SetROP2 function (wingdi.h)

Article
10/13/2021

The SetROP2 function sets the current foreground mix mode. GDI uses the foreground mix mode to combine pens and interiors of filled objects with the colors already on the screen. The foreground mix mode defines how colors from the brush or pen and the colors in the existing image are to be combined.

Syntax

int SetROP2(
  [in] HDC hdc,
  [in] int rop2
);

Parameters

[in] hdc

A handle to the device context.

[in] rop2

The mix mode. This parameter can be one of the following values.

Mix mode	Meaning
R2_BLACK	Pixel is always 0.
R2_COPYPEN	Pixel is the pen color.
R2_MASKNOTPEN	Pixel is a combination of the colors common to both the screen and the inverse of the pen.
R2_MASKPEN	Pixel is a combination of the colors common to both the pen and the screen.
R2_MASKPENNOT	Pixel is a combination of the colors common to both the pen and the inverse of the screen.
R2_MERGENOTPEN	Pixel is a combination of the screen color and the inverse of the pen color.
R2_MERGEPEN	Pixel is a combination of the pen color and the screen color.
R2_MERGEPENNOT	Pixel is a combination of the pen color and the inverse of the screen color.
R2_NOP	Pixel remains unchanged.
R2_NOT	Pixel is the inverse of the screen color.
R2_NOTCOPYPEN	Pixel is the inverse of the pen color.
R2_NOTMASKPEN	Pixel is the inverse of the R2_MASKPEN color.
R2_NOTMERGEPEN	Pixel is the inverse of the R2_MERGEPEN color.
R2_NOTXORPEN	Pixel is the inverse of the R2_XORPEN color.
R2_WHITE	Pixel is always 1.
R2_XORPEN	Pixel is a combination of the colors in the pen and in the screen, but not in both.

Return value

If the function succeeds, the return value specifies the previous mix mode.

If the function fails, the return value is zero.

Remarks

Mix modes define how GDI combines source and destination colors when drawing with the current pen. The mix modes are binary raster operation codes, representing all possible Boolean functions of two variables, using the binary operations AND, OR, and XOR (exclusive OR), and the unary operation NOT. The mix mode is for raster devices only; it is not available for vector devices.

Examples

For an example, see Using Rectangles.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	wingdi.h (include Windows.h)
Library	Gdi32.lib
DLL	Gdi32.dll