Geo Nodes - Raycast from individual Mesh islands

Question

I try to create a Node Setup with which I can make several unconnected Planes (contained in one Object) snap to an underlying Groundplane without the Planes beeing rotated (Pic01).

With my current Setup I can only make the Planes snap to the Groundplane completely, like with a Shrinkwrap Modifier (Pic02).

Maybe there´s a way to separate each Island, kind of give them individual Origins from which the Raycast shoots down and then I snap the Plane to this Position?

Thanks for helping!

Answer 1

To achieve this goal, you would actually only have to use the node Raycast in relation to the domain Face, instead of the domain Point.

Since Set Position modifies the individual points of a geometry, working in the attribute domain Point, you simply capture the values with Capture Attribute in the domain Face and then transfer these values.

Like this:

Here is another alternative that uses an offset instead of resetting the position:

_{(Blender 3.2+)}