Hi Balakay612,

The first idea is typically either Ray-Switch or the RS Render Tag. Anything in "post" is possible, but in all three options, there are some problems.

The main problem is that the visibility of the object is based on the camera position, but what is seen from the camera in a reflection has a different perspective. In your images, I see flat objects, which simplifies the perspective problem.

Please have a look here:
CV4_2025_drs_25_RSvs_01.c4d
Screenshot 2025-05-28 at 11.37.21 AM.jpg

The key is to have sufficient resolution in the object to produce a smoother "transition" between visibility and invisibility.

The camera is the key point here, and with the "Move_Me" target, the Field Cone is positioned as needed.

This Field Cone defines the Vertex map of the object. The created data can be used to drive aspects of the material, such as opacity.

I used a 3D object (not flat) here to showcase the limitation, but with flat objects, as mentioned, that should work.

Similar to that might work a front projection with an animated "mask" video-file.

All the best

Hi Blake,

I am not on my computer as I am visiting the Maxon Summit this week. So I have to do what I think is not the best way to do it—guessing. Sorry about that.

Having a whole scene (or a larger group) in a Boole might not work when one part is not ready for this.

Take the most complete object and test if a cube can Boole it. Perhaps with the group either under a Connect Object or Booled first, or even merge all first. Those three might hold one option to explore further.

Please note that Multi Instance might be source of trouble here, if the Cloner is set to this.

Edit: back in California, here is an example
CV4_2025_drs_25_ANsb_01.c4d

OR load the file …_11.c4d as Xref into …_21.c4d
CV4_2025_drs_25_ANsb_11.c4d
CV4_2025_drs_25_ANsb_21.c4d
Screenshot 2025-05-23 at 8.53.45 PM.jpg
/edit

My best wishes

You're very welcome, Balakay612,

Please always feel free to ask. If it is an easy thing to answer, it is no effort; if it is complicated, it is typically time to answer it.

Keep in mind that others might have the same question at one point, and then, based on an earlier question, an answer is already there.

Enjoy.

Hi Balakay612,

Thanks for the feedback.

Here is a less precise but much easier way. You might find the Range Mapper tuned accordingly. This means, set a start point of the radius and end point while defing the amount of start and end step.
To fine-tune it, adjust the Spline Curve of the Rangemapper.

An example is here:
CV4_2025_dr_25_XPsc_11.c4d
.

About the file from the earlier post:

I used the Formula Node here, as it allows me to keep things compact.
This could be done with single Math Nodes, which might make it easier to read.

I needed to know the circumference of your reference setup, which would be the 360º of the 3668 radius (Radius 2 PI = Circumference)

With that, I was able to define step length using the 21º you have set up and the step count. ((Circumference*21º)/360º))/ Step-count = Length of a Single step or stair element.

Now, I needed to place that into a formula to have a different Radius driving the number of steps needed to fill the 0º to 21º you have as your fixed boundary.

I hope that helps untangle the XPresso a little bit.

Yes, sometimes Math comes in handy.

Enjoy

Hi Balakaya612,

So, the error is based on using two Output Objects.

My suggestion would be to write OpenVDB files out and use materials as you need those. This is a wild guess, because:

I struggle to see how that is even remotely working in a believable visual way (not to talk about physics by now), as the different scatter results must be based on differences in the sources. How those sources and their obviously and requested different results (e.g., Scatter) would not interfere with each other in such a dynamic scenario is beyond me. But with separate setups, that is not a give; perhaps introducing Particles into the mix might help. My theoretical (or call it a wild guess) conclusion is that it will not work if I just use two independent sources.

Perhaps the best way to explain it would be to use the dynamics and complexity of weather prediction, which is also based on air movements. Which is so complex that we struggle to make long-term predictions.
Now, with sources, the turbulences and the complexity are limited but interactive. It does not influence the other; that influence affects an infinite loop. How much that can be recognized is unclear to me, as it is a question of perception and the level of detailed observation, but it surely is not a single bilateral effect.

Perhaps you have some reference photos that show how that works so I can explore it.

Cheers

Thanks for the reply as well, and taking the time, Balakay612.

My best wishes for your project!