blocks in GH?

Hi all,

Is it possible to operate on blocks in Grasshopper?

thanks,

JJ

Replies to This Discussion

Permalink Reply by David Rutten on September 4, 2009 at 12:44pm

No.

--
David Rutten
david@mcneel.com
Robert McNeel & Associates

Permalink Reply by Jacek Jaskólski on September 4, 2009 at 3:05pm

Hi David,

And what about some indirect way, using VB.Net components or combining them with Rhinoscript?

I tried to play with it a bit (see example below), but it seems that i don't get the concept behind those components just quite yet..

Here's what I tried to achieve:

1. Copies of geometry positioned, scaled and orientedon on a path,

2. Same thing but using block instances

I tried using "RhUtil.RhinoApp.Insertblock" but as it turns out it won't work.

It would be nice to get the result of a grasshopper definition as block instances. This is just an example but I think it could be very useful especially for further editing and exporting to other programs.

Q1: Is there a method to do it from within the VB.net component?

If not, the task could be achieved by exporting data (containg positions and transformation matrices) from GH to an external file, and later feeding the data to a script in Rhino.
Q2: Is all this worth the hustle, or am I just far up a blind alley?

Thanks again,

JJ

//should the discussion be moved to the VB corner?

Permalink Reply by Vicente Soler on September 4, 2009 at 4:31pm

Yes.

The following code should extract all breps in a block. Create a GUID parameter, right click on it and select 'set one Guid', then select the block instance. Connect the Guid parameter to the 'x' input of a VB component and use this code:



Dim brep_list As New List(Of OnBrep)

Dim objref As New MRhinoObjRef(New Guid(x))

Dim iref As IRhinoInstanceObject = MRhinoInstanceObject.ConstCast(objref.Object)

Dim idef As IRhinoInstanceDefinition = iref.InstanceDefinition

Dim objects(0) As irhinoobject

Dim count As Integer = idef.GetObjects(objects)

For i As Integer = 0 To count - 1

brep_list.Add(objects(i).Geometry.brepform)

Next

a = brep_list

The breps will be placed as if the block was inserted in the world origin.

Permalink Reply by Vicente Soler on September 4, 2009 at 4:40pm

Sorry, i misread your comment. You want to actually transform and add block instances, not just read it's geometry. Then i think you'll have to do everything inside a vb.net component. Try going through this code for that:
http://en.wiki.mcneel.com/default.aspx/McNeel/CCommandTestInsert

Permalink Reply by Jacek Jaskólski on September 7, 2009 at 1:58am

I feared you would redirect me to that page :)
It's a bit too complicated for me. At least for now.

Many thanks though!
And for the VB code for extracting breps from blocks - very useful.

Permalink Reply by Firat Aydin on June 16, 2014 at 1:41am

can you help me tor write that in VB
mine is giving compile error

Permalink Reply by David Rutten on September 4, 2009 at 5:03pm

Hi JJ,

it is possible to do this through a VB Script component. But blocks are not supported by any Grasshopper components.

The implementation of blocks in the Rhino SDK is pretty disgusting. I've only dabbled with it once or twice but it's really convoluted.

Permalink Reply by Jacek Jaskólski on September 7, 2009 at 2:03am

It's good to know that - another reason to leave it for the moment.

Thanks for the reply!

Permalink Reply by Arthur Mamou-Mani on January 10, 2011 at 7:18am

Hi Jacek,

Have you ever managed to solve this question ?

Is there a Rhinoscript method for "export block" ?

Cheers,

Arthur

Permalink Reply by Jacek Jaskólski on January 10, 2011 at 2:53pm

Hi Arthur,

1. No, I haven't... It came out to be too difficult for me at that time. And it probably still is, depending on the "power of the comparison algorithm" as Hanno suggested.

2. What do you mean "export block"?

Permalink Reply by Alan on December 15, 2016 at 11:45am

Gents,

Almost 6 years after the last comment on this post. Have somebody managed to look into this solution yet?

Many thanks!

Alan

Permalink Reply by Bum Bumaye on December 16, 2016 at 1:21am

hey alan,

you can try the plugin Elefront . they added new components to the plugin to reference and bake blocks. you can even use native components to transform the blocks and then bake it as a block.

pretty nice,

greets