Chapter 2 - Where to Begin

Part 1 - formats

ThemePark allows you to create themes in one of 4 different formats: guiKit, DLTA, XScheme, or Resource-Based DLTA. The vast majority of you will want to create guiKits, but here's the breakdown.

guiKit aka "For ShapeShifter"
This format was created by Unsanity to be used by ShapeShifter (by far the best theme changing program currently available). guiKit has a number of advantages over the other formats, and is the standard format for themes. It has excellent compression, it lets you to change text colors, it can automatically install "app skins" which apply custom theme graphics to applications (such as iTunes) that have a number of exclusive graphics that are not modified by global system changes. In fact, the guiKit format let's you change all kinds of things that no other format can, and all without actually modifying system elements through the magic of ShapeShifter. The major disadvantage of the guiKit format is that ShapeShifter costs $20. While guiKit elements can be extracted through Unsanity's free guiKitty, there is no way to apply all of them without ShapeShifter.

DLTA
DLTA is the only real alternative to guiKit. It can be applied with a number of applications, including ThemeChanger. This free and open source application was once the standard in theming, but was unseated almost immediately once ShapeShifter was released. Nevertheless, a fair number of people do not use ShapeShifter (for reasons ranging from cost to debatable stability), so releasing themes in DLTA format as an alternative to guiKit can only help more people enjoy your theme. It should be noted that a guiKit in ThemePark can be exported as a DLTA, not requiring any extra work on your part, but a number of the special features only available in guiKit will not function quite as expected (how much so depending on how much you rely on guiKit-exclusive features).

Resource-Based DLTA
Newer than the DLTA format and outputs a smaller file. While a traditional DLTA includes all resources, a Resource-Based DLTA exports only the resources you've modified. In other words, if you modify the Finder back button but not the forward button, a Resource-Based DLTA will only export the back button. A traditional DLTA would export both buttons.

Generally speaking, you'll have better luck applying a Resource-Based DLTA to an unintended OS version than you would with a traditional DLTA because it isn't trying to replace every resource, many of which might have been changed from one version of the OS to the next. I still don't recommend either DLTA format, but if you're really against the guiKit, ShapeShifter, and APE triumverate it's the way to go.

XScheme
XScheme is Carpe Stellarem's format, designed for their theme changer Duality. ThemePark does not support the newer versions of XScheme, so this format can safely be ignored.