Optional Graphics Driver Functions

In the interests of reducing driver size, driver writers usually add only those optional functions that are well-supported in hardware. For example, a driver for hardware that supports Image Color Management (ICM) can implement the DrvIcmXxx functions. The following tables list the functions that a graphics driver can optionally implement.

Display and Printer Driver Functions

Entry Point	Description
DrvAlphaBlend	Provides bit block transfer capabilities with alpha blending.
DrvBitBlt	Executes general bit block transfers to and from surfaces.
DrvCreateDeviceBitmap	Creates and manages a bitmap with a driver-defined format.
DrvDeleteDeviceBitmap	Deletes a device-managed bitmap.
DrvDitherColor	Requests a device to create a brush dithered against a device palette.
DrvFillPath	Paints a closed path for a device-managed surface.
DrvGradientFill	Shades the specified primitives.
DrvIcmCheckBitmapBits	Checks whether the pixels in the specified bitmap lie within the device gamut of the specified transform.
DrvIcmCreateColorTransform	Creates an ICM color transform.
DrvIcmDeleteColorTransform	Deletes the specified ICM color transform.
DrvIcmSetDeviceGammaRamp	Sets the hardware gamma ramp of the specified display device.
DrvLineTo	Draws a single solid integer-only cosmetic line.
DrvPlgBlt	Provides rotate bit block transfer capabilities between combinations of device-managed and GDI-managed surfaces.
DrvRealizeBrush	Realizes a specified brush for a defined surface.
DrvStretchBlt	Allows stretching block transfers among device-managed and GDI-managed surfaces.
DrvStretchBltROP	Performs a stretching bit block transfer using a ROP.
DrvStrokeAndFillPath	Simultaneously fills and strokes a path.
DrvSynchronize	Coordinates drawing operations between GDI and a display driver-supported coprocessor device; for engine-managed surfaces only.
DrvSynchronizeSurface	Coordinates drawing operations between GDI and a display driver-supported coprocessor device; for engine-managed surfaces only. If a driver provides both DrvSynchronize and DrvSynchronizeSurface, GDI will call only DrvSynchronizeSurface.
DrvTransparentBlt	Provides bit block transfer capabilities with transparency.

Functions Used Exclusively by Display Drivers

Entry Point	Description
DrvMovePointer	Moves a pointer to a new position, and redraws it.
DrvSaveScreenBits	Saves or restores a specified rectangle of the screen (display driver only).
DrvSetPointerShape	Removes the pointer from the screen, if the driver has drawn it, and then sets a new pointer shape.

Functions Used Primarily by Printer Drivers

Entry Point	Description
DrvDestroyFont	Notifies driver that a font realization is no longer needed; driver can free allocated data structures.
DrvDrawEscape	Implements draw-type escape functions.
DrvEscape	Queries information from a device not available in a device-independent DDI.
DrvFree	Frees font storage associated with an indicated data structure.

Functions Used Exclusively by Printer Drivers

Entry Point	Description
DrvEndDoc	Sends end-of-document information.
DrvFontManagement	Allows access to printer functionality not directly available through GDI.
DrvGetGlyphMode	Returns type of font information to be stored for a particular font.
DrvNextBand	Realizes the contents of a surface's just-drawn band.
DrvQueryPerBandInfo	Returns banding information for the specified banded printer surface.
DrvSendPage	Sends raw bits from a surface to the printer.
DrvStartBanding	Prepares the driver for banding.
DrvStartDoc	Sends start-of-document control information.
DrvStartPage	Sends start-of-page control information.

Font Driver Function

Entry Point	Description
DrvQueryAdvanceWidths	Supplies character advance widths for a specified set of glyphs.