Full Arc At Current Position; Image Data - IBM 6400 Programmer's Reference Manual

Graphics Command Set

Full Arc at Current Position

Description: This order specifies a full arc (circle or ellipse) with the center at
the current graphics position. A previous Set Arc Parameters order determines
the shape and orientation of the arc. If no Set Arc Parameters order has been
received, then the printer draws an arc using the default values of the arc
parameters.
Parameters P1 and P2 form a two byte value that specifies the scale. P1
specifies the integer portion of the scale; P2 specifies the fractional portion of the
scale (P2 divided by 256). For example, if P2 equals X
P2 is 64. This value (64) divided by 256 equals the fraction one-fourth.
The scale value acts as a multiplier for the arc parameters. For a circle, the
radius is P1P2 x r. A previous Set Arc Parameters order specifies the value of r.
For an ellipse: The major axis is P1P2 x a, the minor axis is P1P2 x b, and a
previous Set Arc Parameters order specifies the values for a and b.
The printer uses the current values of color, mix, line type, and line width when
drawing the arc.
This order does not update the current graphics position.

Image Data

Description: This order specifies the image data for all or part of an image
introduced by a Begin Image order. A Begin Image order must precede an
Image Data order.
L1 is a one-byte value that specifies the length (in bytes) of the image data that
follows. Valid values for L1 are X
Parameters P1 to Pn are values that specify the image dot data, a zero
indicating the absence of a dot, a one indicating the presence of a dot. The dots
are 0.18 mm (0.007 in.
The image data is in the form of horizontal scan lines (rows), left to right. Each
Image Data order specifies only one scan line (row) of the image. Therefore, the
number of Image Data orders following a Begin Image order must be equal to
the value specified in parameters P5 and P6 (the image height) of the Begin
Image order.
Each of the parameters, P1 to Pn, of the Image Data order specifies eight dots.
Therefore, parameter L1 of the Image Data order must equal the image width
divided by eight. Parameters P3 and P4 of the Begin Image order specify the
image width. If the image width is not a multiple of eight, the printer ignores any
extra dots specified by bits in the last parameter, Pn.
Note: The image data specified in the Image Data Orders between a Begin
Image and End Image pair must exactly fill the area specified by the width and
height of the Begin Image order.
104
6400 IPDS
87 L1 P1 P2
92 L1 P1-Pn
[ 1/144 in. ] ) apart horizontally and vertically.
' 40 ' , the decimal value of
' 00 ' through X ' FF ' .