我注意到了將圖像放入核心圖形的兩種方法的示例。一個比另一個簡單得多。那麼第二個更復雜的方法有什麼優勢呢?速度更快嗎?將圖像放入圖形上下文的兩種方式 - 哪種更好?
例如1個
UIImage *myImage = [UIImage imageNamed:@"picture.png"];
CGRect imageRect = CGRectMake(70, 330, 40, 40);
[myImage drawInRect:imageRect];
[myImage release];
例如2
// Load image from application bundle
NSString* imageFileName = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"picture.png"];
CGDataProviderRef provider = CGDataProviderCreateWithFilename([imageFileName UTF8String]);
CGImageRef image = CGImageCreateWithPNGDataProvider(provider, NULL, true, kCGRenderingIntentDefault);
CGDataProviderRelease(provider);
// Draw image
CGContextTranslateCTM(context, 70, 370);
CGContextScaleCTM(context, 1.0, -1.0);
CGContextDrawImage(context, CGRectMake(0, 0, 40, 40), image);
CGImageRelease(image);