I have two 3D objects in my Sketchup file, which I would like to merge into one. Here’s a simple example of what I’m trying to do - if you can explain how, I can apply the process to my more complicated shapes:

- Imagine I have a cube, defined by 8 vertices (P1-P8). P1-P4 are on the X-Y (flat) plane, P5-P8 are directly above P1-P4 - also in an X-Y plane, but displaced vertically in the Z plane, making a cube.
- Imagine I have a second cube, with the same dimensions as the first cube, defined by vertices P9-P16. This cube is offset somewhere in the file - in X, Y, and Z directions. P9-12 are the vertices directly below P13-P16.
- I would like to merge the cubes, so that they form a rectangular prism, by essentially sitting one cube on top of the other (so the prism’s height is twice its length or width). I would like this prism to be one object, not just two objects that happen to be on top of one another.
- Essentially, P5 and P9 become the same vertex, P6 and P10 become the same vertex, P7 and P11 become the same vertex, and P8 and P12 become the same vertex. In the end, I should only be left with P1-P8 and P13-P16 as vertices - that is, 12 total vertices, not 16.

How can I do this?

(Please note that my actual objects - more complicated than cubes - still have vertices that can be correlated between the two objects, as in the cube example, so I don’t have to worry about the complication of joining two arbitrary objects that weren’t designed to eventually be merged).

Thank you.