 0x00ff0000;

} else {

rmask = 0x00ff0000;

gmask = 0x0000ff00;

bmask = 0x000000ff;

}

image = SDL_CreateRGBSurface(SDL_SWSURFACE,

w, h, 32,

rmask, gmask, bmask, 0);

}

if ( ! image ) {

/* Hmm, some SDL error (out of memory?) */

free(pixels);

return(NULL);

}

}

} while ( ! image );

/* Read the colors */

colors = create_colorhash();

if ( ! colors ) {

SDL_FreeSurface(image);

free(pixels);

IMG_SetError("Out of memory");

return(NULL);

}

colorkey_string = NULL;

for ( index=0; index < ncolors; ++index ) {

here = SDL_RWgets(line, sizeof(line), src);

if ( ! here ) {

SDL_FreeSurface(image);

image = NULL;

IMG_SetError("Premature end of data");

goto done;

}

if ( *here == '"' ) {

const char *key;

++here;

/* Grab the pixel key */

key = here;

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

if ( ! *here++ ) {

/* Parse error */

continue;

}

}

if ( *here ) {

*here++ = '\0';

}

/* Find the color identifier */

found = 0;

while ( *here && ! found ) {

while ( isspace(*here) ) ++here;

if ( (*here != 'c') &&

(*here != 'g') &&

(*here != 'm') ) {

/* Skip color type */

while ( *here && !isspace(*here) )

++here;

/* Skip color name */

while ( isspace(*here) ) ++here;

while ( *here && !isspace(*here) )

++here;

continue;

}

++here;

while ( isspace(*here) ) ++here;

if ( strncasecmp(here, "None", 4) == 0 ) {

colorkey_string = strdup(key);

if ( indexed ) {

colorkey = (Uint32)index;

} else {

colorkey = 0xFFFFFFFF;

}

found = 1;

continue;

}

if ( *here == '#' ) {

++here;

}

while ( isspace(*here) ) ++here;

for ( stop=here; isalnum(*stop); ++stop ) {

/* Skip the pixel color */;

}

*stop++ = '\0';

found = color_to_rgb(here, &r, &g, &b);

if ( found ) {

if ( indexed ) {

SDL_Color *color;

color = &image->format->palette->colors[index];

color->r = (Uint8)r;

color->g = (Uint8)g;

color->b = (Uint8)b;

pixel = index;

} else {

pixel = (r<<16)|(g<<8)|b;

}

add_colorhash(colors, key, cpp, pixel);

}

*here = '\0';

}

if ( ! found ) {

/* Hum, couldn't parse a color.. */;

}

}

}

/* Read the pixels */

for ( y=0; y < h; ) {

here = SDL_RWgets(pixels, pixels_len, src);

if ( ! here ) {

SDL_FreeSurface(image);

image = NULL;

IMG_SetError("Premature end of data");

goto done;

}

if ( *here == '"' ) {

++here;

dst = (Uint8 *)image->pixels + y*image->pitch;

for ( x=0; x<w; ++x ) {

pixel = 0;

if ( colorkey_string &&

(strncmp(here,colorkey_string,cpp)==0) ) {

pixel = colorkey;

} else {

get_colorhash(colors, here,cpp, &pixel);

}

if ( indexed ) {

*dst++ = pixel;

} else {

*((Uint32 *)dst)++ = pixel;

}

for ( i=0; *here && i<cpp; ++i ) {

++here;

}

}

++y;

}

}

if ( colorkey_string ) {

SDL_SetColorKey(image, SDL_SRCCOLORKEY, colorkey);

}

done:

free(pixels);

free_colorhash(colors);

if ( colorkey_string ) {

free(colorkey_string);

}

return(image);

}

#else

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

int IMG_isXPM(SDL_RWops *src)

{

return(0);

}

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

SDL_Surface *IMG_LoadXPM_RW(SDL_RWops *src)

{

return(NULL);

}

#endif /* LOAD_XPM */