short Escape(hdc, SET_SPREAD, sizeof(int),lpSpread, NULL)The SET_SPREAD printer escape sets the amount that nonwhite primitives are expanded for a given device to provide a slight overlap between primitives to compensate for imperfections in the reproduction process.
Spot color separation is the process of separating an image into each distinct color used in the image. The image is reproduced by overprinting each successive color in the image.
When reproducing a spot-separated image, the printing equipment must be calibrated to align each page exactly on each pass. However, differences in temperature, humidity, and so forth between passes often cause images to align imperfectly on subsequent passes. For this reason, lines in spot separations are often widened (spread) slightly to make up for problems in registering subsequent passes through the printer. This process is called trapping. The SET_SPREAD escape implements this process.
hdc
HDC Identifies the device context.
lpSpread
LPINT Points to a short integer that specifies the amount, in pixels, by which all nonwhite primitives are to be expanded.
The return value is the previous spread value.
The default spread is zero.
The current spread applies to all bordered primitives (whether or not the border is visible) and text.