BitBlt
The BitBlt
function performs a bit-block transfer of the color data corresponding to a
rectangle of pixels from the specified source device context into a destination
device context.
BOOL BitBlt(
|
HDC hdcDest, |
// handle to
destination device context |
|
int nXDest, |
// x-coordinate of
destination rectangle s upper-left corner |
|
int nYDest, |
// y-coordinate of
destination rectangle s upper-left corner |
|
int nWidth, |
// width of
destination rectangle |
|
int nHeight, |
// height of
destination rectangle |
|
HDC hdcSrc, |
// handle to source
device context |
|
int nXSrc, |
// x-coordinate of
source rectangle s upper-left corner |
|
int nYSrc, |
// y-coordinate of
source rectangle s upper-left corner |
|
DWORD dwRop |
// raster operation
code |
|
); |
|
Parameters
hdcDest
Identifies
the destination device context.
nXDest
Specifies the
logical x-coordinate of the upper-left corner of the destination rectangle.
nYDest
Specifies the
logical y-coordinate of the upper-left corner of the destination rectangle.
nWidth
Specifies the
logical width of the source and destination rectangles.
nHeight
Specifies the
logical height of the source and the destination rectangles.
hdcSrc
Identifies
the source device context.
nXSrc
Specifies the
logical x-coordinate of the upper-left corner of the source rectangle.
nYSrc
Specifies the
logical y-coordinate of the upper-left corner of the source rectangle.
dwRop
Specifies a
raster-operation code. These codes define how the color data for the source
rectangle is to be combined with the color data for the destination rectangle
to achieve the final color.
The following
list shows some common raster operation codes:
|
Value |
Description |
|
BLACKNESS |
Fills the
destination rectangle using the color associated with index 0 in the physical
palette. (This color is black for the default physical palette.) |
|
DSTINVERT |
Inverts the
destination rectangle. |
|
MERGECOPY |
Merges the
colors of the source rectangle with the specified pattern by using the
Boolean AND operator. |
|
MERGEPAINT |
Merges the
colors of the inverted source rectangle with the colors of the destination
rectangle by using the Boolean OR operator. |
|
NOTSRCCOPY |
Copies the
inverted source rectangle to the destination. |
|
NOTSRCERASE |
Combines
the colors of the source and destination rectangles by using the Boolean OR
operator and then inverts the resultant color. |
|
PATCOPY |
Copies the
specified pattern into the destination bitmap. |
|
PATINVERT |
Combines
the colors of the specified pattern with the colors of the destination
rectangle by using the Boolean XOR operator. |
|
PATPAINT |
Combines
the colors of the pattern with the colors of the inverted source rectangle by
using the Boolean OR operator. The result of this operation is combined with
the colors of the destination rectangle by using the Boolean OR operator. |
|
SRCAND |
Combines
the colors of the source and destination rectangles by using the Boolean AND
operator. |
|
SRCCOPY |
Copies the
source rectangle directly to the destination rectangle. |
|
SRCERASE |
Combines
the inverted colors of the destination rectangle with the colors of the
source rectangle by using the Boolean AND operator. |
|
SRCINVERT |
Combines the
colors of the source and destination rectangles by using the Boolean XOR
operator. |
|
SRCPAINT |
Combines
the colors of the source and destination rectangles by using the Boolean OR
operator. |
|
WHITENESS |
Fills the
destination rectangle using the color associated with index 1 in the physical
palette. (This color is white for the default physical palette.) |
Return Values
If the
function succeeds, the return value is nonzero.
If the
function fails, the return value is zero. To get extended error information, call
GetLastError.
Remarks
If a rotation
or shear transformation is in effect in the source device context, BitBlt
returns an error. If other transformations exist in the source device context
(and a matching transformation is not in effect in the destination
device context), the rectangle in the destination device context is stretched,
compressed, or rotated as necessary.
If the color
formats of the source and destination device contexts do not match, the BitBlt
function converts the source color format to match the destination format.
When an
enhanced metafile is being recorded, an error occurs if the source device
context identifies an enhanced-metafile device context.
Not all
devices support the BitBlt function. For more information, see the RC_BITBLT
raster capability entry in GetDeviceCaps.
BitBlt returns an error if the source and destination device
contexts represent different devices.
See Also