Inside Macintosh: Apple Game Sprockets Guide /

Chapter 2 - DrawSprocket / DrawSprocket Reference

DrawSprocket Functions / Using Alternate Buffers

DSpContext_SetOverlayAltBuffer

Use the DSpContext_SetOverlayAltBuffer function to designate an alternate buffer to be used as the current overlay buffer for a context.

OSStatus DSpContext_SetOverlayAltBuffer (
DSpContextReference inContext,
DSpAltBufferReference inNewOverlay);

inContext

A reference to the context the overlay is to be used with.

inNewOverlay

A reference to the alternate buffer that holds the overlay.

function result

A result code.

DESCRIPTION

The DSpContext_SetOverlayAltBuffer function makes the alternate buffer specified in the inNewOverlay parameter serve as the current overlay for the context specified in the inContext parameter. You can have multiple overlay buffers--for example, if you have alternate cockpit views--and change between them with this call.

CALLING RESTRICTIONS

Do not call this function during an interrupt.