Get Block Transformation info in GH?

[lmnoc1]

Hi I am trying to access the transformation matrix from blocks in Grasshopper. (Many blocks in the scene. Some block rotations are not at 30 degree increment so I want to fix that in GH)

I imported blocks instances into GH with Elefront plugin (it doesnt has trans matrix info function). I am planning to get the matrix in c#, round the XY rotation to 30 degree, and create the new instances with correct transformation. I was reading this post

Block Transform Info

The info you’re looking at is, I think, a 4x4 transformation matrix (look at the characteristic 0,0,0,1 on the last line). This bit of code give you access to the instance transformation matrix. ObjRef p1; RhinoGet.GetOneObject("Select block", false, ObjectType.AnyObject, out p1); var obj = p1.Object(); InstanceObject io = obj as InstanceObject; if (null != io) { Transform t = io.InstanceXform; RhinoApp.WriteLine(t.ToString()); } return Result.Success;

Menno’s Rhino macro uses InstanceObject.InstanceXform
How can I get that in GH C#? Thanks

[elevelle (Evan Levelle)]

Hi @lmnoc1

If you are using R7, the new version of eleFront has a block info component that should give you the transformation.

Let me know if something is off.

[PeterFotiadis (Pfotiad0)]

@lmnoc1

C#?

For Instance References do something like this:

[AndyPayne]

If you’re using Rhino 8, you can use some of the new Block components to get the transforms for each instance. Something like this.

BlockTransforms.gh (8.3 KB)

[lmnoc1]

Thanks. I thought I just download it. But looks like it got an upgrade yesterday. Did you upload it just for me? Looks great!

Edit: The Block Container (for referencing instances) seems to be missing in beta, no reaction after right click Set Multiple Blocks. You should make it a standalone component. I can’t find it so I normally extract parameter to get it in 4.2.2. Also the 4.2.2 version Deconstruct Block has a plane output which is quite nice