halftone-algorithms.md

title	description	keywords	ms.date
Halftone Algorithms	Halftone Algorithms	HP-GL/2 monochrome WDK Unidrv , halftone algorithms PCL-5e WDK Unidrv , halftone algorithms halftoning WDK Unidrv	01/27/2023

Halftone Algorithms

[!includePrint Support Apps]

Some printer vendors prefer to use different halftone algorithms while printing different kinds of objects, such as text, vector objects, and bitmaps. The three examples that follow show what should be added to the GPD to print each of these types of objects.

The first example shows how to incorporate halftone rendering while printing text.

*Ifdef: WINNT_51
*Feature: TEXTHALFTONE
{
  *rcNameID: =TEXTHALFTONE_DISPLAY
  *DefaultOption: DETAIL
  *Option: DETAIL
   {
     *rcNameID: =DETAIL_HT_DISPLAY
     *Command: CmdSetTextHTAlgo { *Cmd : "<1B>*t0J" }
   }
  *Option: SMOOTH
   {
     *rcNameID: =SMOOTH_HT_DISPLAY
     *Name: "Smooth"
     *Command: CmdSetTextHTAlgo { *Cmd : "<1B>*t15J" }
   }
  *Option: BASIC
   {
     *rcNameID: =BASIC_HT_DISPLAY
     *Command: CmdSetTextHTAlgo { *Cmd : "<1B>*t18J" }
   }
}
*Endif:

The second example includes commands for halftone rendering while printing vector graphics.

*Ifdef:  WINNT_51
*Feature: GRAPHICSHALFTONE
{
  *rcNameID: =GRAPHICSHALFTONE_DISPLAY
  *DefaultOption: SMOOTH
  *Option: DETAIL
   {
     *rcNameID: =DETAIL_HT_DISPLAY
     *Command: CmdSetGraphicsHTAlgo { *Cmd : "<1B>*t15J" }
   }
  *Option: SMOOTH
   {
     *rcNameID: =SMOOTH_HT_DISPLAY
     *Command: CmdSetGraphicsHTAlgo { *Cmd : "<1B>*t18J" }
   }
  *Option: BASIC
   {
     *rcNameID: =BASIC_HT_DISPLAY
     *Command: CmdSetGraphicsHTAlgo { *Cmd : "<1B>*t18J" }
   }
}
*Endif:

The third example includes commands for halftone rendering while printing bitmaps.

*Ifdef: WINNT_51
*Feature: PHOTOHALFTONE
{
  *rcNameID: =PHOTOHALFTONE_DISPLAY
  *DefaultOption: SMOOTH
  *Option: DETAIL
   {
     *rcNameID: =DETAIL_HT_DISPLAY
     *Command: CmdSetPhotoHTAlgo { *Cmd : "<1B>*t15J" }
   }
  *Option: SMOOTH
   {
     *rcNameID: =SMOOTH_HT_DISPLAY
     *Command: CmdSetPhotoHTAlgo { *Cmd : "<1B>*t7J" }
   }
  *Option: BASIC
   {
     *rcNameID: =BASIC_HT_DISPLAY
     *Command: CmdSetPhotoHTAlgo { *Cmd : "<1B>*t3J" }
   }
}
*Endif: