Rohan Dalvi - Rocketship Tutorial in Houdini 16 (and the Group Node)

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Hello,

since there aren't too many extensive tutorials on Houdini (especially newer versions), I decided that I would follow Rohan Dalvi's series and just learn along the way.

Since I'm only just starting with the tutorial, I wonder if it's okay to keep this thread as a general thread for any questions that are related to this tutorial series and changes to Houdini 16.

Now I already figured out that Rohan is using an older group node that is obsolete and should not be used anymore, but I can't really figure out what node to use and how to get the same effect. It's very simple, I basically need to create the settings as seen in the attachment. (Create a Group with “top” as Group Name, Points as Entity and a Pattern of 1.)

Thank you for any help, and excuse me for asking such a simple question.

Attachments:
rohan_dalvi_rocketship_group.jpg (155.5 KB)

Houdini FX Apprentice 16.0.504.20
Windows 10 Pro 64 Bit
i7 6700k @ 4.5GHz
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You can still use those nodes - line and group in H16.
I believe in H16 if you use the CopyStamp node you will get the equivalent.
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I couldn't find the old Group Node in the Tab Menu.

The Copy Stamp node doesn't provide me with the same parameters that I see in the video.

Attachments:
copy_stamp_node.png (791.3 KB)

Houdini FX Apprentice 16.0.504.20
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All the group node is doing in Rohan's example is selecting point # 1, and naming it top. In h16 if you drop the new group node you'll see a base group field, you can type 1 there (and change group type to points), and it will do the same thing as the old group.

Another tip, anytime you drop a node and it lets you choose a group, usually at the top, you can enter a pattern directly, pattern is just the points/primitives numbers, ie type “1-10” and houdini will automatically create a group base on the group type.
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Thank you so much, I get it now!

I also realise that I posted this in the wrong board.
Houdini FX Apprentice 16.0.504.20
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Hi there.
Guys i'm total noob, I've just started to follow some tutorials.
I have this problem with the new group node in houdini 16.
How can i use this “filter expression” in H16 ? please help
when i write “rand($PT) > 0.5” in group node / base group it doesn't work.
It's not working in “group expression” too
I could not find any answer in google.
This is a screenshot from tutorial.

http://imgur.com/a/HVJ59 [imgur.com]
Edited by Alfheimr - March 17, 2017 12:40:22
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Group Expression uses VEX, instead of HScript and local variables. rand(@ptnum) > 0.5 seems to work.
Edited by neil_math_comp - March 17, 2017 13:10:40
Writing code for fun and profit since... 2005? Wow, I'm getting old.
https://www.youtube.com/channel/UC_HFmdvpe9U2G3OMNViKMEQ [www.youtube.com]
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hah, stupid me : D
Thank you for your prompt reply man : )
Cheers to you !
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I working on the rocket ship tutorial and I'm stuck on the section where the cable is created. I'm trying to create a group that contains the first and last points of a line. In the tutorial, Rohan uses 0 and $N. The 0 works, but the $N doesn't. I've tried points(0)-1, but that didn't work either. Has anyone been able to figure this part out?

Thanks.
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With Group Expression:

@ptnum == 0 || @ptnum == npoints(0)-1

Alternatively, with a regular Group field, or with the Base Group field on the Group Create SOP:

0 `npoints(0)-1`
Edited by neil_math_comp - April 18, 2017 01:08:29
Writing code for fun and profit since... 2005? Wow, I'm getting old.
https://www.youtube.com/channel/UC_HFmdvpe9U2G3OMNViKMEQ [www.youtube.com]
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Thanks. I was using the `npoints(0)-1` but was using the wrong quotes.
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GroupRangeSOP

Start slider = 1
End slider = 1
Invert Range checked.
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