I have the following model, a series of rectangles, with vertical edges extruded. The face, and the side extrusion exist as independant surfaces within grasshopper. I want to merge these into one surfaces, so other operations (offset, fillet etc) effect the entire surface, not the component surfaces in isolation. In other CAD systems, this would probably be a stitch operation, but it doesn’t seem to be the case in GH.
As an extension to this. My next step is to add a second extrusion to the side extrusions, such that the left side edge will extrude to the right, and the right side edge will extrude to the left.
Any suggestions on how to achieve this?
As far as I know, there’s no such function that I know of… If what you’re saying is “Poly-Surface”, ie “Brep” then you could do something like this. You’ll need Sasquatch plugin.
If you don’t want to use a plugin you can also use “Move” with a direction input from a “Evaluate Surface” component in place of @HS_Kim’s example Sasquatch node “Offset Brep”, then you will have the original face, the new offset face and can use “Loft” or “Ruled Surface” to create the sides by lofting from the original face border to the offset face border, then, finally use “Brep Join” to put it all together as one Polysurface.
Again, only if you don’t want to use plugins, otherwise the example that was shared should work well for your purposes and is obviously easier as a single node.
I’ll try and share a quick example later today. Not needed but just to share for an alternative method/native version
Ok, so first things first - The key thing I was missing, was that for components like ‘BREP Join’ you hold shift click to add multiple surfaces. I didn’t mention it to keep my original post short, but I’m new to grasshopper - this is my first project.
In any case, I tried both options, and neither seems to work the way I hoped. The BREP Join option allow the faces to be treated as one, but when you use Deconstruct BREP to extract the edges, I foudn that there are no common edges, instead, adjacent faces have overlapping edges with unique indices.
What I hoped to see was that adjacent faces shared a common edge (with a common edge index).
Given that I’m new, I’ll explain why. The reason I’m expecting this is because the fillet command requires that I provide edge indices for the edges to fillet. Presumably, this means that faces need to share a common edge, and therefore have a single index.
To test the methods, I’m also baking the final preview and manually selecting faces, and they’re still singular when I expected them to be polysurfaces.
