Move geometry by picking it and dragging by mouse

[pspeed]

The math is the same once you’ve got your picking.

The easiest way to get started might be to skim this section of the docs:

Modules

…and maybe look at this example:

Lemur Gems #3 : Scene picking

Lemur has a robust picking subsystem that uses JME’s standard ray collision code. In this Lemur Gem, I add simple mouse picking to the app already built in Lemur Gem #1 and Lemur Gem #2 When you initialize Lemur’s GuiGlobals, it automatically adds the MouseAppState that does scene picking. It also adds the guiNode and rootNode to the pickable scene roots automatically. This demo uses that automatic setup. It is also possible to use the MouseAppState without the rest of Lemur but for simplic…

To quickly get started with Lemur and get the dependencies hooked up and so on, you can check here:

Getting Started

…and just stop after this:
GuiGlobals.initialize(this);

That line is all you need to initialize the built-in picking support. The first link I gave you talks about manually setting it up but if you call GuiGlobals.initialize(app) then you don’t have to do that.

After that, you can add a mouse listener or cursor listener to any JME Spatial.

If you get to that point, we can talk about whether you want to add a listener to every draggable spatial or one listener to the parent that contains them.