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Designing Your Own Pointers

Mac OS X supports 32-bit RGBA pointers in sizes up to 64 x 64 pixels. If you need a pointer larger than that, you can implement it as a window that tracks with the pointer.

Before you design your own pointer, ask yourself if it is going to add value to the user interface. Recognize that by doing so you are introducing a new, potentially confusing user interface element. If you decide you really need a new pointer, keep the following in mind:

• You need to indicate where the hot spot of the pointer is.
• Your pointers need to be able to work on older hardware that may not provide hardware video acceleration.
• If you create a custom version of a standard pointer, you need to also create new versions of related pointers. For example, if you create a larger arrow pointer you need to also create custom pointers for copy, move, alias, poof, and so forth.

If creating a custom pointer is necessary, both Cocoa and Carbon applications should use NSCursor methods to do so.