MMProgRef - DIVE Functions

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Multimedia Programming Reference

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Direct interface video extensions (DIVE) provide optimized blitting performance for motion video subsystems and applications that perform rapid screen updates in the OS/2 PM and full-screen environments. Using the DIVE interface, applications can either write directly to video memory or use the DIVE blitter. The DIVE blitter will take advantage of acceleration hardware when present and applicable to the function being performed.

The following table describes the DIVE functions.

Function	Description
DiveAcquireFrameBuffer	Allows the frame buffer to be serialized.
DiveAllocImageBuffer	Allocates a buffer to contain an image.
DiveBeginImageBufferAccess	Begins access to the image buffer.
DiveBlitImage	Transfers an image from the source to its destination.
DiveBlitImageLines	Transfers only the changed lines of an image from the source to its destination.
DiveCalcFrameBufferAddress	Calculates linear frame buffer address.
DiveClose	Closes instance.
DiveDeacquireFrameBuffer	Releases exclusive access to the frame buffer.
DiveEndImageBufferAccess	Ends access to the image buffer.
DiveFreeImageBuffer	Deallocates an image buffer allocated by DiveAllocImageBuffer.
DiveOpen	Opens a display engine instance.
DiveQueryCaps	Queries display capabilities.
DiveSetDestinationPalette	Sets palette associated with the destination of DiveBlitImage.
DiveSetupBlitter	Sets up blitter operations.
DiveSetSourcePalette	Sets the palette associated with source data.
DiveSetTransparentBlitMode	Enables transparent blitting using a chroma-key color or chroma-keying on a color space range.
DiveSwitchBank	Selects VRAM bank for bank-switched displays.