Question

From what I’ve read elsewhere, Apple recommends multiple versions of every graphical asset, so quality will be retained between pre-iPhone 4, iPhone 4 (with the retina display), and the iPad. But I’m using a technique that only requires one asset for all three cases.

I make each graphic the size I need for the iPhone 4 and the iPad, say a cat at 500×500 pixels. I name it [e-mail]. When I read it in for the iPhone:

CGRect catFrame = CGRectMake(0.0f, 0.0f, 250.0f, 250.0f);
UIImageView *theCat = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"myCat"]];
theCat.frame = catFrame;
[self.view addSubview:theCat];
[theCat release];

for the iPad, I do exactly the same thing, except for:

CGRect catFrame = CGRectMake(0.0f, 0.0f, 500.0f, 500.0f);

This seems to work fine in all three cases, and greatly reduces the number (and size) of graphic files. Is there anything wrong with this technique?

Answer 1

This question has been a long time in circulation, so I will “answer” it based on my experience with the last couple of apps I’ve worked on.

I see no reason to have a separate image asset for retina display and non-retina display iPhones. The technique I outlined above seems to work just fine.

Probably, one will want a separate asset (“resource file”) for the iPad, mostly for the change in aspect ratio of the screen. In my case (sprites for children’s games) I was able to use many of the iPhone images on the iPad. The “look” was a little different, but I saved a lot of file space.

Whether this works for you will, of course, depend on the unique properties of your project.