Intel Extensible Firmware Interface - Manual (Page 327)

Protocols — Console Support
Version 1.10 12/01/02 10-33
Description
The Blt() function is used to draw the BltBuffer rectangle onto the video screen.
The BltBuffer represents a rectangle of Height by Width pixels that will be drawn on the
graphics screen using the operation specified by BltOperation . The Delta value can be used
to enable the BltOperation to be performed on a sub-rectangle of the BltBuffer .
Table 10-4 describes the BltOperation s that are supported on rectangles. Rectangles have
coordinates (left, upper) (right, bottom):
Table 10-4. Blt Operation Table
Blt Operation Operation
EfiUgaVideoFill Write data from the BltBuffer pixel ( SourceX ,
SourceY ) directly to every pixel of the video display
rectangle ( DestinationX , DestinationY )
( DestinationX + Width , DestinationY + Height ).
Only one pixel will be used from the BltBuffer . Delta
is NOT used.
EfiUgaVideoToBltBuffer Read data from the video display rectangle ( SourceX ,
SourceY ) ( SourceX + Width , SourceY + Height ) and
place it in the BltBuffer rectangle ( DestinationX ,
DestinationY ) ( DestinationX + Width ,
DestinationY + Height ). If DestinationX or
DestinationY is not zero then Delta must be set to
the length in bytes of a row in the BltBuffer .
EfiUgaBltBufferToVideo Write data from the BltBuffer rectangle ( SourceX ,
SourceY ) ( SourceX + Width , SourceY + Height )
directly to the video display rectangle ( DestinationX ,
DestinationY ) ( DestinationX + Width ,
DestinationY + Height ). If SourceX or SourceY is
not zero then Delta must be set to the length in bytes
of a row in the BltBuffer .
EfiUgaVideoToVideo Copy from the video display rectangle ( SourceX ,
SourceY ) ( SourceX + Width , SourceY + Height ) to
the video display rectangle ( X , Y ) ( X + Width , Y +
Height ). The BltBuffer and Delta are not used in
this mode. There is no limitation on the overlapping of
the source and destination rectangles.
Status Codes Returned
EFI_SUCCESS BltBuffer was drawn to the graphics screen.
EFI_INVALID_PARAMETER BltOperation is not valid.
EFI_DEVICE_ERROR The device had an error and could not complete the request.