TQAFlush
A drawing engine must define a method to flush a draw context.
typedef TQAError (*TQAFlush) (const TQADrawContext *drawContext);
drawContext- A draw context.
DESCRIPTION
YourTQAFlushfunction should cause your drawing engine to begin rendering all drawing commands that are queued in a buffer awaiting processing for the draw context specified by thedrawContextparameter. QuickDraw 3D RAVE allows a drawing engine to buffer as many drawing commands as desired. Accordingly, the successful completion of a drawing command (such asQADrawPoint) does not guarantee that the specified object is visible on the screen. An application can callQAFlushto have your drawing engine start processing queued commands. Note, however, thatQAFlushis not a blocking call--that is, the successful completion ofQAFlushdoes not guarantee that all buffered commands have been processed. CallingQAFlushguarantees only that all queued commands will eventually be processed.Typically, applications should occasionally call
QAFlushto update the screen image during a lengthy set of rendering operations in a single-buffered draw context.QAFlushhas no visible effect when called on a double-buffered draw context, but it does initiate rendering to the back buffer.Your
TQAFlushfunction should return a result code (of typeTQAError) indicating whether any errors have occurred since the previous call to yourTQARenderStartfunction. If all rendering commands completed successfully, you should return the valuekQANoErr. If you return any other value, the code that calledQAFlushshould assume that the rendered image is incorrect.
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