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GPR_$SET_DRAW_VALUE               GPR Calls                GPR_$SET_DRAW_VALUE


NAME
     gpr_$set_draw_value - specifies the color/intensity value to use to draw
     lines.

FORMAT
     gpr_$set_draw_value (color, status)

DESCRIPTION
     This routine specifies the color/intensity value to use to draw lines.

     The default draw value is 1.

     For monochromatic displays, only the low-order bit of the draw value is
     considered because monochromatic displays have only one plane.

     For color displays in 4-bit pixel format, only the four lowest-order bits
     of the draw value are considered because these displays have four planes.

   Input Parameters
     color
          The color to be used for drawing lines, in gpr_$pixel_value_t for-
          mat.  This is a 4-byte integer.  Valid values are

             ⊕  0 - 1 For monochromatic displays.

             ⊕  0 - 15 An index into a 4-plane color table.

             ⊕  0 - 255 An index into an 8-plane color table.

             ⊕  0 - 4096 An index into a 12-plane true-color table.

             ⊕  0 - 16,777,215 A color value for a 24-plane true-color pro-
                gram.

             ⊕  -1 For all displays.  This specifies that the background is
                transparent; that is, the old values of the pixels are not
                changed.

             ⊕  -2 For all displays.  This sets the drawing value equal to the
                color of the bitmap background.  For borrowed displays and
                memory bitmaps, the fill background is always zero.  For
                Display Manager frames, this is the pixel value in use for the
                window background.

   Output Parameters
     status
          Completion status, in status_$t format.

SEE ALSO
     gpr_$inq_draw_value.

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026