A normal presentation space with segments retained in the segment store can be costly in terms of storage. Therefore, delete any presentation space that you no longer need, using GpiDestroyPS. If, for example, your application is using a series of presentation spaces, each with a different format, the creation and deletion activity also can be costly. The PM provides the following functions that let you reuse or redefine an existing presentation space so you can create a presentation space once and use it any number of times.