Breaking out of a loop

sdmitch

Is there anyway to duplicate the VB's DoEvents in a Ruby script? I have been trying to figure out a way to interupt a loop. I have tried most if not all of the 'on' tool options but none have succeeded in breaking out of a loop.

Dan Rathbun

see the Ruby keyword break:
http://www.ruby-doc.org/docs/keywords/1.9/Object.html#method-i-break

sdmitch

Thanks Dan. I am familiar with break and have it inside my loop. The problem is I want the trigger for the break has to come from outside the loop which is why I have attempted to use all the 'on' tools to set the trigger but they seem to be ignored until the loop terminates on its own.

Dan Rathbun

Well .. there is not much help we can give you without some sort of example. Or at least explaining what you want to do in psuedo-code.

"on tools" I think you are meaning the various Observer callbacks ??

sdmitch

Dan, I didn't make myself very clear. The 'on' tools are onKeyDown, onKeyUP, etc. When the code is running, I wanted to stop the spinning when I pressed a key and resume it when I released the key. But the onKeyDown doesn't execute until the spin_it method times out. I have also tried all the ButtonDown and Ups with the same results.

class Spinners
 def activate
  mod = Sketchup.active_model
  ent = mod.entities
  sel = mod.selection

  @corg=[]
  sel.each{|e| @corg<<e if e.class==Sketchup;;Group || e.class==Sketchup;;ComponentInstance}
  sel.clear;@stop_spin=false;@start_time=Time.now;self.spin_it
end
def spin_it
  begin
   @corg.each{|e|
   tr=Geom;;Transformation.rotation(e.bounds.center,Z_AXIS,1.degrees)
   e.transform! tr
   }
   Sketchup.active_model.active_view.refresh
   break if @stop_spin
   sleep(0.1)
  end until Time.now - @start_time > 10
 end
 def onKeyDown(key,repeat,flags,view)
  @stop_spin=true
  puts "stopped"
 end
 def onKeyUp(key,repeat,flags,view)
  puts "started"
  @stop_spin=false
  @start_time=Time.now
  self.spin_it
 end
 def onCancel(flags,view)
   Sketchup.send_action "selectSelectionTool;"
 end
end
UI.menu("Plugins").add_item("Spin_It") {Sketchup.active_model.select_tool Spinners.new}

Dan Rathbun

Oh OK.. it might work better if you put everything inside the spin_it() method within a UI.start_timer block.
see: http://code.google.com/apis/sketchup/docs/ourdoc/ui.html#start_timer
also take note of UI.stop_timer()

sdmitch

Thanks again Dan. I think the start/stop_timer may be the solution to the problem. However they are apparently not without pitfalls. My first try ended up starting the timer with repeat set to true and not stopped before the plugin exited so my object continued to spin.

Dan Rathbun

@sdmitch said:

... and not stopped before the plugin exited so my object continued to spin.

Well you need to add deactivate() and suspend() callbacks that stop the timer block. Your timer id will need to be an @var (instance variable.)

P.S.: The timer blocks are the only "thread-like" mechanism in the API.

Jim

Don't forget about the Animation class - it could also have been used instead of a time.

TIG

Shouldn't you swap the results of the key-up and key-down events ?
You hold the key down it spins, release it and it stops ?
Take the self.spin_it out of the activate method, it's run when there's a key-DOWN event anyway.
When there's a key-UP event it sets @stop_spin=true, so the 'until test' should expand to be until Time.now - @start_time > 10 **or** @stop_spin
and you should remove the matching break from inside the loop too as the until breaks it anyway...