Binary Raster Operations
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 |
See Also
Raster Operation Codes | Ternary Raster Operations | GetROP2 | SetROP2
Last updated on Wednesday, April 13, 2005
© 2005 Microsoft Corporation. All rights reserved.