[vtkusers] Re: timer example

[Goodwin Lawlor]

Dominik Szczerba wrote:
> According to the docu, the vtkHoverWidget is used to invoke an event when 
> hovering in a render window. Do you propose to use a zero threshold to 
> simulate an idle function? That sounds like an overkill for what I need. Iren 
> allows for timers, is there really no way to regularly trigger arbitrary 
> commands just like iren->AddObserver(vtkCommand::MouseMoveEvent, myCommand) 
> does on a mouse movement?

Hi Dominik,

I meant vtkHoverWidget is the only that uses a repeating timer at the 
moment. Here a (slightly buggy) but quick tcl example to illustrate:

package require vtk
wm withdraw .

set val 10

vtkTextActor txt
   txt SetInput $val
   txt SetMinimumSize 100 100
   txt ScaledTextOn

vtkRenderer ren
   ren AddActor txt

vtkRenderWindow renwin
   renwin AddRenderer ren

vtkRenderWindowInteractor iren
   iren SetRenderWindow renwin
   iren Initialize

   iren CreateRepeatingTimer 1000
   iren AddObserver TimerEvent {if {$val == 0} exit}
   iren AddObserver TimerEvent {txt SetInput [incr val -1]; txt 
Modified; renwin Render}

hth

Goodwin