Cancel system.gui.transform

Ignition
#1

I’m using system.gui.transform with a duration to move a container to X,Y positions supplied by PLC tags. This works, except when I begin a new movement with another system.gui.transform before the previous move has completed its duration. Then I see erratic behavior with the container quickly bouncing back and forth between the two destinations before ultimately landing on the newest one. Is there a way I can cancel the transformation in process before executing a new one? Or another method to handle this case?

Function I am using:
system.gui.transform(container, newX, newY, duration=5000, acceleration= 4)

Ignition 7.9.12

#2

One of the original applications for objectScript() (from Simulation Aids) was precisely this sort of animation. (Animation via system.gui.transform() didn’t exist yet.) Instead of computing a complete series of steps and applying them unconditionally on a fixed pace, the approach with objectScript() is to maintain a state machine and compute each step as it occurs. It is more complicated to implement, but handles any change in target gracefully. You can even model the acceleration on a curve from one target to the next. The demo project has an example (without accel) on the last tab.

#3

I created and posted a 40-second video using the SimAids demo project showing the animation:

https://www.automation-pros.com/simaids/SimAids-MotionDemo.mkv

#4

From the manual (system.gui.transform):

  • Returns
    PyObject animation - An animation object that the script can use to pause(), resume(), or cancel() the transformation.

Is that what you’re looking for?

1 Like
#5

Thank you Phil. I’m on the road this week, but will examine this module when I return.

#6

It may very well be, but I could not figure out how to implement it.

#7

Well, it shouldn’t be so hard… :wink:

  1. Create client project script in ‘Scripting/Project Library/’ (Ignition8) or ‘Project/Scripts/Script Library’ (Ignition7.9) with the name ‘global_variables’
  2. Put this inside:
_transformObject = None
  1. On the Vision window put rectangle box and 4 buttons.
  2. Name buttons as ‘Start’, ‘Pause’, ‘Resume’ and ‘Cancel’.
  3. In the ‘Start’ button ‘ActionPerformed’ event put this code:
event.source.parent.getComponent('Rectangle').relX = 50
project.global_variables._transformObject = system.gui.transform(component=event.source.parent.getComponent('Rectangle'), newX=710, duration=10000, acceleration=system.gui.ACCL_FAST_TO_SLOW)
  1. In the ‘Pause’ button ‘ActionPerformed’ event put this code:
if project.global_variables._transformObject is not None:
	project.global_variables._transformObject.pause()
  1. In the ‘Resume’ button ‘ActionPerformed’ event put this code:
if project.global_variables._transformObject is not None:
	project.global_variables._transformObject.resume()
  1. In the ‘Cancel’ button ‘ActionPerformed’ event put this code:
if project.global_variables._transformObject is not None:
	project.global_variables._transformObject.cancel()

And that’s it…

transformCancelResume
transformCancelResume.gif801×603 752 KB

1 Like
#8

This is a great example. Thanks. I had some time today to attempt this, but I do have 50 objects moving on my screen utilizing this method and I still see too much erratic behavior. I am able to significantly decrease this behavior by doing the transform with a newX and newY without a duration (so it happens immediately and is over). Some examples of the problems I see in addition to the jerky movement are the containers being briefly invisible and also them falling behind other objects even though they are on top.