Graphics Verbs

The complete information about the following verbs can be found in the chapter 15.
 autoscale
The window limits and the tick marks are adjusted (sec. 15.3.3). The tick marks are adjusted. The window limits are changed only by an amount that is less than a tick distance.
 change
Invokes a full screen menu. The attributes that can be changed are displayed - with the exception of the /pairs flag and the axis descriptions of SCANs (sec. 15.3.6).
 change layout
There are attributes that apply for all graphical queue elements, e.g. tick mark length, grid colour, distance between the axes and the big tick mark numbers. These attributes are stored in CONST GQEs. One CONST GQE named layout is automatically created by the first display command of a session. It is stored in slot 0. In most cases it is sufficient to have one layout. However, the user can copy layout from slot 0 into the slot of any SCAN and change the items of the new GQE. These are then valid for the graphical representation of the GQEs in that slot. The following example illustrates, how a grid can be enabled for a particular SCAN:
SPECTRA> read bpu1 
SPECTRA> read/asc/notext alhe01 
SPECTRA> cop layout 2 
  The layout from slot 0 is copied to the second slot.

SPECTRA> set 2.layout/grid_col=1 
  The grid colour is set to black. 

SPECTRA> set alhe01/v2/y_max_view=0.8 
  The viewport of alhe01 is set to the upper right corner. 

SPECTRA> set alhe01/x_maj=-attr(2,x_maj)/y_maj=-attr(2,y_maj) 
  The major tick mark factors of alhe01 are set to their  
  negative values in order to suppress the numbers at 
  the axes. 

SPECTRA> display
The figure 10.2 show the resulting plot.
 copy/attributes
Copies all graphical attributes from one SCAN to another .(sec. 15.3.14).
 copy/window
Copies the window limits from from one SCAN to another .(sec. 15.3.14).
 deactivate
Deactivated GQEs are ignored by display or Postscript commands until an activate command is issued .(sec. 15.3.22).
 display
The queue elements are displayed (sec. 15.3.22).
 gks
Invokes a full screen menu which allows to change the default graphical attributes.
 graphic
This command is useful for ATARIs and FALCOs. It switches the terminal to the graphical screen (sec. 15.3.37) .
 overlay
One SCAN is displayed in the window limits of another an no axes are displayed for the SCAN (sec. 15.3.50).
 set
One or more attributes are changed. The qualifiers can be found by ”help set attr ". The counterpart to the set command is the attribute() function which retrieves the values of the attributes (sec. 15.3.69).
 set bg_colour
Sets the background colour (sec. 15.3.69).
 set colour
Changes the RGB contents of a colour cell (sec. 15.3.69).
 set display display_name
Changes the destination of the X11 output (sec. 15.3.69).
 set gks/...
Sets the default GKS attributes that are used when a GQE is created.
 set term/...
Change the terminal attributes (sec. 15.3.69).
 set ws viewport ...
Sets the workstation viewport, i.e. the size of the device.
 show/ct
Displays the parameters of the x-terminal (sec. 15.3.72).
 show/ct
Shows the colour table entries (sec. 15.3.72).
 x11
Changes window attributes (sec. 15.3.84).
 zoom
SCANs can bee zoomed using the arow keys (sec. [*]).

Figure 10.1: Using two layouts, code on sec. 10.2
Image layout_example