Option attributes for the Halftone feature

Important

The modern print platform is Windows' preferred means of communicating with printers. We recommend that you use Microsoft's IPP inbox class driver, along with Print Support Apps (PSA), to customize the print experience in Windows 10 and 11 for printer device development.

For more information, see Modern print platform and the Print support app design guide.

The following table lists the attributes associated with the Halftone feature. For more information about the Halftone feature, see Standard Features.

Attribute name	Attribute parameter	Comments
*HTCallbackID	Positive numeric value passed to the rendering plug-in's IPrintOemUni::HalftonePattern method as its dwCallbackID parameter.	Required if an IPrintOemUni::HalftonePattern method is provided. For more information, see Halftoning with Unidrv.
*HTNumPatterns	Numeric value representing the number of halftone patterns provided. For more information, see Halftoning with Unidrv.	Optional. Can be 1 or 3, where 3 implies separate patterns for red, green, and blue, in that order. If not specified, the default value is 1. Can be used with either *rcHTPatternID or *HTCallbackID.
*HTPatternSize	Pair of numeric values representing the width and height, in pixels, of the pattern specified by *rcHTPatternID.	Required if *rcHTPatternID is specified. The maximum pattern size is PAIR (256, 256). Width and height, multiplied together, must be divisible by 4 for storage as DWORDs
*rcHTPatternID	Resource identifier for an RC_HTPATTERN resource representing halftone pattern data.	Required if a halftone pattern is provided in a resource DLL. For more information, see Halftoning with Unidrv.

For more information about using these attributes, see Halftoning with Unidrv. These attributes are not used with minidriver-supplied halftoning.