The variable _draw3 and the idler

_draw3 is an internal 3D PyGist variable accessible to the user only by means of the access functions described below. _draw3, in conjunction with a function called an idler, determines whether, after a plot function and its arguments have been placed on the display list, some further action takes place. The default idler (see below) will cause the graph to be plotted each time it is called; and it will be called immediately after the plot function has been added to the display list, provided _draw3 is nonzero.

Calling Sequences

...

 
set_draw3_ (n) 
n = get_draw3_ ( )

Description

The first function is used to set _draw3 to n (default 0), and the second, to read its current setting.

Calling Sequences

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clear_idler ( ) 
set_idler (func_name) 
set_default_idler ( ) 
call_idler ( )

Description

The function clear_idler sets the idler function to a routine which does nothing. It will be called after each plot function adds to the display list (if _draw3 is nonzero), but will do nothing. set_idler allows the user to define an action for 3D PyGist to take after each plot function call adds to the display list. func_name must be callable with no arguments. It will be called only if _draw3 is nonzero. set_default_idler will set the idler to call the function whose code is given below. call_idler gives you the capability to call the idler yourself, if you wish.

The Default Idler

Below is the code for the default idler.

def _draw3_idler ( ) : 
global _default_gnomon 
orient3 () 
if current_window () == -1 : 
window3 (0) 
else : 
window3 (current_window ()) 
gnomon (_default_gnomon) 
lims = draw3 (1) 
if lims == None : 
return 
else : 
limits (lims [0], lims [1], lims [2], lims [3])