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PAD_$SET_SCALE                    Domain/OS                     PAD_$SET_SCALE


NAME
     pad_$set_scale - set a scale factor for cursor operations

SYNOPSIS (C)
     #include <apollo/base.h>
     #include <apollo/pad.h>

     void pad_$set_scale(
          ios_$id_t &stream_id,
          short &x_factor,
          short &y_factor,
          status_$t *status)

SYNOPSIS (Pascal)
     %include '/sys/ins/base.ins.pas';
     %include '/sys/ins/pad.ins.pas';

     procedure pad_$set_scale(
          in stream_id: ios_$id_t;
          in x_factor: integer;
          in y_factor: integer;
          out status: status_$t);

SYNOPSIS (FORTRAN)
     %include '/sys/ins/base.ins.ftn'
     %include '/sys/ins/pad.ins.ftn'

           integer*4 status
           integer*2 stream_id, x_factor, y_factor

           call pad_$set_scale(stream_id, x_factor, y_factor, status)

DESCRIPTION
     Pad_$set_scale sets the display scale factor for a pad.  Many pad_$ sys-
     tem calls use a scale factor to convert argument values from a measure
     that is more convenient for the user into the raster units used by the
     Display Manager.  A raster unit is the smallest addressable area of the
     display.

     When a pad is created, its scale factors are equivalent to the dimensions
     of the pad's current font, so that scaled system call arguments are
     interpreted as character and line counts.  This default scaling can be
     restored by calling pad_$set_scale with scale factors of 0.  Scale fac-
     tors persist as long as the stream is open; they are not reset to the
     font dimension default when a program that has altered them terminates.
     Therefore, a program should probably set the scale factors it needs when-
     ever inheriting pads from other programs.

     stream_id
          The stream ID the pad is open on.

     x_factor
          Scale factor for the horizontal coordinate.  Setting x_factor to 0
          restores the default horizontal scale factor.  The default horizon-
          tal scale factor is the horizontal dimension of the current font
          expressed in raster units.

     y_factor
          Scale factor for the vertical coordinate.  Setting y_factor to 0
          restores the default vertical scale factor.  The default vertical
          scale factor is the vertical dimension of the current font expressed
          in raster units.

     status
          The completion status.

SEE ALSO
     pad_$inq_font, pad_$inq_view, pad_$locate, pad_$move, pad_$set_tabs,
     pad_$set_view, pad_$use_font.