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OneSadCookie

Luminary

Posts: 5,131
Joined: 2002.04

Post: #16

Jan 29, 2010 — 06:25 PM

ImageIO was introduced with 10.4.

NelsonMandella

Member

Posts: 194
Joined: 2009.02

Post: #17

Jan 29, 2010 — 07:34 PM

AnotherJake Wrote:For something that works on both iPhone and Mac to load a PNG, you can do something like this (I just kind of threw it together real quick, so it's pseudocode-ish, but you should be able to figure it out from here):

Code:

NSURL *url = [NSURL fileURLWithPath:myPath]; if (url == NULL) { NSLog(@"%s ERROR: Unable to create URL", __FUNCTION__); return; } CGDataProviderRef source = CGDataProviderCreateWithURL((CFURLRef)url); if (source == NULL) { printf("%s ERROR: Unable to create data provider from file URL", __FUNCTION__); return; } CGImageRef image = CGImageCreateWithPNGDataProvider(source, nil, NO, kCGRenderingIntentDefault); if(image == NULL) { NSLog(@"%s ERROR: unable to load: %@.%@", __FUNCTION__, texture[texID].file, extension); CGDataProviderRelease(source); return; } CGSize imageSize = CGSizeMake(CGImageGetWidth(image), CGImageGetHeight(image)); NSUInteger width = imageSize.width; NSUInteger height = imageSize.height; CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); void *pixels = calloc(width * height * 4, 1); CGContextRef context = CGBitmapContextCreate(pixels, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big); CGColorSpaceRelease(colorSpace); CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
I don't know if this works on 10.4 though. I don't target 10.4 anymore since I've seen too much anecdotal evidence that few use it anymore.

Thanks a lot. The code works except that it's drawing everything rotated 180 degrees, upside down and backwards, is there some way to flip the context or image?

AnotherJake

Moderator

Posts: 3,554
Joined: 2003.06

Post: #18

Jan 29, 2010 — 08:24 PM

NelsonMandella Wrote:Thanks a lot. The code works except that it's drawing everything rotated 180 degrees, upside down and backwards, is there some way to flip the context or image?

Picky!

The flipY stuff is the only mod you should need:

Code:

colorSpace = CGColorSpaceCreateDeviceRGB();

pixels = calloc(width * height * 4, 1);

context = CGBitmapContextCreate(pixels, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);

CGColorSpaceRelease(colorSpace);

if (flipY)

{

    CGContextTranslateCTM(context, 0, (float)(height));

    CGContextScaleCTM(context, 1.0, -1.0);

}

CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);