In the last Rhino 8 Wip Release (4.4.2023) the command “_ExtendSrf” became almost unusable for me, as it extends all the edges of a (trimmed) surface, instead of just extending the selected one. In Rhino 7, on the very same file, _ExtendSrf works exactly as expected. Please see attached images. :…

@gian Run UntrimAll on the surface and ExtendSrf should behave normally. It appears that the surface was imported as a trimmed surface, even though the trimmed edges coincide with the untrimmed edges. This does not usually occur in Rhino. However it should not cause a problem. Would it be okay for …

PS: Exact Rhino 8 Wip Release is 8.0.23094.11475, 2023-04-04 I also attach sysinfo: Sysinfo.txt (2.5 KB)

ExtendSrf appears to work properly for me in WIP. Can you provide an .3dm file with an example of a surface for which ExtendSrf does not work as expected in WIP?

Hi David, I attach here a couple of videos illustrating what happens to me when I try to extend A SINGLE EDGE of a simple (yet cutted) surface. I can’t extend the single edge: the command behave in a totally weird way and extends ALL the edges anyways, whatever edge I specify. Consider that in Rhi…

Sysinfo is always from my DELL T7600 with updated video drivers. Sysinfo DELL T7600 - DRIVERS 2023.txt (2.7 KB) PS: In the previous post I added the third video, showing the “normal” way command executes in Rhino 7. Could you please check @davidcockey ?

A .3dm file with an example of a surface for which ExtendSrf does not work as expected in WIP would be very helpful to anyone who attempts to help you.

Ops you are right David. I prepared it but I forgot to send it here: it’s just the surface you see in the videos. I’ll attach it to te next message in just some minutes…

Here it is @davidcockey … Surface failing ExtendSrf.3dm (65.2 KB)

Hi, It looks like the surface is imported from another 3d modelling software, and that It keeps referencing the OG surface (kinda looks a hull to me, and I experienced that same issue many times) To resolve this : we dup 2 edges, extract a few isocurves, then loft the curves and we have new clean …

Thank you @farouk.serragedine for your contribute! And welcome on the magical mistery tour of “extendsrf” :slight_smile: Actually you hit one point: the original file was from a different CAD (solidworks, I reckon). And your solution for sure helps as a workaround in Rhino 8 WIP. But in my opinio…

Hello @davidcockey Thank you really much: you got the easy way, as “Untrim all” worked immediately and is a simple operation. Of course this is a better workaround but is, indeed, a workaround: very useful to save the work from longer solutions, but yet a regression in comparison to Rhino 7. Usel…

"_ExtendSrf" command weird behaviour in Rhino 8 WIP (Bug)

Serengeti (Rhino WIP)

davidcockey (David Cockey) April 7, 2023, 1:54pm 14

The problem appears to be with many or all trimmed surfaces in the current version of V8 WIP. I started a new thread about it. ExtendSrf on trimmed surfaces - major bug

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"_ExtendSrf" command weird behaviour in Rhino 8 WIP (Bug)

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