Is there a GH component to detect mouse down event?
No. Some components detect a mousedown themselves and handle it, and Kangaroo can respond to mousedown and mousemove in the Rhino viewports, but nothing exposes this information to other components.
Two updates:
- Found a component called: Mouse event that helped
- Found a component select preview that solved what I tried to build with the Mouse event component (select GH object in Rhino)