Binary Raster Operations

Artigo
11/18/2015

A version of this page is also available for

4/8/2010

Binary raster operation codes define how the graphics device interface (GDI) combines the bits from the selected pen with the bits in the destination bitmap.

This topic lists the binary raster-operation codes used by the GetROP2 and SetROP2 functions.

Each raster-operation code represents a Boolean operation in which the values of the pixels in the selected pen and the destination bitmap are combined.

The following table shows the two operands used in these operations.

Operand	Meaning
P	Selected pen
D	Destination bitmap

The following table shows the Boolean operators used by binary raster operations.

Operator	Meaning
a	Bitwise AND
n	Bitwise NOT (inverse)
o	Bitwise OR
x	Bitwise exclusive OR (XOR)

All Boolean operations are presented in reverse Polish notation. For example, the following operation replaces the values of the pixels in the destination bitmap with a combination of the pixel values of the pen and the selected brush:

DPo

Each raster-operation code is a 32-bit integer whose high-order word is a Boolean operation index and whose low-order word is the operation code.

The 16-bit operation index is a zero-extended 8-bit value that represents all possible outcomes resulting from the Boolean operation on two parameters (in this case, the pen and destination values).

For example, the following table shows the operation indexes for the DPo and DPan operations.

P	D	DPo	DPan
0	0	0	1
0	1	1	1
1	0	1	1
1	1	1	0

The following table shows the drawing modes and the Boolean operations that they represent.

Raster operation	Boolean operation
R2_BLACK	0
R2_COPYPEN	P
R2_MASKNOTPEN	DPna
R2_MASKPEN	DPa
R2_MASKPENNOT	PDna
R2_MERGENOTPEN	DPno
R2_MERGEPEN	DPo
R2_MERGEPENNOT	PDno
R2_NOP	D
R2_NOT	Dn
R2_NOTCOPYPEN	Pn
R2_NOTMASKPEN	DPan
R2_NOTMERGEPEN	DPon
R2_NOTXORPEN	DPxn
R2_WHITE	1
R2_XORPEN	DPx

For a monochrome device, GDI maps the value 0 to black and the value 1 to white.

The following table shows the results for an application that attempts to draw with a black pen on a white destination by using the available binary raster operations.

Raster operation	Result
R2_BLACK	Visible black line
R2_COPYPEN	Visible black line
R2_MASKNOTPEN	No visible line
R2_MASKPEN	Visible black line
R2_MASKPENNOT	Visible black line
R2_MERGENOTPEN	No visible line
R2_MERGEPEN	Visible black line
R2_MERGEPENNOT	Visible black line
R2_NOP	No visible line
R2_NOT	Visible black line
R2_NOTCOPYPEN	No visible line
R2_NOTMASKPEN	No visible line
R2_NOTMERGEPEN	Visible black line
R2_NOTXORPEN	Visible black line
R2_WHITE	No visible line
R2_XORPEN	No visible line

For a color device, GDI uses RGB values to represent the colors of the pen and the destination.

An RGB color value is a long integer that contains a red, a green, and a blue color field, each specifying the intensity of the specified color. Intensities range from 0 through 255.

The values are packed in the three low-order bytes of the long integer.

The color of a pen is always a solid color, but the color of the destination may be a mixture of any two or three colors.

The following table shows the results for an application that attempts to draw with a white pen on a blue destination by using the available binary raster operations.

Raster operation	Result
R2_BLACK	Visible black line
R2_COPYPEN	Visible white line
R2_MASKNOTPEN	Visible black line
R2_MASKPEN	Invisible blue line
R2_MASKPENNOT	Visible red/green line
R2_MERGENOTPEN	Invisible blue line
R2_MERGEPEN	Visible white line
R2_MERGEPENNOT	Visible white line
R2_NOP	Invisible blue line
R2_NOT	Visible red/green line
R2_NOTCOPYPEN	Visible black line
R2_NOTMASKPEN	Visible red/green line
R2_NOTMERGEPEN	Visible black line
R2_NOTXORPEN	Invisible blue line
R2_WHITE	Visible white line
R2_XORPEN	Visible red/green line

Compartilhar via

Binary Raster Operations

See Also

Reference

Recursos adicionais