# Random dots plugin

**URL:** <https://mworks.discourse.group/t/random-dots-plugin/520>\
**Category:** Support\
**Created:** [May 22, 2015, 3:53pm UTC](https://mworks.discourse.group/t/random-dots-plugin/520 "2015-05-22T15:53:24Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\
**Post date:** [May 22, 2015, 3:53pm UTC](https://mworks.discourse.group/t/random-dots-plugin/520/1 "2015-05-22T15:53:24Z")

</div>

Hi Chris,  
I’ve been playing around a bit with the random dots plugin.  
It works fairly well.  
I only have a couple of questions about it.

As i understand, it misses a wrap-around parameter (i.e., when a dot that hasn’t finished its lifetime moves outside the stimulus aperture, it isn’t redrawn on the opposite side). Does the plugin provide a new dot in a random position, in this case? Otherwise the density could vary a bit at each frame…

How did you compute the random directions of the non-coherent dots? I had the impression (but I understand it can just be an impression) that some directions are more represented than others and this creates “streams” of randomly moving dots along few directions.

Finally, I tried to copy&paste the plugin in the MW 0.5.1 version, but of course it didn’t work (it gave me an ‘Unknown attribute “announce\_stimuli\_on\_implicit\_updates”’ error). Is there any way to use the randomdots plug-in in a non-nightly build version of MW?

Hope everything is clear!  
Thanks in advance  
Bw  
Rosilari

---

<div class="post-metadata">

**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\
**Post date:** [May 22, 2015, 8:46pm UTC](https://mworks.discourse.group/t/random-dots-plugin/520/2 "2015-05-22T20:46:00Z")

</div>

Hi Rosilari,

> As i understand, it misses a wrap-around parameter (i.e., when a dot that hasn’t finished its lifetime moves outside the stimulus aperture, it isn’t redrawn on the opposite side). Does the plugin provide a new dot in a random position, in this case?

When a non-expired dot drifts out of the field, a new dot drifts in. The new dot is assigned a random direction and age (subject to your specified coherence and lifetime), so it can enter the field at any location compatible with its direction.

> How did you compute the random directions of the non-coherent dots? I had the impression (but I understand it can just be an impression) that some directions are more represented than others and this creates “streams” of randomly moving dots along few directions.

For non-coherent dots, the plugin picks the direction by drawing a random floating-point value from a uniform distribution over the range [0, 360).

> Is there any way to use the randomdots plug-in in a non-nightly build version of MW?

No, it’s only available in (and compatible with) the nightly build.

Cheers,  
Chris

---

<div class="post-metadata">

**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\
**Post date:** [May 23, 2015, 1:44pm UTC](https://mworks.discourse.group/t/random-dots-plugin/520/3 "2015-05-23T13:44:01Z")

</div>

Thanks a lot!  
Rosilari

---

<div class="post-metadata">

**Author:** ![cstawarz](https://yyz1.discourse-cdn.com/flex031/user_avatar/mworks.discourse.group/cstawarz/32/3_2.png) [@cstawarz](https://mworks.discourse.group/u/cstawarz)\
**Post date:** [July 19, 2022, 10:40pm UTC](https://mworks.discourse.group/t/random-dots-plugin/520/4 "2022-07-19T22:40:32Z")

</div>