How do you handle iPhone graphics for both high and low DPI settings?

Question

How do you guys create your game graphics for iPhone? Considering you need a retina version and a nomal one?

Do you create a big version of your image, save HD, then resize to smaller version, and save Normal?

Or do you create a vector image with say, fireworks, save HD, then resize, then save Normal?

Answer 1

If you want your images to look good, do not simply scale up/down a raster image. Even with a vector based source, this doesn't always work so well, though the results are usually passable.

The best example of this I can give is this: say you wanted to resize this 48x48 icon into a 24x24 alternative. In 24 pixels, you likely would want to reduce the faux-writing lines from 4 down to 2 or 3. If you just scaled down the image and left it with 4, things would get messy and cramped.

Ultimately, it depends on what the images are being used for. Static images such as buttons and icons you'd want to manually resize, to make sure every pixel is perfect, and it communicates the same concept.
For animated images, the eye doesn't get enough time to fully scrutinize it, so flaws are more acceptable.

Answer 2

For targeting the iPhone, honestly I'd just try to make it look good on the iPhone 4 display. Make sure it is alright on the older devices (specifically fonts), but don't bother going out of your way for them.

At least at this point in time, pre-3GS devices only account for about 5% of the market. Soon I can imagine Apple sunsetting support for any non-retina devices. As long as it's "good enough", it's probably not worth it to put a lot of effort into making your graphics pixel perfect on the older devices.