SDL_image: We no longer need the UIImage backend, iOS is covered by ImageIO

From 68cecc0e7416c03df1f2786af3c33dc6f78ccecb Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Fri, 13 May 2022 08:52:08 -0700
Subject: [PATCH] We no longer need the UIImage backend, iOS is covered by
 ImageIO

---
 IMG_UIImage.m | 440 --------------------------------------------------
 Makefile.am   |   1 -
 Makefile.in   |   1 -
 3 files changed, 442 deletions(-)
 delete mode 100644 IMG_UIImage.m

diff --git a/IMG_UIImage.m b/IMG_UIImage.m
deleted file mode 100644
index b3028e92..00000000
--- a/IMG_UIImage.m
+++ /dev/null
@@ -1,440 +0,0 @@
-/*
- *  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 <MobileCoreServices/MobileCoreServices.h> // for UTCoreTypes.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 w = CGImageGetWidth(image_ref);
-    size_t h = CGImageGetHeight(image_ref);
-    CGRect rect = {{0, 0}, {w, h}};
-
-    CGImageAlphaInfo alpha = CGImageGetAlphaInfo(image_ref);
-    //size_t bits_per_pixel = CGImageGetBitsPerPixel(image_ref);
-    size_t bits_per_component = 8;
-
-    SDL_Surface* surface;
-    Uint32 Amask;
-    Uint32 Rmask;
-    Uint32 Gmask;
-    Uint32 Bmask;
-
-    CGContextRef bitmap_context;
-    CGBitmapInfo bitmap_info;
-    CGColorSpaceRef color_space = CGColorSpaceCreateDeviceRGB();
-
-    if (alpha == kCGImageAlphaNone ||
-        alpha == kCGImageAlphaNoneSkipFirst ||
-        alpha == kCGImageAlphaNoneSkipLast) {
-        bitmap_info = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Host; /* XRGB */
-        Amask = 0x00000000;
-    } else {
-        /* kCGImageAlphaFirst isn't supported */
-        //bitmap_info = kCGImageAlphaFirst | kCGBitmapByteOrder32Host; /* ARGB */
-        bitmap_info = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host; /* ARGB */
-        Amask = 0xFF000000;
-    }
-
-    Rmask = 0x00FF0000;
-    Gmask = 0x0000FF00;
-    Bmask = 0x000000FF;
-
-    surface = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 32, Rmask, Gmask, Bmask, Amask);
-    if (surface)
-    {
-        // Sets up a context to be drawn to with surface->pixels as the area to be drawn to
-        bitmap_context = CGBitmapContextCreate(
-                                                            surface->pixels,
-                                                            surface->w,
-                                                            surface->h,
-                                                            bits_per_component,
-                                                            surface->pitch,
-                                                            color_space,
-                                                            bitmap_info
-                                                            );
-
-        // Draws the image into the context's image_data
-        CGContextDrawImage(bitmap_context, rect, image_ref);
-
-        CGContextRelease(bitmap_context);
-
-        // FIXME: Reverse the premultiplied alpha
-        if ((bitmap_info & kCGBitmapAlphaInfoMask) == kCGImageAlphaPremultipliedFirst) {
-            int i, j;
-            Uint8 *p = (Uint8 *)surface->pixels;
-            for (i = surface->h * surface->pitch/4; i--; ) {
-#if __LITTLE_ENDIAN__
-                Uint8 A = p[3];
-                if (A) {
-                    for (j = 0; j < 3; ++j) {
-                        p[j] = (p[j] * 255) / A;
-                    }
-                }
-#else
-                Uint8 A = p[0];
-                if (A) {
-                    for (j = 1; j < 4; ++j) {
-                        p[j] = (p[j] * 255) / A;
-                    }
-                }
-#endif /* ENDIAN */
-                p += 4;
-            }
-        }
-    }
-
-    if (color_space)
-    {
-        CGColorSpaceRelease(color_space);
-    }
-
-    return 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;
-
-    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);
-
-    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;
-}
-
-static SDL_Surface* LoadImageFromFile(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];
-    if(ui_image != NULL)
-    {
-        sdl_surface = Create_SDL_Surface_From_CGImage([ui_image CGImage]);
-    }
-
-    [ui_image release];
-    [ns_string 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)
-{
-    SDL_Surface* sdl_surface = NULL;
-
-    sdl_surface = LoadImageFromFile(file);
-    if(NULL == sdl_surface)
-    {
-        // Either the file doesn't exist or ImageIO doesn't understand the format.
-        // For the latter case, fallback to the native SDL_image handlers.
-
-        SDL_RWops *src = SDL_RWFromFile(file, "rb");
-        char *ext = strrchr(file, '.');
-        if(ext) {
-            ext++;
-        }
-        if(!src) {
-            /* The error message has been set in SDL_RWFromFile */
-            return NULL;
-        }
-        sdl_surface = IMG_LoadTyped_RW(src, 1, ext);
-    }
-    return sdl_surface;
-}
-
-
-int IMG_InitJPG()
-{
-    return 0;
-}
-
-void IMG_QuitJPG()
-{
-}
-
-int IMG_InitPNG()
-{
-    return 0;
-}
-
-void IMG_QuitPNG()
-{
-}
-
-int IMG_InitTIF()
-{
-    return 0;
-}
-
-void IMG_QuitTIF()
-{
-}
-
-/* Copied straight from other files so I don't have to alter them. */
-static int IMG_isICOCUR(SDL_RWops *src, int type)
-{
-    int start;
-    int is_ICOCUR;
-
-    /* The Win32 ICO file header (14 bytes) */
-    Uint16 bfReserved;
-    Uint16 bfType;
-    Uint16 bfCount;
-
-    if ( !src )
-        return 0;
-    start = SDL_RWtell(src);
-    is_ICOCUR = 0;
-    bfReserved = SDL_ReadLE16(src);
-    bfType = SDL_ReadLE16(src);
-    bfCount = SDL_ReadLE16(src);
-    if ((bfReserved == 0) && (bfType == type) && (bfCount != 0))
-        is_ICOCUR = 1;
-    SDL_RWseek(src, start, SEEK_SET);
-
-    return (is_ICOCUR);
-}
-
-int IMG_isICO(SDL_RWops *src)
-{
-    return IMG_isICOCUR(src, 1);
-}
-
-int IMG_isCUR(SDL_RWops *src)
-{
-    return IMG_isICOCUR(src, 2);
-}
-
-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_LoadCUR_RW(SDL_RWops *src)
-{
-    /* FIXME: Is this a supported type? */
-    return LoadImageFromRWops(src, CFSTR("com.microsoft.cur"));
-}
-SDL_Surface* IMG_LoadICO_RW(SDL_RWops *src)
-{
-    return LoadImageFromRWops(src, kUTTypeICO);
-}
-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_LoadTGA_RW(SDL_RWops *src)
-{
-    return LoadImageFromRWops(src, CFSTR("com.truevision.tga-image"));
-}
-SDL_Surface* IMG_LoadTIF_RW(SDL_RWops *src)
-{
-    return LoadImageFromRWops(src, kUTTypeTIFF);
-}
-
diff --git a/Makefile.am b/Makefile.am
index 8627fcf0..8c864a2f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -43,7 +43,6 @@ libSDL2_image_la_SOURCES =	\
 EXTRA_DIST = CHANGES.txt LICENSE.txt README.txt README-emscripten.txt \
 	IMG_xxx.c		\
 	IMG_ImageIO.m		\
-	IMG_UIImage.m		\
 	Android.mk		\
 	Makefile.os2		\
 	VisualC			\
diff --git a/Makefile.in b/Makefile.in
index be1a0e5a..69133297 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -479,7 +479,6 @@ libSDL2_image_la_SOURCES = \
 EXTRA_DIST = CHANGES.txt LICENSE.txt README.txt README-emscripten.txt \
 	IMG_xxx.c		\
 	IMG_ImageIO.m		\
-	IMG_UIImage.m		\
 	Android.mk		\
 	Makefile.os2		\
 	VisualC			\