/*

* IMG_ImageIO.c

* SDL_image

*

* Created by Eric Wing on 1/2/09.

* Copyright 2009 __MyCompanyName__. All rights reserved.

*

*/

#include "SDL_image.h"

#import <UIKit/UIKit.h>

#import <Foundation/Foundation.h>

// Once we have our image, we need to get it into an SDL_Surface

// (Copied straight from the ImageIO backend.)

static SDL_Surface* Create_SDL_Surface_From_CGImage(CGImageRef image_ref)

{

/* This code is adapted from Apple's Documentation found here:

* http://developer.apple.com/documentation/GraphicsImaging/Conceptual/OpenGL-MacProgGuide/index.html

* Listing 9-4††Using a Quartz image as a texture source.

* Unfortunately, this guide doesn't show what to do about

* non-RGBA image formats so I'm making the rest up.

* All this code should be scrutinized.

*/

size_t the_width = CGImageGetWidth(image_ref);

size_t the_height = CGImageGetHeight(image_ref);

CGRect the_rect = {{0, 0}, {the_width, the_height}};

size_t bits_per_pixel = CGImageGetBitsPerPixel(image_ref);

size_t bytes_per_row = CGImageGetBytesPerRow(image_ref);

// size_t bits_per_component = CGImageGetBitsPerComponent(image_ref);

size_t bits_per_component = 8;

// CGImageAlphaInfo alpha_info = CGImageGetAlphaInfo(image_ref);

SDL_Surface* sdl_surface = NULL;

Uint32 Rmask;

Uint32 Gmask;

Uint32 Bmask;

Uint32 Amask;

CGContextRef bitmap_context = NULL;

CGColorSpaceRef color_space = NULL;

CGBitmapInfo bitmap_info = CGImageGetBitmapInfo(image_ref);

switch(bits_per_pixel)

{

case 8:

{

bytes_per_row = the_width*4;

// color_space = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);

color_space = CGColorSpaceCreateDeviceRGB();

// bitmap_info = kCGImageAlphaPremultipliedFirst;

#if __BIG_ENDIAN__

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big; /* XRGB Big Endian */

#else

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little; /* XRGB Little Endian */

#endif

Rmask = 0x00FF0000;

Gmask = 0x0000FF00;

Bmask = 0x000000FF;

Amask = 0x00000000;

sdl_surface = SDL_CreateRGBSurface(SDL_SWSURFACE,

the_width, the_height, 32, Rmask, Gmask, Bmask, Amask);

break;

}

case 15:

case 16:

{

bytes_per_row = the_width*4;

color_space = CGColorSpaceCreateDeviceRGB();

#if __BIG_ENDIAN__

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big; /* XRGB Big Endian */

#else

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little; /* XRGB Little Endian */

#endif

Rmask = 0x00FF0000;

Gmask = 0x0000FF00;

Bmask = 0x000000FF;

Amask = 0x00000000;

sdl_surface = SDL_CreateRGBSurface(SDL_SWSURFACE,

the_width, the_height, 32, Rmask, Gmask, Bmask, Amask);

break;

}

case 24:

{

bytes_per_row = the_width*4;

// color_space = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);

color_space = CGColorSpaceCreateDeviceRGB();

// bitmap_info = kCGImageAlphaNone;

#if __BIG_ENDIAN__

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big; /* XRGB Big Endian */

#else

bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little; /* XRGB Little Endian */

#endif

Rmask = 0x00FF0000;

Gmask = 0x0000FF00;

Bmask = 0x000000FF;

Amask = 0x00000000;

sdl_surface = SDL_CreateRGBSurface(SDL_SWSURFACE,

the_width, the_height, 32, Rmask, Gmask, Bmask, Amask);

break;

}

case 32:

{

bytes_per_row = the_width*4;

// color_space = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);

color_space = CGColorSpaceCreateDeviceRGB();

// bitmap_info = kCGImageAlphaPremultipliedFirst;

#if __BIG_ENDIAN__

bitmap_info = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Big; /* XRGB Big Endian */

#else

bitmap_info = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Little; /* XRGB Little Endian */

#endif

Amask = 0xFF000000;

Rmask = 0x00FF0000;

Gmask = 0x0000FF00;

Bmask = 0x000000FF;

sdl_surface = SDL_CreateRGBSurface(SDL_SWSURFACE,

the_width, the_height, 32, Rmask, Gmask, Bmask, Amask);

break;

}

default:

{

sdl_surface = NULL;

break;

}

}

if(NULL == sdl_surface)

{

if(color_space != NULL)

{

CGColorSpaceRelease(color_space);

}

return NULL;

}

// Sets up a context to be drawn to with sdl_surface->pixels as the area to be drawn to

bitmap_context = CGBitmapContextCreate(

sdl_surface->pixels,

the_width,

the_height,

bits_per_component,

bytes_per_row,

color_space,

bitmap_info

);

// Draws the image into the context's image_data

CGContextDrawImage(bitmap_context, the_rect, image_ref);

CGContextRelease(bitmap_context);

CGColorSpaceRelease(color_space);

return sdl_surface;

}

static SDL_Surface* LoadImageFromRWops(SDL_RWops* rw_ops, CFStringRef uti_string_hint)

{

NSAutoreleasePool* autorelease_pool = [[NSAutoreleasePool alloc] init];

SDL_Surface* sdl_surface;

UIImage* ui_image;

CGImageRef image_ref = NULL;

int bytes_read = 0;

// I don't know what a good size is.

// Max recommended texture size is 1024x1024 on iPhone so maybe base it on that?

const int block_size = 1024*4;

char temp_buffer[block_size];

NSMutableData* ns_data = [[NSMutableData alloc] initWithCapacity:1024*1024*4];

do

{

bytes_read = SDL_RWread(rw_ops, temp_buffer, 1, block_size);

[ns_data appendBytes:temp_buffer length:bytes_read];

} while(bytes_read > 0);

if(NULL == image_ref)

{

return NULL;

}

ui_image = [[UIImage alloc] initWithData:ns_data];

sdl_surface = Create_SDL_Surface_From_CGImage([ui_image CGImage]);

[ui_image release];

[ns_data release];

[autorelease_pool drain];

return sdl_surface;

}

/* Since UIImage doesn't really support streams well, we should optimize for the file case. */

SDL_Surface *IMG_Load(const char *file)

{

NSAutoreleasePool* autorelease_pool = [[NSAutoreleasePool alloc] init];

SDL_Surface* sdl_surface = NULL;

UIImage* ui_image;

NSString* ns_string;

ns_string = [[NSString alloc] initWithUTF8String:file];

ui_image = [[UIImage alloc] initWithContentsOfFile:ns_string];

sdl_surface = Create_SDL_Surface_From_CGImage([ui_image CGImage]);

[ui_image release];

[ns_string release];

[autorelease_pool drain];

return sdl_surface;

}

/* Copied straight from other files so I don't have to alter them. */

int IMG_isBMP(SDL_RWops *src)

{

int start;

int is_BMP;

char magic[2];

if ( !src )

return 0;

start = SDL_RWtell(src);

is_BMP = 0;

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

if ( strncmp(magic, "BM", 2) == 0 ) {

is_BMP = 1;

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_BMP);

}

int IMG_isGIF(SDL_RWops *src)

{

int start;

int is_GIF;

char magic[6];

if ( !src )

return 0;

start = SDL_RWtell(src);

is_GIF = 0;

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

if ( (strncmp(magic, "GIF", 3) == 0) &&

((memcmp(magic + 3, "87a", 3) == 0) ||

(memcmp(magic + 3, "89a", 3) == 0)) ) {

is_GIF = 1;

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_GIF);

}

int IMG_isJPG(SDL_RWops *src)

{

int start;

int is_JPG;

int in_scan;

Uint8 magic[4];

/* This detection code is by Steaphan Greene <stea@cs.binghamton.edu> */

/* Blame me, not Sam, if this doesn't work right. */

/* And don't forget to report the problem to the the sdl list too! */

if ( !src )

return 0;

start = SDL_RWtell(src);

is_JPG = 0;

in_scan = 0;

if ( SDL_RWread(src, magic, 2, 1) ) {

if ( (magic[0] == 0xFF) && (magic[1] == 0xD8) ) {

is_JPG = 1;

while (is_JPG == 1) {

if(SDL_RWread(src, magic, 1, 2) != 2) {

is_JPG = 0;

} else if( (magic[0] != 0xFF) && (in_scan == 0) ) {

is_JPG = 0;

} else if( (magic[0] != 0xFF) || (magic[1] == 0xFF) ) {

/* Extra padding in JPEG (legal) */

/* or this is data and we are scanning */

SDL_RWseek(src, -1, SEEK_CUR);

} else if(magic[1] == 0xD9) {

/* Got to end of good JPEG */

break;

} else if( (in_scan == 1) && (magic[1] == 0x00) ) {

/* This is an encoded 0xFF within the data */

} else if( (magic[1] >= 0xD0) && (magic[1] < 0xD9) ) {

/* These have nothing else */

} else if(SDL_RWread(src, magic+2, 1, 2) != 2) {

is_JPG = 0;

} else {

/* Yes, it's big-endian */

Uint32 start;

Uint32 size;

Uint32 end;

start = SDL_RWtell(src);

size = (magic[2] << 8) + magic[3];

end = SDL_RWseek(src, size-2, SEEK_CUR);

if ( end != start + size - 2 ) is_JPG = 0;

if ( magic[1] == 0xDA ) {

/* Now comes the actual JPEG meat */

#ifdef FAST_IS_JPEG

/* Ok, I'm convinced. It is a JPEG. */

break;

#else

/* I'm not convinced. Prove it! */

in_scan = 1;

#endif

}

}

}

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_JPG);

}

int IMG_isPNG(SDL_RWops *src)

{

int start;

int is_PNG;

Uint8 magic[4];

if ( !src )

return 0;

start = SDL_RWtell(src);

is_PNG = 0;

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

if ( magic[0] == 0x89 &&

magic[1] == 'P' &&

magic[2] == 'N' &&

magic[3] == 'G' ) {

is_PNG = 1;

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_PNG);

}

int IMG_isTIF(SDL_RWops* src)

{

int start;

int is_TIF;

Uint8 magic[4];

if ( !src )

return 0;

start = SDL_RWtell(src);

is_TIF = 0;

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

if ( (magic[0] == 'I' &&

magic[1] == 'I' &&

magic[2] == 0x2a &&

magic[3] == 0x00) ||

(magic[0] == 'M' &&

magic[1] == 'M' &&

magic[2] == 0x00 &&

magic[3] == 0x2a) ) {

is_TIF = 1;

}

}

SDL_RWseek(src, start, SEEK_SET);

return(is_TIF);

}

SDL_Surface* IMG_LoadBMP_RW(SDL_RWops *src)

{

return LoadImageFromRWops(src, kUTTypeBMP);

}

SDL_Surface* IMG_LoadGIF_RW(SDL_RWops *src)

{

return LoadImageFromRWops(src, kUTTypeGIF);

}

SDL_Surface* IMG_LoadJPG_RW(SDL_RWops *src)

{

return LoadImageFromRWops(src, kUTTypeJPEG);

}

SDL_Surface* IMG_LoadPNG_RW(SDL_RWops *src)

{

return LoadImageFromRWops(src, kUTTypePNG);

}

SDL_Surface* IMG_LoadTIF_RW(SDL_RWops *src)

{

return LoadImageFromRWops(src, kUTTypeTIFF);

}