short Escape(hDC, SET_SCREEN_ANGLE, sizeof(int),lpAngle, NULL)
This escape sets the current screen angle to the desired angle and enables an application to simulate the tilting of a photographic mask in producing a color separation for a particular primary.
| Parameter | Type/Description |
| hDC | HDC Identifies the device context. | |
| lpAngle | LPINT Points to a short-integer value specifying the desired screen angle in tenths of a degree. The angle is measured counterclockwise. |
The return value is the previous screen angle.
Four-color process separation is the process of separating the colors comprising an image into four component primaries: cyan, magenta, yellow, and black. The image is then reproduced by overprinting each primary.
In traditional four-color process printing, half-tone images for each of the four primaries are photographed against a mask tilted to a particular angle. Tilting the mask in this manner minimizes unwanted moire patterns caused by overprinting two or more colors.
The device driver defines the default screen angle.