Update Variable Watcher Display?

Help with Snap!
1

Is there a way to cause a script to wait until the variable watcher display updates before continuing?

I am incrementing a variable in a loop by 1, but the watcher display only updates every second or third iteration:

 1, 3, 5, 8, 10

Here's a link to a video that shows the result:

   https://www.dropbox.com/s/we2ztwnicsl78qo/Ping%20Pong%20Balls.mp4

I added a tenth of a second delay, but that did not change the behavior of the watcher variable display.

2

You could make your own "watcher" by using the write block:

untitled script pic (3)

@jens or @bh might know if it is possible force a watcher to update.

3

Yes, as @legoman3.14 has said, maybe the best way is to build your own construction.

Aside this, if you want to force watchers updating, you can use this

updateWatchers

Joan

4

The first thing is, don't use WARP or Turbo mode; those work by stealing time from screen refresh, so they pretty much guarantee that the watcher won't keep up.

5

Thanks for the helpful suggestions. I am not using WARP or Turbo mode, so that is not a factor.

  1. I found that a delay of 0.4 seconds was needed to allow the watcher to consistently update between each iteration.

  2. The suggestion to create a watcher using the Write command worked even with the delay set to 0 seconds.

Evidently the Write command can update more quickly than the variable watcher? In any event, thanks for the input and recommendation for a solution that worked.

6

Updating watchers could absorb all the available time if allowed. So it's done once in a while. With WRITE, it's not that the updating is quicker; it's that this is a change the user asked for explicitly, so it's more urgent.

7

That makes sense ... thanks for the explanation.

Jguille2 provided JavaScript code (above) to force a watcher update. I am not familiar with the ExecuteA code block used in this example. Is the ExecuteA code block an extension or part of a block library, and is there documentation or an example describing it? (Thanks)

8

It's Catalan for RUN.

9

Joan uses the RUN block in a Catalan translation :slight_smile: RUN, CALL and LAUNCH are very much part of Snap's primitives and well supported / documented.

I'm not sure I understand about the underlying problem. We're only updating the watcher displays about 3 times per second, but that's just the display, the value changes instantly. Is this a problem?

10

Oh sorry... I forgot to switch to English for the snapshot :slight_smile:

Yes, it's only "Run".

That JS code is just Snap! code. But it is not necessary to learn it. You can choose your work... and you can change it anytime you want.

  • Using other Snap! features to do it, as write block, or say... And doing what you want to do, controlling all what you do.
  • Using that JS code, building a new custom block, to get exactly what you want. And maybe you don't know how create that code. Using it as a primitive or a library.
  • Learning Snap! code and being able to do anything you want.

Yes I love Snap! because I can choose every moment what I need or what I want.

Joan

11

Glen wants to use the watcher as a component of a user interaction. Think about putting 5 in a variable, drawing a pentagon; putting 6 in the variable, drawing a hexagon; etc. But it's okay, @legoman3.14's solution of using WRITE instead of the watcher solves the problem.

12

The JavaScript to force an update of the watcher worked like a charm (once I understood that the Catalan label for the code block was the equivalent of "Run" in English). Thanks for the assist!