As you can see in the video, I have a very clean network surface. But when I use FlowAlongSurface it becomes very dense, which is a big disadvantage for FlowAlongSrf. Cand this be improved or avoided? (I cannot PreserveStructure=Yes in this case, because my edges won’t match) FlowAlongSrf No Pre…

Time is not a good metric. It would make the result different on different devices. Did you try lowering the document tolerance and flow both with preserve=no?

[image] Bogdan_Chipara: How would you know how to pick between preserve yes and preserve no well, your green has almost no points to deform, whereas the black has. So with preserve= yes for the green Rhino cannot modify that surface enough to match it with the target surface’ shape.

So the cool thing would be… what if Rhino has another mode for FlowAlongSrf that makes the right decision for the user? Because if you have 100 surfaces, is pretty tedious to manually pick between Yes and No. You would like to pick all of them and flow them in one go.

[image] Bogdan_Chipara: another mode for FlowAlongSrf that makes the right decision for the user what is the metric for right? Rhino is not aware of what you are deforming or any condition you have between the objects you are deforming.

I know… I’m describing a problem here… not offering a solution. Problem: If there are 100 surfaces to FlowAlongSrf, The user will have to test for each of those surfaces twice. That means 200 operations and Not Responding states. If FlowAlongSrf is solved “correctly” by the software: User can fl…

I know it is tedious, but sometimes there is no way around it. If you cannot define what ‘correctly’ means, how can we even start thinking about automating it? Currently Rhino will increase the complexity based on the metric ‘tolerance’. It keeps increasing the complexity of the surfaces until it me…

For sure something can be done.. being optimistic. What if: If Rhino starts to increase the complexity, after a certain iteration, it automatically switches to the other method. For example, it starts with Preserve=No it reaches a certain complexity, abandons the operation and switches to Perserv…

Rhino’s metric to decide when to stop is absolute tolerance. If you can define another metric, I could log it for the developer working on these transformation tools. All UDT tools are using this tolerance to decide whether or not to refine the result, as demonstrated in the image I posted.

What if something like: Given 100 surfaces, for each surface, run FlowAlongSrf with Preserve=No on a custom tollerance which is very very low (or let’s say user can decide it). When geometry exceeds the custom tollerance, switch to Preserve=Yes. This way the user has an opportunity to adjust whe…

What you propose is not a new metric, Rhino already works this way. It will refine the result only if it exceeds the file tolerance.

The NetworkSrf can be created using the 4 curves and setting the Edge curves tolerance to 1. (Model tolerance is 0.001.) [image] If a loose tolerance can also be used to create the transformed surface, a couple ways to do this are: _FlowAlongSrf (with PreserveStructure=No) the NetworkSrf’s inpu…

FlowAlongSrf PreserveStructure=No - very dense result - why?

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Bogdan_Chipara January 19, 2026, 3:11pm 33

@Gijs you made me do another “GPT slop”…

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FlowAlongSrf PreserveStructure=No - very dense result - why?

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