Moving coplanar components towards 3d surfaces


I try to model a solar plant on a particular location.
Here is my situation :

  • i have a first layer with many ( >5000) identical components (solar panel structures), placed on an horizontal plane. Their position has been set before. (I designed it according to a 2D map of the site)
  • I have a layer with the topographic lines of the site where I want to place the plant. These lines are in 3D. I created surfaces from it thanks to the tools “From Contours” in Sandbox.

I would like to move each of my components to fit the topographic surfaces. It is easy for one particular component : I select a bottom corner, I force a vertical (blue) move and put my cursor to the corresponding surface. If I want to make it perfect, I need to rotate it to fit the angle of the surface.

So it is easy for one component but I have thousands of them.

My question is : is there a way to make it automatic ? I would select all my components, then select the “Magic*” tool, select the layer with the surfaces, and that would be done.

Thank you very much for your help !

Try the following extension: Drop GC


Hello Gully,

It looks promising ! I try it and give you a feedback ASAP.

Thank you very much for your quick answer !


So I installed and tried the plugin Drop GC.

Globally it works fine. Thank you !!

Two issues still.

1- When I select all of my components, and execute the DropGC command (see picture below) :

  • some of the components move (GREEN)
  • some components do not move (RED)
  • some components move at a random altitude betweem the moved ones and the others that did not move (BLACK)

If i click several times, it gets better : more components move.

Any idea on the reason / how I can solve this problem ?

2- As you almost immediatly solved my component dropping problem, I challenge you again : do you know if from these components touching my surface, I can rotate them so that they perfectly fit the surface ?

A big thank you for your quick and efficient answer!


Sorry, I just happened to remember there was an extension like that. I don’t really use it myself, so I can’t answer your questions, although perhaps someone who does and can will happen by.


Edit: Hey, wait a minute. If that’s a solar array, don’t you have to aim all the elements rather than just let them follow the random ground surface?

It would be practical to provide a base assembly to house a specific number of the solar panels in a group, rather than to align each unit to the change in slope. This assembly could be compared to a structural foundation (the material for such an assembly would likely be metal rather than formed poured-in-place concrete.) There could be a myriad of such groups placed on your site and as @Gully_Foyle correctly indicated, each solar panel should be oriented to face the sun and not so much be affected by the site contours. In fact, the most effective panel configurations are designed to follow the movement of the sun. If this setup is used then you only need concern yourself with the support points as they come into contact with the ground.

Aha. Notwithstanding my objections and those of @jvleearchitects, here’s a drop plugin that drops objects flat against the ground like the Tower of Pisa.

You need to register (free) at SketchUcation.



Hey guys,

Thank you very much for your answers.

First, thank you Gully for the Smartdrop plugin that does exactly what I wanted, and better than DropGC. It’s perfect.

Second, regarding your remarks about a solar plant layout, I totally agree with you in the general case. In my situation, I have fixed, ground-mounted solar panels. The topography is not a big concern (only small slope) so the best compromise between efficiency and economy is to orient all tables with the same angle, and fixe them into the ground, without any concern about the fact that for some, the orientation is not perfect due to the ground inclinaison. Indeed, providing foundation; or adjust each panel would cost too much regarding the relative gain in efficiency (less than a percent).
That’s why I just wanted to drop all my tables onto the ground, to have a 3D modeling of my future plant.

So, thank you very much for your quick answers, and more than that, your accuracy !

Best regards,